Watershed modelling tools like ArcSWAT, an ArcGIS extension of Soil and Water Assessment tool (SWAT), are useful to watershed managers in many ways. One particular use is analyzing model outputs for decision making re...Watershed modelling tools like ArcSWAT, an ArcGIS extension of Soil and Water Assessment tool (SWAT), are useful to watershed managers in many ways. One particular use is analyzing model outputs for decision making related to waterway restoration and mitigation, which is often undertaken to improve water quality in streams. The present study evaluates the use of digital elevation model (DEM) at 10 meter, 30 meter, and 100 meter pixel size on non-point runoff predictions for three sub-watersheds in Raritan River Basin in New Jersey. These three watersheds include: Bound Brook, Lamington River, and Lawrence Brook watersheds. ArcSWAT is utilized to investigate the difference due to DEM variation in predicting monthly estimates of pollutant loads including ammonium (NH4), nitrite (NO2) and sediment transported with water out of a watershed. Using land use/cover, slope and soil data for 2012, monthly pollutant loads are calculated for each sub-basin in the watershed over a 10-year simulation period (2012-2022) in ArcSWAT. Overall statistical and spatial results show that ArcSWAT results are sensitive to changes in DEM pixel size for watershed modeling. The results show that total sum of monthly runoffs including NH4, NO2 and sediment differ among the three different DEMs. Moreover, the spatial pattern of input (in sub-catchments) also changes among the three DEMs for most watersheds. This indicates that watershed managers need to supplement model predictions with field measurements before making substantial investments in stream restoration programs.展开更多
Road runoffs were sampled from five highways and five urban roads located in the New Juaben Municipality during the late storm events in the month of November 2014 and the early storm events in January 2015. A variety...Road runoffs were sampled from five highways and five urban roads located in the New Juaben Municipality during the late storm events in the month of November 2014 and the early storm events in January 2015. A variety of water quality parameters such as, pH, temperature, turbidity, electrical conductivity (EC), total suspended solids (TSS), total dissolved solids (TDS), aqueous concentrations of Chloride (Cl<sup>-</sup>), Phosphate (), Nitrate () and Sulphate () ions as well as the total concentrations of some selected heavy metals (Fe, Cu, Zn, Pb, Cd, Ni and Cr) were analysed for both periods. Although the results for the studied parameters, particularly the heavy metals varied for both sampling periods, the general trend indicated an increase in accumulation from November 2014 to January 2015. This was attributed to vehicular deposition as well as other natural and anthropogenic depositions on the road surfaces during the antecedent dry weather period between the two sampling months. The highest increase in pollutant loadings was associated with the heavy metals and some physico-chemical parameters such as TSS, TDS, EC and turbidity. Generally, EC, TDS, TSS and turbidity were above the permissible limits of the Environmental Protection Agency (EPA) of Ghana for both sampling periods. However, almost all the mean concentrations of heavy metals recorded for both road runoffs and the control samples were within the permissible limits of the Ghana EPA with some few exceptions.展开更多
Based on monthly runoff and climate datasets spanning 2000–2024,this study employed the Theil–Sen’s slope estimation,Mann–Kendall(M–K)trend test,as well as Pearson correlation and Spearman rank correlation analys...Based on monthly runoff and climate datasets spanning 2000–2024,this study employed the Theil–Sen’s slope estimation,Mann–Kendall(M–K)trend test,as well as Pearson correlation and Spearman rank correlation analyses to systematically examine the spatiotemporal patterns of runoff and its climatic driving mechanisms across Tajikistan,providing a scientific basis for sustainable water resource utilization and management in the study area.Results indicated that during 2000–2024,the annual runoff in Tajikistan exhibited statistically non-significant long-term trend(P=0.76),while displaying pronounced seasonal variability and strong spatial heterogeneity.Spring and summer average runoff primarily exhibited slight declining tendencies,while winter average runoff exhibited pronounced reduction in localized regions,such as the Syr Darya Basin,the Vakhsh River Basin,and the lower reaches of the Zeravshan River Basin.Precipitation emerged as the dominant positive driver of runoff,exhibiting moderate to strong positive correlations across over 78.00%of the country,whereas potential evapotranspiration consistently functioned as a negative driver.Rising temperatures exerted a dual competitive effect on runoff:in high-elevation,glacier-covered regions,rising temperatures temporarily increased runoff by accelerating glacier melt;however,at the national scale,the negative impact of rising temperature on runoff has played a slightly dominant role to a certain extent by enhancing evapotranspiration.Collectively,these results indicated that the present stability of runoff in Tajikistan is strongly dependent on the short-term compensatory effects of glacier melt and the risk of future runoff decline is likely to intensify as glacier reserves continue to diminish.This study provides a critical scientific evidence to inform sustainable water resource management in Tajikistan and underscores the need for glacier conservation and integrated water resource management strategies.展开更多
Climatic change has significant impacts on snow cover in mid-latitude mountainous re- gions, in the meantime, spatial and temporal changes of snow cover and snowmelt runoffs are con- sidered as sensitive indicators fo...Climatic change has significant impacts on snow cover in mid-latitude mountainous re- gions, in the meantime, spatial and temporal changes of snow cover and snowmelt runoffs are con- sidered as sensitive indicators for climatic change. In this study, the upper Heihe Watershed in the Qilian Mountains was selected as a typical area affected by snow cover and snowmelt runoffs in northwestern China. The changes in air temperatures, precipitation, snowfall and spring snowmelt runoffs were analyzed for the period from 1956 to 2001. The results indicate that climatic warming was apparent, particularly in January and February, but precipitation just fluctuated without a clear trend. The possible changes of snowmelt runoffs in the upper Heihe watershed in response to a warming of 4℃ were simulated using Snowmelt Runoff Model (SRM) based on the degree-day factor algorithm. The results of the simulation indicate that a forward shifting of snow melting season, an increase in water flows in earlier melting season, and a decline in flows in later melting season would occur under a 4℃ warming scenario.展开更多
The water and dissolved pollutant runoffs on impervious surfaces are the essential factor to be considered in design methods to minimize the impacts of the diffuse water pollution. In this paper, experiments are condu...The water and dissolved pollutant runoffs on impervious surfaces are the essential factor to be considered in design methods to minimize the impacts of the diffuse water pollution. In this paper, experiments are conducted to study the water and dissolved pollutant runoffs on impervious surfaces for different rainfall intensities and surface roughnesses. It is shown that a larger rainfall intensity and a smaller surface roughness reduce the time of concentration and increase the pollutant transport rate. Most of the pollutant runoffs take place at the initial stage of the rainfall. The pollutant transport rate rapidly reaches a peak and then gradually drops to zero.展开更多
Emerging contaminants(ECs)have raised global concern due to their adverse effect on ecosystems and human health.However,the occurrence and transport of ECs in stormwater remain unclear.The impact of ECs from stormwate...Emerging contaminants(ECs)have raised global concern due to their adverse effect on ecosystems and human health.However,the occurrence and transport of ECs in stormwater remain unclear.The impact of ECs from stormwater on surface water quality and ecosystem health is also poorly documented.In this review,we examined the variations in EC concentrations in surface water resulting from stormwater.During the wet weather,the concentrations of most investigated ECs,e.g.,microplastics,per-and polyfluoroalkyl substances,and vehicle-related compounds,significantly increase in surface water,indicating that stormwater may be a critical source of these contaminants.Furthermore,the potential pathways of ECs from stormwater enter surface water are outlined.Studies demonstrate that surface runoff and combined sewer overflows are important pathways for ECs,with discharges comparable to or exceeding those from wastewater treatment plants.Illicit connection also plays an important part in elevated EC concentrations in surface water.Overall,our findings underscore the importance of stormwater as a source for ECs in surface waters,and urge for increased emphasis on,and reinforcement of,stormwater monitoring and control measures to minimize the transport of ECs into receiving water bodies.展开更多
[Objective]Under the combined impact of climate change and urbanization,urban rainstorm flood disasters occur frequently,seriously restricting urban safety and sustainable development.Relying on traditional grey infra...[Objective]Under the combined impact of climate change and urbanization,urban rainstorm flood disasters occur frequently,seriously restricting urban safety and sustainable development.Relying on traditional grey infrastructure such as pipe networks for urban stormwater management is not enough to deal with urban rainstorm flood disasters under extreme rainfall events.The integration of green,grey and blue systems(GGB-integrated system)is gradually gaining recognition in the field of global flood prevention.It is necessary to further clarify the connotation,technical and engineering implementation strategies of the GGB-integrated system,to provide support for the resilient city construction.[Methods]Through literature retrieval and analysis,the relevant research and progress related to the layout optimization and joint scheduling optimization of the GGBintegrated system were systematically reviewed.In response to existing limitations and future engineering application requirements,key supporting technologies including the utilization of overground emergency storage spaces,safety protection of underground important infrastructure and multi-departmental collaboration,were proposed.A layout optimization framework and a joint scheduling framework for the GGB-integrated system were also developed.[Results]Current research on layout optimization predominantly focuses on the integration of green system and grey system,with relatively fewer studies incorporating blue system infrastructure into the optimization process.Moreover,these studies tend to be on a smaller scale with simpler scenarios,which do not fully capture the complexity of real-world systems.Additionally,optimization objective tend to prioritize environmental and economic goals,while social and ecological factors are less frequently considered.Current research on joint scheduling optimization is often limited to small-scale plots,with insufficient attention paid to the entire system.There is a deficiency in method for real-time,automated determination of optimal control strategies for combinations of multiple system facilities based on actual rainfall-runoff processes.Additionally,the application of emergency facilities during extreme conditions is not sufficiently addressed.Furthermore,both layout optimization and joint scheduling optimization lack consideration of the mute feed effect of flood and waterlogging in urban,watershed and regional scales.[Conclusion]Future research needs to improve the theoretical framework for layout optimization and joint scheduling optimization of GGB-integrated system.Through the comprehensive application of the Internet of things,artificial intelligence,coupling model development,multi-scale analysis,multi-scenario simulation,and the establishment of multi-departmental collaboration mechanisms,it can enhance the flood resilience of urban areas in response to rainfall events of varying intensities,particularly extreme rainfall events.展开更多
Previous works were mainly concentrated on long-term average runoff alterations,and extreme temperatures and watershed conditions are little analyzed.In this study,we collected gauged river flow and meteorological dat...Previous works were mainly concentrated on long-term average runoff alterations,and extreme temperatures and watershed conditions are little analyzed.In this study,we collected gauged river flow and meteorological data time series from 1916 to 2015 and 1941 to 2015 across the contiguous United States(CONUS)for 188 catchments to investigate the temporal trends and spatial features of runoff changes at multi-time scales.We also analyzed the relationships between runoff changes and climatic factors.Median descriptive statistics and Budyko coupled climate elasticity methods were used to calculate runoff elasticity in each time scale.The original Mann-Kendall trend test was used to test their trend significance in four time-scale(11,20,40,and 60 a),respectively.The results show that the trend of runoff changes is more significant in high time scales;total changes are heterogeneous over CONUS.After the 1970s,increases of up to 27%decade-1 were mainly concentrated in the mid-northern regions.Maximum temperature and catchment characteristics are vital factors for runoff alteration;runoff changes are independent of rainfall,and wet regions tend to have lower changes.These findings could help develop better regional water resource planning and management.展开更多
Microplastics(MPs),as a new category of environmental pollutant,have been the hotspot of eco-friendly issues nowadays.Studies based on the aging process,the migration pattern of MPs in runoff rainwater,and the use of ...Microplastics(MPs),as a new category of environmental pollutant,have been the hotspot of eco-friendly issues nowadays.Studies based on the aging process,the migration pattern of MPs in runoff rainwater,and the use of bioretention cells to remove MPs from runoff rainwater are beginning to attract widespread attention.This review analyses the migration patterns of MPs in rainwater runoff through their sources,structure and characteristics.The mechanism of removing MPs from runoff stormwater,the purification efficiency of different fillers and their influencing factors,and the accumulation,fate,and aging of MPs in bioretention cells are described.Furthermore,the hazards of MP accumulation on the performance of bioretention cells are summarised.Future directions for removing MPs in bioretention cells are proposed:(1)research on MPs smaller than 100μm;(2)influence of MPs aging process on bioretention cells;(3)exploration of more effective fillers to enhance their removal efficiency;(4)research on synergistic removal mechanism of MPs and other pollution.展开更多
Land use and precipitation are two major factors affecting phosphorus(P)pollution of watershed runoff.However,molecular characterization of dissolved organic phosphorus(DOP)in runoff under the joint influences of land...Land use and precipitation are two major factors affecting phosphorus(P)pollution of watershed runoff.However,molecular characterization of dissolved organic phosphorus(DOP)in runoff under the joint influences of land use and precipitation remains limited.This study used Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR-MS)to study the molecular characteristics of DOP in a typical P-polluted watershed with spatially variable land use and precipitation.The results showed that low precipitation and intense human activity,including phosphate mining and associated industries,resulted in the accumulation of aliphatic DOP compounds in the upper reaches,characterized by low aromaticity and low biological stability.Higher precipitation and widespread agriculture in the middle and lower reaches resulted in highly unsaturated DOP compounds with high biological stability constituting a higher proportion,compared to in the upper reaches.While,under similar precipitation,more aliphatic DOP compounds characterized by lower aromaticity and higher saturation were enriched in the lower reaches due to more influence from urban runoff relative to the middle reaches.Photochemical and/or microbial processes did result in changes in the characteristics of DOP compounds during runoff processes due to the prevalence of low molecular weight and low O/C bioavailable aliphatic DOP molecules in the upper reaches,which were increasingly transformed into refractory compounds from the upper tomiddle reaches.The results of this study can increase the understanding of the joint impacts of land use and precipitation on DOP compounds in watershed runoff.展开更多
This study aims to construct a large-scale hydrological Variable Infiltration Capacity(VIC)model based on temperature and precipitation at high altitudes,while elucidating the applicability of the model for hydrologic...This study aims to construct a large-scale hydrological Variable Infiltration Capacity(VIC)model based on temperature and precipitation at high altitudes,while elucidating the applicability of the model for hydrological simulation and analyzing the factors affecting runoff volume.Runoff volume and runoff depth were simulated using the VIC model and its performance was evaluated.Meanwhile,the factors affecting runoff volume were analyzed using Spearman correlation.The following model sensitivity parameters were obtained based on the China Natural Runoff Grid Point Dataset(CNRD v1.0):The variable infiltration curve parameter was 0.3,the Dsmax fraction where non-linear baseflow begins was 0.02,the maximum baseflow velocity was 15 mm/d,the maximum soil moisture where non-linear baseflow occurred was 0.7,the second soil moisture layer thickness was 0.3,and the thickness of the third soil moisture layer was 1.5.The surface runoff values in the Nyang River basin were similar in the first and fourth quarters(1.05–2.27 mm and 2.38–4.77 mm,respectively),and the surface runoff values were similar in the second and third quarters when the surface runoff was greater(23.46–52.20 mm and 60.59–85.63 mm,respectively).Watershed area,temperature,and precipitation significantly influenced the amount of runoff from the Nyang River.The applicability of the model to the Nyang River basin was confirmed using two different rate models.In some areas,precipitation and temperature did not have a dominating influence on runoff.Although the VIC model has significant advantages in runoff simulation,it requires a wealth of meteorological,soil,and hydrological data that may be difficult to obtain in some areas.展开更多
As China’s second longest river,the Yellow River(YR)carries a large volume of fresh water into the Bohai Sea with abundant nutrients and,thus,plays a crucial role in regulating the temperature and salinity near the Y...As China’s second longest river,the Yellow River(YR)carries a large volume of fresh water into the Bohai Sea with abundant nutrients and,thus,plays a crucial role in regulating the temperature and salinity near the YR Delta.In this study,using the runoff data and the Finite Volume Community Ocean Model,we simulated the salinity distribution near the YR Estuary for 2013-2022.We investigated the effect of the YR runoff on salinity dispersion and established the relationship between salinity distribution and the river’s runoff volume.Additionally,we analyzed the relationship between fish eggs and salinity distribution using fish egg da-ta.Findings indicated that the freshwater discharged from the YR converged into Laizhou Bay under the influence of tide.The sever-al years of simulation results(2013-2022)showed that the salinity field near the YR Estuary changed with the variations of river runoff entering the sea.Simultaneously,we found a positive correlation between the area of low-salinity zones(below 27)and the monthly average river runoff,and this relation could be expressed as Y_(s)=0.7457X_(r)+78.904.The characteristics of fish egg distribution revealed that fish eggs were primarily distributed in the areas characterized by salinity in the range of 25-29.展开更多
Owing to glacial retreat and associated future runoff variations,major concerns have been raised over the sustainability of water resources in the Qilian Mountains.Based on the Python Glacier Evolution Model,we presen...Owing to glacial retreat and associated future runoff variations,major concerns have been raised over the sustainability of water resources in the Qilian Mountains.Based on the Python Glacier Evolution Model,we present projections of the Qiyi glacier for shared socioeconomic pathways(SSPs)calibrated with the glaciological mass balance.The results indicate the air temperature as the dominant factor in the continuous mass loss of the Qiyi Glacier in the future.Glacier area and volume are projected to decline to 0.16±0.11 km2(6.4%±4.4%,relative to 2015)and 0.0023±0.0006 km3(2.1%±1.5%,relative to 2015),respectively,by 2100,for SSP1-2.6.For SSP5-8.5,the glacier will disappear by 2088.The mass loss of the Qiyi Glacier will accelerate before 2050 for all SSPs but will decelerate after 2050 for SSP1-2.6 and SSP2-4.5.The peak water of glacier runoff will occur between2034 and 2045,with the duration of high water from 7 to 18 years.Thereafter,the runoff will rapidly decline till 2070–2080 and remain low afterward.Compared with the existing projections,the present projections indicate that the Qiyi Glacier will experience more drastic shrinkage and ice loss in the coming decades.Finally,the glacier runoff is expected to reach its peak water earlier with a shorter duration of high water.展开更多
This study employs the Long Short-Term Memory(LSTM)rainfall-runoff model to simulate and predict runoff in typical basins of the Jiziwan Region of the Yellow River,aiming to overcome the shortcomings of traditional hy...This study employs the Long Short-Term Memory(LSTM)rainfall-runoff model to simulate and predict runoff in typical basins of the Jiziwan Region of the Yellow River,aiming to overcome the shortcomings of traditional hydrological models in complex nonlinear environments.The Jiziwan Region of the Yellow River is affected by human activities such as urbanization,agricultural development,and water resource management,leading to increasingly complex hydrological processes.Traditional hydrological models struggle to effectively capture the relationship between rainfall and runoff.The LSTM rainfall-runoff model,using deep learning techniques,automatically extracts features from data,identifies complex patterns and long-term dependency in time series,and provides more accurate and reliable runoff predictions.The results demonstrate that the LSTM rainfall-runoff model adapts well to the complex hydrological characteristics of the Jiziwan Region,showing superior performance over traditional hydrological models,especially in addressing the changing trends under the influence of climate change and human activities.By analyzing the interannual and within-year variations of runoff under different climate change scenarios,the model can predict the evolution trends of runoff under future climate conditions,providing a scientific basis for water resource management and decision-making.The results indicate that under different climate change scenarios,the runoff in several typical basins of the Jiziwan Region exhibits different variation trends.Under SSP1-2.6 and SSP2-4.5,some basins,such as the Wuding River Basin,Tuwei River Basin,and Gushanchuan Basin,show a decreasing trend in annual runoff.For example,in the Wuding River Basin,the average runoff from 2025 to 2040 is 12.48 m^(3)/s(SSP1-2.6),with an annual decrease of 0.10 m^(3)/s;in the Tuwei River Basin,the runoff from 2025 to 2040 is 12.96 m^(3)/s(SSP1-2.6),with an annual decrease of 0.10 m^(3)/s.In contrast,under SSP3-7.0 and SSP5-8.5,with climate warming and changes in precipitation patterns,runoff in some basins shows an increasing trend,particularly during the snowmelt period and with increased summer precipitation,leading to a significant rise in runoff.展开更多
In this paper,different stands in Xianzhong Nursery of Pingjiang were selected as the research object to study the runoff generation and soil loss characteristics of different stands.The results showed that the annual...In this paper,different stands in Xianzhong Nursery of Pingjiang were selected as the research object to study the runoff generation and soil loss characteristics of different stands.The results showed that the annual surface runoff of each model in Pingjiang was between 50.50 and 70.38 mm,and the annual surface runoff of each stand decreased with years.There was no significant difference in the annual runoff between each stand,nor between each stand and its control.There were significant differences in soil erosion modulus among the models,and the number ranged from 139.20 to 197.79 t/(km^(2)·y).展开更多
This study investigated the impacts of spring runoff on the formation of halobenzoquinones(HBQs)and their correlation with common water quality parameters(WQPs)and aromatic amino acids(AAs)in source water.Source water...This study investigated the impacts of spring runoff on the formation of halobenzoquinones(HBQs)and their correlation with common water quality parameters(WQPs)and aromatic amino acids(AAs)in source water.Source water and treated water samples were collected at two drinking water treatment plants in 2021,2022,and 2023.HBQs and aromatic AAs were analyzed using solid phase extraction with high performance liquid chromatography–tandem mass spectrometry methods.The only HBQs detected in treated water were 2,6-dichloro-1,4-benzoquinone(DCBQ)and hydroxy–DCBQ(OH-DCBQ).The concentration of DCBQ was 3-4 times higher during spring runoff events than during non-spring-runoff periods,suggesting the impact of spring runoff on the formation of DCBQ.The DCBQ concentrations in finished water positively correlated with the color,dissolved organic carbon,total organic nitrogen,and specific ultraviolet absorbance WQPs of source water in 2021 and 2022.The temporal trend of the total aromatic AAs determined in source water was strongly and positively correlated to DCBQ in finished water.Finally,there was a significant positive correlation between the concentration of DCBQ determined immediately following the addition of chlorine and the presence of its transformation product,OH-DCBQ,in finished water.The results also showed that powdered activated carbon can remove some of the HBQ precursors in the sourcewater to reduce DCBQ formation.This study demonstrated that WQPs and aromatic AAs are useful indicators for the removal of precursors to reduce HBQ formation during drinking water treatment.展开更多
In this paper,different stands in Dongjiang Lake Reservoir area of Zixing were selected as the research objects,and the runoff generation and soil loss characteristics of different stands were studied.The results show...In this paper,different stands in Dongjiang Lake Reservoir area of Zixing were selected as the research objects,and the runoff generation and soil loss characteristics of different stands were studied.The results showed that the annual surface runoff of each model in Zixing was between 43.24 and 50.99 mm,and there was no significant difference in the annual runoff between each stand and its control.There were significant differences in soil erosion modulus among the models,and the number ranged from 127.37 to 165.58 t/(km 2·y).展开更多
The South-to-North Water Diversion Project in China aims to address the imbalanced distribution of water resources between the northern and southern regions,a critical safeguard for sustainable socio-economic and ecol...The South-to-North Water Diversion Project in China aims to address the imbalanced distribution of water resources between the northern and southern regions,a critical safeguard for sustainable socio-economic and ecological development.In this study,we investigated the hydroclimatic evolution of the water source area and its driving mechanisms using the inflow runoff data at Danjiangkou Reservoir from 1954 to 2013,along with multiple gridded hydroclimatic datasets.Based on the correlations between instrumental runoff data and gridded hydroclimatic variables,we used linear regression to extend the long-term runoff record to the period of 1902-2019.Our results indicate that climate changes,dominated by regional wet-dry cycles,have significant impacts on runoff variations,while the influence of human activities remains comparatively limited.Danjiangkou Reservoir can maintain a balanced base flow,even during the operation of the water diversion project.Preliminary synoptic climatology analyses reveal that runoff variations are mainly driven by the El Niño-Southern Oscillation(ENSO)and the Pacific Walker Circulation(PWC),which affect runoff by altering large-scale ocean-to-continent water vapor processes.This study advances the field by integrating multi-source data with analytical techniques,which enhances understanding of long-term runoff changes in the Danjiangkou Reservoir and their climatic drivers,ultimately supporting sustainable water resource management.展开更多
Climate change and human activities are primary drivers of runoff variations,significantly impacting the hydrological balance of river basins.In recent decades,the Yellow River Basin,China has experienced a marked dec...Climate change and human activities are primary drivers of runoff variations,significantly impacting the hydrological balance of river basins.In recent decades,the Yellow River Basin,China has experienced a marked decline in runoff,posing challenges to the sustainable development of regional water resources and ecosystem stability.To enhance the understanding of runoff dynamics in the basin,we selected the Dahei River Basin,a representative tributary in the upper reaches of the Yellow River Basin as the study area.A comprehensive analysis of runoff trends and contributing factors was conducted using the data on hydrology,meteorology,and water resource development and utilization.Abrupt change years of runoff series in the Dahei River Basin was identified by the Mann-Kendall and Pettitt tests:1999 at Dianshang,Qixiaying,and Meidai hydrological stations and 1995 at Sanliang hydrological station.Through hydrological simulations based on the Variable Infiltration Capacity(VIC)model,we quantified the factors driving runoff evolution in the Dahei River Basin,with climate change contributing 9.92%–22.91%and human activities contributing 77.09%–90.08%.The Budyko hypothesis method provided similar results,with climate change contributing 13.06%–20.89%and human activities contributing 79.11%–86.94%.Both methods indicated that human activities,particularly water consumption,were dominant factors in the runoff variations of the Dahei River Basin.The integration of hydrological modeling with attribution analysis offers valuable insights into runoff evolution,facilitating adaptive strategies to mitigate water scarcity in arid and semi-arid areas.展开更多
The Songhua River Basin(SRB),ranking third largest in China in terms of both runoff volume and basin area,has experi-enced frequent disasters and drastic changes in runoff since the early 20th century.Many studies hav...The Songhua River Basin(SRB),ranking third largest in China in terms of both runoff volume and basin area,has experi-enced frequent disasters and drastic changes in runoff since the early 20th century.Many studies have analyzed the causes of runoff re-duction;however,the spatiotemporal differences in runoff contributions and their underlying mechanisms remain poorly understood,which are crucial for regional water resources management and effective utilization.This study used the Mann-Kendall rank correlation trend test,continuous wavelet analysis,cumulative anomaly,and the slope change ratio of cumulative quantities(SCRCQ)method to explore the runoff changes characteristics and spatiotemporal differences of the contributions of climate change and human activities to runoff changes across three sub-basins of the SRB.The results show that:1)runoff from 1955 to 2022 in all the three sub-basins exhibit a statistically significant decreasing trend at 0.05 significant level.2)Four abrupt change points in runoff were detected in Nenjiang River Basin(NRB)and the mainstream of the SRB(MSRB),whereas only two change points in the Second Songhua River(SSRB).3)Runoff and precipitation series of the NRB and MSRB exhibit similar multi-timescale cycle characteristics with the most dominated cycles of 45-58 yr.In contrast,it is 12-18 yr for SSRB.4)Anthropogenic activities are the primary factor leading to in the reduction of runoff in NRB(74.33%-91.67%)and MSRB(50.11%-102.12%),whereas it is only 5.38%-33.12%in SSRB.This is attributed to the uneven distribution of regional climate and human activities in the entire SRB.5)With the growing demand for water diversion for agri-cultural irrigation,anthropogenic activities in the NRB and MSRB have increased.However,the opposite is found in SSR,where the in-creased influence of precipitation on runoff and water conservation policies are identified.展开更多
文摘Watershed modelling tools like ArcSWAT, an ArcGIS extension of Soil and Water Assessment tool (SWAT), are useful to watershed managers in many ways. One particular use is analyzing model outputs for decision making related to waterway restoration and mitigation, which is often undertaken to improve water quality in streams. The present study evaluates the use of digital elevation model (DEM) at 10 meter, 30 meter, and 100 meter pixel size on non-point runoff predictions for three sub-watersheds in Raritan River Basin in New Jersey. These three watersheds include: Bound Brook, Lamington River, and Lawrence Brook watersheds. ArcSWAT is utilized to investigate the difference due to DEM variation in predicting monthly estimates of pollutant loads including ammonium (NH4), nitrite (NO2) and sediment transported with water out of a watershed. Using land use/cover, slope and soil data for 2012, monthly pollutant loads are calculated for each sub-basin in the watershed over a 10-year simulation period (2012-2022) in ArcSWAT. Overall statistical and spatial results show that ArcSWAT results are sensitive to changes in DEM pixel size for watershed modeling. The results show that total sum of monthly runoffs including NH4, NO2 and sediment differ among the three different DEMs. Moreover, the spatial pattern of input (in sub-catchments) also changes among the three DEMs for most watersheds. This indicates that watershed managers need to supplement model predictions with field measurements before making substantial investments in stream restoration programs.
文摘Road runoffs were sampled from five highways and five urban roads located in the New Juaben Municipality during the late storm events in the month of November 2014 and the early storm events in January 2015. A variety of water quality parameters such as, pH, temperature, turbidity, electrical conductivity (EC), total suspended solids (TSS), total dissolved solids (TDS), aqueous concentrations of Chloride (Cl<sup>-</sup>), Phosphate (), Nitrate () and Sulphate () ions as well as the total concentrations of some selected heavy metals (Fe, Cu, Zn, Pb, Cd, Ni and Cr) were analysed for both periods. Although the results for the studied parameters, particularly the heavy metals varied for both sampling periods, the general trend indicated an increase in accumulation from November 2014 to January 2015. This was attributed to vehicular deposition as well as other natural and anthropogenic depositions on the road surfaces during the antecedent dry weather period between the two sampling months. The highest increase in pollutant loadings was associated with the heavy metals and some physico-chemical parameters such as TSS, TDS, EC and turbidity. Generally, EC, TDS, TSS and turbidity were above the permissible limits of the Environmental Protection Agency (EPA) of Ghana for both sampling periods. However, almost all the mean concentrations of heavy metals recorded for both road runoffs and the control samples were within the permissible limits of the Ghana EPA with some few exceptions.
基金funded by the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB0720203)the National Key Research and Development Program of China(2023YFF0805603).
文摘Based on monthly runoff and climate datasets spanning 2000–2024,this study employed the Theil–Sen’s slope estimation,Mann–Kendall(M–K)trend test,as well as Pearson correlation and Spearman rank correlation analyses to systematically examine the spatiotemporal patterns of runoff and its climatic driving mechanisms across Tajikistan,providing a scientific basis for sustainable water resource utilization and management in the study area.Results indicated that during 2000–2024,the annual runoff in Tajikistan exhibited statistically non-significant long-term trend(P=0.76),while displaying pronounced seasonal variability and strong spatial heterogeneity.Spring and summer average runoff primarily exhibited slight declining tendencies,while winter average runoff exhibited pronounced reduction in localized regions,such as the Syr Darya Basin,the Vakhsh River Basin,and the lower reaches of the Zeravshan River Basin.Precipitation emerged as the dominant positive driver of runoff,exhibiting moderate to strong positive correlations across over 78.00%of the country,whereas potential evapotranspiration consistently functioned as a negative driver.Rising temperatures exerted a dual competitive effect on runoff:in high-elevation,glacier-covered regions,rising temperatures temporarily increased runoff by accelerating glacier melt;however,at the national scale,the negative impact of rising temperature on runoff has played a slightly dominant role to a certain extent by enhancing evapotranspiration.Collectively,these results indicated that the present stability of runoff in Tajikistan is strongly dependent on the short-term compensatory effects of glacier melt and the risk of future runoff decline is likely to intensify as glacier reserves continue to diminish.This study provides a critical scientific evidence to inform sustainable water resource management in Tajikistan and underscores the need for glacier conservation and integrated water resource management strategies.
文摘Climatic change has significant impacts on snow cover in mid-latitude mountainous re- gions, in the meantime, spatial and temporal changes of snow cover and snowmelt runoffs are con- sidered as sensitive indicators for climatic change. In this study, the upper Heihe Watershed in the Qilian Mountains was selected as a typical area affected by snow cover and snowmelt runoffs in northwestern China. The changes in air temperatures, precipitation, snowfall and spring snowmelt runoffs were analyzed for the period from 1956 to 2001. The results indicate that climatic warming was apparent, particularly in January and February, but precipitation just fluctuated without a clear trend. The possible changes of snowmelt runoffs in the upper Heihe watershed in response to a warming of 4℃ were simulated using Snowmelt Runoff Model (SRM) based on the degree-day factor algorithm. The results of the simulation indicate that a forward shifting of snow melting season, an increase in water flows in earlier melting season, and a decline in flows in later melting season would occur under a 4℃ warming scenario.
基金supported by the National Natural Science Foun-dation of China(Grant No.51450110079)the Chinese Academy of Engineering(Grant No.2015-ZD-07-04-01)the Fundamental Research Funds for the Central Universities(Grant No.2015B41614)
文摘The water and dissolved pollutant runoffs on impervious surfaces are the essential factor to be considered in design methods to minimize the impacts of the diffuse water pollution. In this paper, experiments are conducted to study the water and dissolved pollutant runoffs on impervious surfaces for different rainfall intensities and surface roughnesses. It is shown that a larger rainfall intensity and a smaller surface roughness reduce the time of concentration and increase the pollutant transport rate. Most of the pollutant runoffs take place at the initial stage of the rainfall. The pollutant transport rate rapidly reaches a peak and then gradually drops to zero.
基金supported by the National Natural Science Foundation of China(Nos.52325001 and 52170009)the National Key Research and Development Program of China(No.2021YFC3200700)the Programof Shanghai Academic Research Leader,China(No.21XD1424000).
文摘Emerging contaminants(ECs)have raised global concern due to their adverse effect on ecosystems and human health.However,the occurrence and transport of ECs in stormwater remain unclear.The impact of ECs from stormwater on surface water quality and ecosystem health is also poorly documented.In this review,we examined the variations in EC concentrations in surface water resulting from stormwater.During the wet weather,the concentrations of most investigated ECs,e.g.,microplastics,per-and polyfluoroalkyl substances,and vehicle-related compounds,significantly increase in surface water,indicating that stormwater may be a critical source of these contaminants.Furthermore,the potential pathways of ECs from stormwater enter surface water are outlined.Studies demonstrate that surface runoff and combined sewer overflows are important pathways for ECs,with discharges comparable to or exceeding those from wastewater treatment plants.Illicit connection also plays an important part in elevated EC concentrations in surface water.Overall,our findings underscore the importance of stormwater as a source for ECs in surface waters,and urge for increased emphasis on,and reinforcement of,stormwater monitoring and control measures to minimize the transport of ECs into receiving water bodies.
文摘[Objective]Under the combined impact of climate change and urbanization,urban rainstorm flood disasters occur frequently,seriously restricting urban safety and sustainable development.Relying on traditional grey infrastructure such as pipe networks for urban stormwater management is not enough to deal with urban rainstorm flood disasters under extreme rainfall events.The integration of green,grey and blue systems(GGB-integrated system)is gradually gaining recognition in the field of global flood prevention.It is necessary to further clarify the connotation,technical and engineering implementation strategies of the GGB-integrated system,to provide support for the resilient city construction.[Methods]Through literature retrieval and analysis,the relevant research and progress related to the layout optimization and joint scheduling optimization of the GGBintegrated system were systematically reviewed.In response to existing limitations and future engineering application requirements,key supporting technologies including the utilization of overground emergency storage spaces,safety protection of underground important infrastructure and multi-departmental collaboration,were proposed.A layout optimization framework and a joint scheduling framework for the GGB-integrated system were also developed.[Results]Current research on layout optimization predominantly focuses on the integration of green system and grey system,with relatively fewer studies incorporating blue system infrastructure into the optimization process.Moreover,these studies tend to be on a smaller scale with simpler scenarios,which do not fully capture the complexity of real-world systems.Additionally,optimization objective tend to prioritize environmental and economic goals,while social and ecological factors are less frequently considered.Current research on joint scheduling optimization is often limited to small-scale plots,with insufficient attention paid to the entire system.There is a deficiency in method for real-time,automated determination of optimal control strategies for combinations of multiple system facilities based on actual rainfall-runoff processes.Additionally,the application of emergency facilities during extreme conditions is not sufficiently addressed.Furthermore,both layout optimization and joint scheduling optimization lack consideration of the mute feed effect of flood and waterlogging in urban,watershed and regional scales.[Conclusion]Future research needs to improve the theoretical framework for layout optimization and joint scheduling optimization of GGB-integrated system.Through the comprehensive application of the Internet of things,artificial intelligence,coupling model development,multi-scale analysis,multi-scenario simulation,and the establishment of multi-departmental collaboration mechanisms,it can enhance the flood resilience of urban areas in response to rainfall events of varying intensities,particularly extreme rainfall events.
基金supported by National Key R&D Program of China(No.2018YFC0407303)“Young Talents”Project of Northeast Agricultural University(No.20QC13)the Natural Science Foundation of Heilongjiang Province of China(No.E2017009)。
文摘Previous works were mainly concentrated on long-term average runoff alterations,and extreme temperatures and watershed conditions are little analyzed.In this study,we collected gauged river flow and meteorological data time series from 1916 to 2015 and 1941 to 2015 across the contiguous United States(CONUS)for 188 catchments to investigate the temporal trends and spatial features of runoff changes at multi-time scales.We also analyzed the relationships between runoff changes and climatic factors.Median descriptive statistics and Budyko coupled climate elasticity methods were used to calculate runoff elasticity in each time scale.The original Mann-Kendall trend test was used to test their trend significance in four time-scale(11,20,40,and 60 a),respectively.The results show that the trend of runoff changes is more significant in high time scales;total changes are heterogeneous over CONUS.After the 1970s,increases of up to 27%decade-1 were mainly concentrated in the mid-northern regions.Maximum temperature and catchment characteristics are vital factors for runoff alteration;runoff changes are independent of rainfall,and wet regions tend to have lower changes.These findings could help develop better regional water resource planning and management.
基金supported by the National Natural Science Foundation of China(No.52070152).
文摘Microplastics(MPs),as a new category of environmental pollutant,have been the hotspot of eco-friendly issues nowadays.Studies based on the aging process,the migration pattern of MPs in runoff rainwater,and the use of bioretention cells to remove MPs from runoff rainwater are beginning to attract widespread attention.This review analyses the migration patterns of MPs in rainwater runoff through their sources,structure and characteristics.The mechanism of removing MPs from runoff stormwater,the purification efficiency of different fillers and their influencing factors,and the accumulation,fate,and aging of MPs in bioretention cells are described.Furthermore,the hazards of MP accumulation on the performance of bioretention cells are summarised.Future directions for removing MPs in bioretention cells are proposed:(1)research on MPs smaller than 100μm;(2)influence of MPs aging process on bioretention cells;(3)exploration of more effective fillers to enhance their removal efficiency;(4)research on synergistic removal mechanism of MPs and other pollution.
基金supported by the Three Gorges Corporation (No.HBHB2023018)the Project of Hubei Provincial Key Research and Development (No.2022BCA074)the National Key Research and Development Program of China (No.2022YFC3705002).
文摘Land use and precipitation are two major factors affecting phosphorus(P)pollution of watershed runoff.However,molecular characterization of dissolved organic phosphorus(DOP)in runoff under the joint influences of land use and precipitation remains limited.This study used Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR-MS)to study the molecular characteristics of DOP in a typical P-polluted watershed with spatially variable land use and precipitation.The results showed that low precipitation and intense human activity,including phosphate mining and associated industries,resulted in the accumulation of aliphatic DOP compounds in the upper reaches,characterized by low aromaticity and low biological stability.Higher precipitation and widespread agriculture in the middle and lower reaches resulted in highly unsaturated DOP compounds with high biological stability constituting a higher proportion,compared to in the upper reaches.While,under similar precipitation,more aliphatic DOP compounds characterized by lower aromaticity and higher saturation were enriched in the lower reaches due to more influence from urban runoff relative to the middle reaches.Photochemical and/or microbial processes did result in changes in the characteristics of DOP compounds during runoff processes due to the prevalence of low molecular weight and low O/C bioavailable aliphatic DOP molecules in the upper reaches,which were increasingly transformed into refractory compounds from the upper tomiddle reaches.The results of this study can increase the understanding of the joint impacts of land use and precipitation on DOP compounds in watershed runoff.
基金supported by the Key R&D Project of Science and Technology Program of Tibet Autonomous Region(XZ202301ZY0006G)the Graduate High-level Talent Training Program of Xizang University(2022-GSP-B007)+1 种基金Nagqu City Science and Technology Program Key R&D Projects(NQKJ-2023-15)Central Financial Support for Local Universities to Construct Wetland Station in Mitika and Collaborative Innovation Center for Ecological Civilization of the Qinghai-Tibetan Plateau([2024]NO.01).
文摘This study aims to construct a large-scale hydrological Variable Infiltration Capacity(VIC)model based on temperature and precipitation at high altitudes,while elucidating the applicability of the model for hydrological simulation and analyzing the factors affecting runoff volume.Runoff volume and runoff depth were simulated using the VIC model and its performance was evaluated.Meanwhile,the factors affecting runoff volume were analyzed using Spearman correlation.The following model sensitivity parameters were obtained based on the China Natural Runoff Grid Point Dataset(CNRD v1.0):The variable infiltration curve parameter was 0.3,the Dsmax fraction where non-linear baseflow begins was 0.02,the maximum baseflow velocity was 15 mm/d,the maximum soil moisture where non-linear baseflow occurred was 0.7,the second soil moisture layer thickness was 0.3,and the thickness of the third soil moisture layer was 1.5.The surface runoff values in the Nyang River basin were similar in the first and fourth quarters(1.05–2.27 mm and 2.38–4.77 mm,respectively),and the surface runoff values were similar in the second and third quarters when the surface runoff was greater(23.46–52.20 mm and 60.59–85.63 mm,respectively).Watershed area,temperature,and precipitation significantly influenced the amount of runoff from the Nyang River.The applicability of the model to the Nyang River basin was confirmed using two different rate models.In some areas,precipitation and temperature did not have a dominating influence on runoff.Although the VIC model has significant advantages in runoff simulation,it requires a wealth of meteorological,soil,and hydrological data that may be difficult to obtain in some areas.
基金supported by the Yantai City Science and Technology Innovation Development Plan Project(Nos.2023JCYJ097 and 2023JCYJ094)the Key Project of the National Natural Science Foundation of China(No.42330406).
文摘As China’s second longest river,the Yellow River(YR)carries a large volume of fresh water into the Bohai Sea with abundant nutrients and,thus,plays a crucial role in regulating the temperature and salinity near the YR Delta.In this study,using the runoff data and the Finite Volume Community Ocean Model,we simulated the salinity distribution near the YR Estuary for 2013-2022.We investigated the effect of the YR runoff on salinity dispersion and established the relationship between salinity distribution and the river’s runoff volume.Additionally,we analyzed the relationship between fish eggs and salinity distribution using fish egg da-ta.Findings indicated that the freshwater discharged from the YR converged into Laizhou Bay under the influence of tide.The sever-al years of simulation results(2013-2022)showed that the salinity field near the YR Estuary changed with the variations of river runoff entering the sea.Simultaneously,we found a positive correlation between the area of low-salinity zones(below 27)and the monthly average river runoff,and this relation could be expressed as Y_(s)=0.7457X_(r)+78.904.The characteristics of fish egg distribution revealed that fish eggs were primarily distributed in the areas characterized by salinity in the range of 25-29.
基金supported by the National Natural Science Foundation of China(Nos.42130516,42171139,41871053)the Second Tibetan Plateau Scientific Expedition and Research Program(No.2019QZKK020102)+1 种基金Natural Science Basic Research Program of Shaanxi Province(No.2023–JC–QN–0300)the Science and Technology Program of Gansu Province(24JRRG012)。
文摘Owing to glacial retreat and associated future runoff variations,major concerns have been raised over the sustainability of water resources in the Qilian Mountains.Based on the Python Glacier Evolution Model,we present projections of the Qiyi glacier for shared socioeconomic pathways(SSPs)calibrated with the glaciological mass balance.The results indicate the air temperature as the dominant factor in the continuous mass loss of the Qiyi Glacier in the future.Glacier area and volume are projected to decline to 0.16±0.11 km2(6.4%±4.4%,relative to 2015)and 0.0023±0.0006 km3(2.1%±1.5%,relative to 2015),respectively,by 2100,for SSP1-2.6.For SSP5-8.5,the glacier will disappear by 2088.The mass loss of the Qiyi Glacier will accelerate before 2050 for all SSPs but will decelerate after 2050 for SSP1-2.6 and SSP2-4.5.The peak water of glacier runoff will occur between2034 and 2045,with the duration of high water from 7 to 18 years.Thereafter,the runoff will rapidly decline till 2070–2080 and remain low afterward.Compared with the existing projections,the present projections indicate that the Qiyi Glacier will experience more drastic shrinkage and ice loss in the coming decades.Finally,the glacier runoff is expected to reach its peak water earlier with a shorter duration of high water.
基金the National Key R&D Program of China(No.2023YFC3206504)National Natural Science Foundation of China(Nos.52121006,41961124006,51911540477)+1 种基金Young Top-Notch Talent Support Program of National High-level Talents Special Support PlanResearch Project of Ministry of Natural Resources(No.20210103)for providing financial support for this research。
文摘This study employs the Long Short-Term Memory(LSTM)rainfall-runoff model to simulate and predict runoff in typical basins of the Jiziwan Region of the Yellow River,aiming to overcome the shortcomings of traditional hydrological models in complex nonlinear environments.The Jiziwan Region of the Yellow River is affected by human activities such as urbanization,agricultural development,and water resource management,leading to increasingly complex hydrological processes.Traditional hydrological models struggle to effectively capture the relationship between rainfall and runoff.The LSTM rainfall-runoff model,using deep learning techniques,automatically extracts features from data,identifies complex patterns and long-term dependency in time series,and provides more accurate and reliable runoff predictions.The results demonstrate that the LSTM rainfall-runoff model adapts well to the complex hydrological characteristics of the Jiziwan Region,showing superior performance over traditional hydrological models,especially in addressing the changing trends under the influence of climate change and human activities.By analyzing the interannual and within-year variations of runoff under different climate change scenarios,the model can predict the evolution trends of runoff under future climate conditions,providing a scientific basis for water resource management and decision-making.The results indicate that under different climate change scenarios,the runoff in several typical basins of the Jiziwan Region exhibits different variation trends.Under SSP1-2.6 and SSP2-4.5,some basins,such as the Wuding River Basin,Tuwei River Basin,and Gushanchuan Basin,show a decreasing trend in annual runoff.For example,in the Wuding River Basin,the average runoff from 2025 to 2040 is 12.48 m^(3)/s(SSP1-2.6),with an annual decrease of 0.10 m^(3)/s;in the Tuwei River Basin,the runoff from 2025 to 2040 is 12.96 m^(3)/s(SSP1-2.6),with an annual decrease of 0.10 m^(3)/s.In contrast,under SSP3-7.0 and SSP5-8.5,with climate warming and changes in precipitation patterns,runoff in some basins shows an increasing trend,particularly during the snowmelt period and with increased summer precipitation,leading to a significant rise in runoff.
基金Supported by Hunan Forestry Science and Technology Plan(OT-S-KTA5,2024YBC15)Science and Technology Plan of Hunan Province(2021SFQ19).
文摘In this paper,different stands in Xianzhong Nursery of Pingjiang were selected as the research object to study the runoff generation and soil loss characteristics of different stands.The results showed that the annual surface runoff of each model in Pingjiang was between 50.50 and 70.38 mm,and the annual surface runoff of each stand decreased with years.There was no significant difference in the annual runoff between each stand,nor between each stand and its control.There were significant differences in soil erosion modulus among the models,and the number ranged from 139.20 to 197.79 t/(km^(2)·y).
基金supported by grants from the Natural Sciences and Engineering Research Council of Canada(NSERC)Alberta Innovates,and the Canada Research Chairs Program.The authors acknowledge the support of the NSERC Postgraduate Doctoral Scholarship(NJPW),the Alberta Innovates Graduate Student Scholarship(KC),and the 75th Anniversary Graduate Student Award and the Graduate Student Recruitment Scholarship of the Faculty of Medicine and Dentistry at the University of Alberta(KNMC).
文摘This study investigated the impacts of spring runoff on the formation of halobenzoquinones(HBQs)and their correlation with common water quality parameters(WQPs)and aromatic amino acids(AAs)in source water.Source water and treated water samples were collected at two drinking water treatment plants in 2021,2022,and 2023.HBQs and aromatic AAs were analyzed using solid phase extraction with high performance liquid chromatography–tandem mass spectrometry methods.The only HBQs detected in treated water were 2,6-dichloro-1,4-benzoquinone(DCBQ)and hydroxy–DCBQ(OH-DCBQ).The concentration of DCBQ was 3-4 times higher during spring runoff events than during non-spring-runoff periods,suggesting the impact of spring runoff on the formation of DCBQ.The DCBQ concentrations in finished water positively correlated with the color,dissolved organic carbon,total organic nitrogen,and specific ultraviolet absorbance WQPs of source water in 2021 and 2022.The temporal trend of the total aromatic AAs determined in source water was strongly and positively correlated to DCBQ in finished water.Finally,there was a significant positive correlation between the concentration of DCBQ determined immediately following the addition of chlorine and the presence of its transformation product,OH-DCBQ,in finished water.The results also showed that powdered activated carbon can remove some of the HBQ precursors in the sourcewater to reduce DCBQ formation.This study demonstrated that WQPs and aromatic AAs are useful indicators for the removal of precursors to reduce HBQ formation during drinking water treatment.
基金Supported by Science and Technology Plan of Hunan Province(2021SFQ19)Hunan Forestry Science and Technology Plan(OT-S-KTA5,2024YBC15).
文摘In this paper,different stands in Dongjiang Lake Reservoir area of Zixing were selected as the research objects,and the runoff generation and soil loss characteristics of different stands were studied.The results showed that the annual surface runoff of each model in Zixing was between 43.24 and 50.99 mm,and there was no significant difference in the annual runoff between each stand and its control.There were significant differences in soil erosion modulus among the models,and the number ranged from 127.37 to 165.58 t/(km 2·y).
基金supported by the National Natural Science Foundation of China(NSFC Project No.32061123008)the Innovation Training Programme for Undergraduate Students of Yunnan University(Project No.202301051).
文摘The South-to-North Water Diversion Project in China aims to address the imbalanced distribution of water resources between the northern and southern regions,a critical safeguard for sustainable socio-economic and ecological development.In this study,we investigated the hydroclimatic evolution of the water source area and its driving mechanisms using the inflow runoff data at Danjiangkou Reservoir from 1954 to 2013,along with multiple gridded hydroclimatic datasets.Based on the correlations between instrumental runoff data and gridded hydroclimatic variables,we used linear regression to extend the long-term runoff record to the period of 1902-2019.Our results indicate that climate changes,dominated by regional wet-dry cycles,have significant impacts on runoff variations,while the influence of human activities remains comparatively limited.Danjiangkou Reservoir can maintain a balanced base flow,even during the operation of the water diversion project.Preliminary synoptic climatology analyses reveal that runoff variations are mainly driven by the El Niño-Southern Oscillation(ENSO)and the Pacific Walker Circulation(PWC),which affect runoff by altering large-scale ocean-to-continent water vapor processes.This study advances the field by integrating multi-source data with analytical techniques,which enhances understanding of long-term runoff changes in the Danjiangkou Reservoir and their climatic drivers,ultimately supporting sustainable water resource management.
基金supported by the National Key Research and Development Program of China(2022YFC3204401)the National Natural Science Foundation of China(U23A2001,U2243234)+2 种基金the Major Science and Technology Projects of Inner Mongolia Autonomous Region(KCX2024013-1,2022EEDSKJXM005)the Inner Mongolia Autonomous Region Science and Technology Leading Talent Team(2022LJRC0007)the Inner Mongolia Agricultural University Basic Research Business Expenses Project(BR221012,BR221204).
文摘Climate change and human activities are primary drivers of runoff variations,significantly impacting the hydrological balance of river basins.In recent decades,the Yellow River Basin,China has experienced a marked decline in runoff,posing challenges to the sustainable development of regional water resources and ecosystem stability.To enhance the understanding of runoff dynamics in the basin,we selected the Dahei River Basin,a representative tributary in the upper reaches of the Yellow River Basin as the study area.A comprehensive analysis of runoff trends and contributing factors was conducted using the data on hydrology,meteorology,and water resource development and utilization.Abrupt change years of runoff series in the Dahei River Basin was identified by the Mann-Kendall and Pettitt tests:1999 at Dianshang,Qixiaying,and Meidai hydrological stations and 1995 at Sanliang hydrological station.Through hydrological simulations based on the Variable Infiltration Capacity(VIC)model,we quantified the factors driving runoff evolution in the Dahei River Basin,with climate change contributing 9.92%–22.91%and human activities contributing 77.09%–90.08%.The Budyko hypothesis method provided similar results,with climate change contributing 13.06%–20.89%and human activities contributing 79.11%–86.94%.Both methods indicated that human activities,particularly water consumption,were dominant factors in the runoff variations of the Dahei River Basin.The integration of hydrological modeling with attribution analysis offers valuable insights into runoff evolution,facilitating adaptive strategies to mitigate water scarcity in arid and semi-arid areas.
基金Under the auspices of National Natural Science Foundation of China(No.42271125)Jilin Province Foreign Expert Project(No.L202322)Doctoral Research Initiation Project of Jilin Normal University(No.0420237)。
文摘The Songhua River Basin(SRB),ranking third largest in China in terms of both runoff volume and basin area,has experi-enced frequent disasters and drastic changes in runoff since the early 20th century.Many studies have analyzed the causes of runoff re-duction;however,the spatiotemporal differences in runoff contributions and their underlying mechanisms remain poorly understood,which are crucial for regional water resources management and effective utilization.This study used the Mann-Kendall rank correlation trend test,continuous wavelet analysis,cumulative anomaly,and the slope change ratio of cumulative quantities(SCRCQ)method to explore the runoff changes characteristics and spatiotemporal differences of the contributions of climate change and human activities to runoff changes across three sub-basins of the SRB.The results show that:1)runoff from 1955 to 2022 in all the three sub-basins exhibit a statistically significant decreasing trend at 0.05 significant level.2)Four abrupt change points in runoff were detected in Nenjiang River Basin(NRB)and the mainstream of the SRB(MSRB),whereas only two change points in the Second Songhua River(SSRB).3)Runoff and precipitation series of the NRB and MSRB exhibit similar multi-timescale cycle characteristics with the most dominated cycles of 45-58 yr.In contrast,it is 12-18 yr for SSRB.4)Anthropogenic activities are the primary factor leading to in the reduction of runoff in NRB(74.33%-91.67%)and MSRB(50.11%-102.12%),whereas it is only 5.38%-33.12%in SSRB.This is attributed to the uneven distribution of regional climate and human activities in the entire SRB.5)With the growing demand for water diversion for agri-cultural irrigation,anthropogenic activities in the NRB and MSRB have increased.However,the opposite is found in SSR,where the in-creased influence of precipitation on runoff and water conservation policies are identified.
