Water quantity-quality combined evaluation method for rivers＇ water requirements of the instream environment in dualistic water cycle： A case study of Liaohe River Basin

In this article the meaning of the quantity and quality of environmental flows of river in dualistic water cycle is discussed, and compared with the meaning of unitary water cycle. Based on the analysis of the relationship between environmental flows of river requirements, the efficiency of water resource usage, the consumption coefficient, and the concentration of waste water elimination, the water quantity and water quality calculation method of the environmental flows of river requirements in dualistic water cycle is developed, and the criteria for environmental flows of river requirements are established, and therefore the water quantity-quality combined evaluation of natural river flows requirements are realized Taking the Liaohe River as a model, the environmental flows of river requirements for Xiliao River, Dongliao River, mainstream Liaohe River, Huntai River and northeast rivers along the coasts of the Yellow and Bohai seas in unitary water cycle are calculated, each taking up 39.3%, 63.0%, 43.9%, 43.3% and 43.5% of runoff respectively. Evaluated according to Tennant recommended flow, the results show that： except Xiliao River is ＂median＂, the rest are all upon ＂good＂, the Dongliao River is even ＂very good＂. The corresponding results in dualistic water cycle are that, the proportion of natural flows for each river is 57.5%, 74.1%, 60.8%, 60.3% and 60.4%; while the combined evaluation results show that： considering ＂quantity＂, except Xiliao River, the rest rivers can all achieve the ＂quantity＂ criteria of the en- vironmental flows of river requirements, but if considering the aspect of ＂quality＂, only Dongliao River can reach the ＂quality＂ standard. By water quantity-quality combined evaluation method, only Dongliao River can achieve the criteria. So the water quality is the main factor that determines whether the environmental flows can meet the river ecosystem demands.

Seepage effects of groundwater and its make-up water on triggering ground subsidence

The functioning mechanism of groundwater and its make-up water in the process of ground subsidence was studied from such three aspects as osmotic corrasion, osmotic pressure effect and concretion effect, As to osmotic corrasion, its forming conditions, mechanical mechanism and process were analyzed, As to osmotic pressure effect, it was mainly studied from hydrostatic pressurizing effect, sop softening effect and negative pressure sealing effect. Through concretion and saturation of soil, the factors of concretion settlement were analyzed. The results showed that both groundwater and its make-up water are important triggering factors to ground subsidence.

Study on resource quantity of surface water based on phase space reconstruction and neural network

Proposed a new method to disclose the complicated non-linearity structure of the water-resource system, introducing chaos theory into the hydrology and water resources field, and combined with the chaos theory and artificial neural networks. Training data construction and networks structure were determined by the phase space reconstruction, and establishing nonlinear relationship of phase points with neural networks, the forecasting model of the resource quantity of the surface water was brought forward. The keystone of the way and the detailed arithmetic of the network training were given. The example shows that the model has highly forecasting precision.

Impacts of climate change on water quantity, water salinity, food security, and socioeconomy in Egypt

Climate change might have direct impacts on water quantity in Egypt and lead to indirect effects on Mediterranean saltwater intrusion to groundwater,which exposes agriculture to vulnerability.This study investigated impacts of climate change on agriculture,with particular regard to food security and socioeconomy,and quantified the effectiveness of cropping pattern adaptation measures by integrating three mathematical models.The BlueM model was used for hydrological simulations of Nasser Lake under flooding scenarios to predict the water supply from the High Aswan Dam.The water and salinity balance(WB-SAL)model was adopted to estimate the water salinity in the Nile Delta.The simulated results from the BlueM and WB-SAL models were integrated with the agricultural simulation model for Egypt(ASME)to project cropping patterns,food security,and socioeconomy throughout the country.The results showed that future climate change will directly affect the total crop area;crop areas for 13 crop types;the self-sufficiency of wheat,rice,cereal,and maize supplies;and socioeconomic indicators.The proposed cropping pattern adaptation measures focus on fixing the crop areas of rice and orchards and providing half of the population with lentils,maize,onion,vegetables,milk,and meat.The adaptation measures have the potential to promote food security without causing deterioration of the socioeconomic situation.However,water availability has much more significant effects on food security and socioeconomy than cropping pattern adaptation measures do.Accordingly,the country should rationalize water use efficiency and increase water supply.©2021 Hohai University.Production and hosting by Elsevier B.V.This is an open access article under the CC BY-NC-ND license(http://creativecommons.org/licenses/by-nc-nd/4.0/).

Simulation of water quantity exchange between groundwater and the Platte River water, central Nebraska

The authors demonstrate the importance of the simulation of the water quantity exchange between river water and groundwater to a better understanding of the hydrologic relations between a river and nearby aquifer where groundwater is pumped extensively but only seasonally. And MODFLOW is used to design the stream aquifer model in which the pumpage of more than 1000 wells was simulated. The river gaining and river losing processes were analyzed. Simulation results suggest that continuation of over extraction of groundwater will gradually increase the depletion volume in the river year after year and more depletion will occur in later years. The exchange manner between groundwater and the Platte River differs from place to place. The Platte River loses water to the adjacent aquifer in the west part of the study area, and gains water from the adjacent aquifer in the east part of the study area.

Spatial Assessment of Water Quantity Stress in Sultanate of Oman Provinces: A GIS Based Analysis of Water Resources Variability

Water quantity planning and management require understanding of spatial variations of water catchment availability. Several environmental indicators are associated with water quantity such as flood occurrence, drought severity, seasonal supply and groundwater stress. Analyzing water stress at national geographic scale is crucial to detect and explore geographic shortage of water resources at national scale. In this study, Geographical Information Systems (GIS) techniques were employed to analyze the spatial variations of water scarcity across Sultanate of Oman provinces. For this main objective, various spatial and attribute datasets were prepared. Many variables were selected based on their importance and correlation with water quantity. GIS overlay function then was used to produce maps for each water indicator. This was followed by employing raster zonal statistics to aggregate the values of each catchment area within each province. The findings of this analysis indicated that significant spatial variation was found among Omani provinces in terms of water quantity stress and its determinants. The most important factors affecting the water quantity stress were drought severity and flood occurrence. Furthermore, physical risk of water quantity was higher in Mascut and Dhofar provinces while it was moderate in Al-Batinah, A’Dakhiliyah and Al-Wusta. Lower risk of water quantity was observed in A’Sharqiyah, Masandam, and A’Dhahriah provinces. Thus, in order to mitigate the impacts of water scarcity on agriculture, cultivation and domestic usages, policy makers in water sector should include spatial strategies for water resource maintain and allocation.

Some Indicators of the Water Regime in Some Varieties Belonging to the Monarda didyma L. Genus in the Conditions of Tashkent (Uzbekistan)

In this article, the names of 3 varieties of Monarda didyma L., which are considered to be introduced species, some indicators of the water regime in the climatic conditions of Uzbekistan: the amount of water in the leaves, water deficit, water storage capacity were studied in spring and summer, and seasonal changes were determined. According to these indicators of the water regime, the studied varieties belong to the labile water regime, high green mass (centner), seed yield (how many grams), resistance to diseases and pests have been determined, which shows that it is promising for introduction in the conditions of our republic. Therefore, it is recommended to breed these varieties in the foothills and hilly regions of Uzbekistan, where the amount of precipitation is more than 400 - 500 mm.

Perceptions of Bark Beetle Landscape Disturbance Effects on Natural Resources and Drinking Water: Assessing Communication and Knowledge Exchange in the Rocky Mountain Region, USA

Widespread changes to forested watersheds affected by the mountain pine beetle (Dendroctonus ponderosae Hopkins) epidemic across western North America raised concerns about the effects of this climate-induced disturbance on drinking water and natural resources. Effective communication and knowledge exchange across scientists and stakeholders (i.e., drinking water managers) is essential for constructively responding to such landscape scale disturbances, providing improved adaptive capacity through knowledge sharing. An assessment of stakeholder knowledge levels, information needs, primary concerns, and suggested communication strategies were conducted via an online elicitation survey and World Science Café workshops. Knowledge levels, assessed via a survey of local water managers and experts, were relatively low with approximately half of the respondents reporting little to no knowledge of the effects of mountain pine beetle on drinking water quality and quantity, thereby indicating limited knowledge exchange between scientists and drinking water stakeholders. Increased accessibility and dissemination of research findings pertinent to the mountain pine beetle epidemic’s effects on drinking water quality and quantity is necessary for natural resource management. Recommendations for improved communication among scientists and drinking water stakeholders in particular and forest health in general include dispersal of non-academic research summaries, information exchange through existing media and community resources, demonstration projects, and information clearinghouses. This information provides a better understanding of the challenges, concerns, and first-hand experience of stakeholders of a landscape disturbance issue to apply this knowledge to enhance land management practice and how researchers on this overall project enhanced science communication efforts.

The Effect of Mineral Composition and Quantity of Fines on the Atterberg Limits and Compaction Characteristics of Soils

Because of the various elements that come into play in natural soil formation, the impact of varied proportions of mineral composition and fines amount on Atterberg limits and compaction characteristics of soils is not well known. Three distinct soil samples were used in this investigation. The findings indicated the effect of varied mineral composition proportions and fines amount on the liquid limit, plastic limit, and plasticity index as assessed by the Casagrande test and hand-rolling method. The fluctuation of maximum dry density and optimal moisture content with these three soils has also been studied. Furthermore, correlations were established to indicate the compaction parameters and the amount of minerals and particles in the soil. The data show that the mineral content of the soil has a direct impact on the Atterberg limits and compaction characteristics. Soils containing larger percentages of expansive minerals, such as montmorillonite, have more flexibility and volume change capability. Mineral composition influences compaction parameters such as maximum dry density, ideal water content, axial strain, and axial stress. Soils with a larger proportion of fines, such as Soil 2 and Soil 3, have stronger flexibility and lower compaction qualities, with higher ideal water content and lower maximum dry density. Soil 1 has moderate flexibility and intermediate compaction qualities due to its low fines percentage. The effect of different mineral compositions and fines on the Atterberg limits and compaction characteristics of soils can be used to predict the behavior of compacted soils encountered in engineering practices, reducing the time and effort required to assess soil suitability for engineering use.

新能源汽车产业园区工业废水特征及处理模式

新能源汽车已成为我国“新质生产力”的代表。对新能源汽车产业的废水水质特征、产业门类工业废水水量指标、处理模式以及重点污染物处理方法等进行了归纳总结。新能源汽车废水污染物成分复杂、有毒性、难以直接生化处理,废水中主要含有表面活化剂、矿物油、磷酸盐、重金属等污染物。通过梳理行业21家重点企业的环境影响评价报告得出,新能源汽车产业废水主要由整车制造、储能装置制造等企业产生。从政策层面上看,当新能源汽车产业形成集聚效应和规模效应时,园区建设配套废水处理厂具有必要性。废水中的重金属离子、表面活化剂等特征污染物需要在预处理阶段重点考虑,提高废水的可生化性,建议尽快将重金属废水处理新技术应用于实际新能源产业废水处理工作中,加大绿色环保型表面活性剂的研发力度。各地需根据园区现状产业及发展规划等,提前做好水质水量分析,有针对性地处置重点污染物,同时也需在园区招商引资、企业废水监管、废水处理收费等方面多加考虑。

ON REGIONAL DIFFERENTIATION OF RIVER WATER ENVIRONMENT CAPACITY AND STRATEGIES TO CONTROL WATER ENVIRONMENT POLLUTION IN CHINA

China has large population and wide territory, the natural conditions of different regions are complicated. water resources are distributed unbalanced.economic developing states are unequal. For these reasons the variation of concerned water environment capacity has obvious character of regional differentiation. In this paper, from the economic development point of view, the regular pattern of regional differentiation of China's water environment capacity resources is analyzed. the concept of contradictory degree between water environment capacity and economic development is introduced, based on them, rivers in China are divided into three regions, and corresponding strategies to control water pollution are advanced. The aims are to use river water environment capacity resources effectively. to control pollution and to improve environmental quality.

Coupling Effect of Water and Phosphate on Economic Traits of Sugarcane

[Objective] The aim was to study the coupling effect of water and phosphate on economic traits of sugarcane. [Method] Taking sugarcane variety ROC22 as tested material,coupling effects of different levels of water supply quantity and different levels of phosphorus fertilizer on the yield and quality of sugarcane were studied. Among them,water supply quantity had 3 levels,that was,the water supply quantity per 10 days from the early tillering stage of sugarcane to the end of elongation was 199.5 m3/hm2 (A1),400.5 m3/hm2 (A2) and 600.0 m3/hm2 (A3),respectively; Phosphorus fertilizer as basic fertilizer had 4 levels:P2O5 0 kg/hm2 (B1),120 kg/hm2 (B2),240 kg/hm2 (B3) and 360 kg/hm2 (B4). [Result] Treatment A3B2 in water-fertilizer coupling was more suitable to improve economic traits of sugarcane. [Conclusion] The research results provide theoretical basis for the efficient utilization of water and phosphorus fertilizer in production of Guangxi sugarcane and the cultivation of high-yield and high-glucose sugarcane.

ANALYSIS AND CALCULATION OF REGULATED WATER RESOURCES OF GROUNDWATER RESERVOIR

Groundwater reservoir is a kind of important engineering, which can optimize water resources arran- gement by means of artificial regulation. Regulated water is the blood and value performance of groundwater reservoir. To resolve the problem of real-time quantification of regulated water, the paper analyzed sources and compositions of regulated water in detail. Then, under the conditions of satisfying water demand inside research area, the paper analyzed quantity available and regulation coefficient of different regulated water and established a formula to calculate regulated water. At last, based on a pore groundwater reservoir in the middle reaches of the Yinma River, Jilin Province, the paper calculated regulated water with the formula and the result shows that the method is feasible. With some constraint conditions, the formula can be adopted in other similar areas.

Mechanism of Photothermal Energy on the Growth and Yield of Rice under Water Level Regulation

The flooding caused by heavy rainfall in rice irrigation area and the drought caused by the drop of groundwater level are the research focus in the field of irrigation and drainage.Based on the comparative experiment and farmland water level control technology,this paper studied the average soil temperature under different soil layers(TM),the daily temperature change(TDC),the photosynthetic accumulation of single leaf and canopy in rice,and response of photothermal energy to rice root characteristics and growth factors in the paddy field under drought conditions.The results showed that the peak soil temperature under drought treatment was basically synchronous with the conventional irrigation,and the it was delayed by 2–6 h under flooding treatment compared to the drought treatment.Under different water gradients,the temperature decreased according to T_(L)>T_(CK)>T_(H)(L,H and CK represented water flooding,drought and control treatments),and the TDC was opposite.In addition to milky stage,the daily photosynthetic(Pn)accumulation of single leaf and canopy in the flooding and drought treated paddy fields were lower than conventional irrigation,and had a negative impact on leaf area index(LAI)and yield(YR),but did not form fatal damage.The root characteristic factors,RL(root length),RW(root weight),R-CR(root-canopy ratio)were promoted with drought,and YR under light drought was slightly higher than that under heavy drought.There was a strong positive correlation between TM and R-CR in all rice growth stages,while TDC-5 was negatively correlated with effective panicle number,TDC and R-CR in 20 cm soil layer were positively correlated.The correlation between daily Pn accumulation and YR was low,and the correlation between Pn and YR factors was negative or weak positive or negative.The total Pn was positively correlated with yield factors,and the correlation coefficient was higher than that of daily Pn.

Solution and its application of transient stream/groundwater model subjected to time-dependent vertical seepage

Based on the first linearized Boussincsq equation, the analytical solution of the transient groundwater model, which is used for describing phreatic flow in a semiinfinite aquifer bounded by a linear stream and subjected to time-dependent vertical seepage, is derived out by Laplace transform and the convolution integral. According to the mathematical characteristics of the solution, different methods for estimating aquifer parameters are constructed to satisfy different hydrological conditions. Then, tile equation for estimating water exchange between stream and aquifer is proposed, and a recursion equation or estimating the intensity of phreatic evaporation is also proposed. A phreatic aquifer stream system located in Huaibei Plain, Anhui Province, China, is taken as an example to demonstrate tile estimation process of the methods stated herein.

Water Consumption in Ningxia Reach of the Yellow River since Integrated Regulation

The annual allocation, inter-annual variation and relation of water diversion and recession are analyzed in Ningxia reach of the Yellow River main stream from 1999 to 2012. Water consumption in Ningxia reach was calculated by water diversion-recession method and water balance method. The average value of water diversion-recession method is 3.264 billion m3 and annual varia-tion is relatively steady. The result of water balance method is 3.937 billion m3 and annual variation is obvious. It is suggested that strengthen verification of entrances and monitoring of water diversion and recession.

Hydrological Systems in the Greater Virunga Landscape: Water Quality around Mikeno Sector

Monitoring of environmental parameters is one of the highest priorities in the evaluation of environmental status of water resources and in environmental protection policy. The main objectives are to understand and evaluate the water quantity and quality in order to provide water of appropriate quality to various water users. The water quantity was assessed by the measurement of runoff or discharge at specific river cross sections using floating method for surface water and bucket and stopwatch method for springs and boreholes. The quality of river water and spring was identified in terms of its physical, chemical, and biological parameters. The analyzed data were compared with standard values recommended by WHO. Macroinvertebrates were collected in the rivers using a plankton nets and 10 minutes of sampling. Identification was made at the laboratory of Malacology. Results revealed that the quality of water obtained from sampling points is generally good to use for different domestic purposes except the Idanta River and Rwembwe borehole, which need an appropriate treatment before use. All sampling points are located far from houses and latrines, which can contribute to fecal contamination. On the different sampling points, bathing and washing clothes were observed and could constitute the source of pollution of drinking water. In Idanta and Kamira Rivers animals used water for drinking while also people use this water for domestic and drinking. In the two sampling points high values of Escherichia coli were found. No pollutant-taxa tolerant were found in the two monitored rivers for macroinvertebrates. Since water quality and quantity remain a major challenge in rural areas, the government should provide safe water to the population around Mikeno sector after treatment using suitable techniques.

Water Problems in Gaza Strip,Palestine

The only source for water in Gaza strip, southern Palestine, is the groundwater aquifer. The Pliocene-Pleistocene aquifer has two serious problems: quantity and quality. This study is an attempt to identify the problems and to suggest solutions for water problems in Gaza strip. In addition, some rules for rehabilitation of the aquifers were suggested.

Characteristics of an Explosive Cyclone over Northeast China Revealed by Satellite Water Vapor Imagery

In this paper,an explosive cyclone(EC)that occurred over Northeast China in the spring of 2016 is studied by using 6.7μm FY satellite water vapor(WV)imagery and NCEP(1°×1°)reanalysis data.Moreover,the evolutions of the upper-level jet stream(ULJ),the vertical motions,and the potential vorticity(PV)are analyzed in detail.Results show that different shapes of the WV image dark zones could reflect different stages of the EC.At the pre-explosion stage,a small dark zone and an S-shaped baroclinic leaf cloud can be found on the WV imagery.Then the dark zone expands and the leaf cloud grows into a comma-shaped cloud at the explosively developing stage.At the post-explosion stage,the dark zone brightens,and the spiral cloud forms.The whole process can be well described by the WV imagery.The dynamic dry band associated with the sinking motion and the ULJ can develop into the dry intrusion later,which is an important signal in forecasting the EC and should be paid attention to when analyzing the WV imagery.Furthermore,the mechanism is also analyzed in detail in this article.EC usually occurs in the left-exit region of the 200-h Pa jet and the region ahead of the 500-h Pa trough where there is significant positive vorticity advection(PVA).When the EC moves onto the sea surface,the decreased friction would favour the development of the EC.The upper-level PVA,the strong convergence at low level,and the divergence at high levels can maintain the strong updraft.Meanwhile,the high PV zone from the upper levels extends downward,approaching the cyclone.Together,they keep the cyclone deepening continuously.

皖南农村地区需水量特征分析及预测模型研究

需水量的准确预测对于提高农村地区水资源利用率、优化农饮水厂日常调度有着重要作用,然而现有预测算法面临农村部分地区可用历史数据少、质量差等问题,同时部分预测算法的计算负荷较高,无法有效适应农饮水厂运维环境。选取2021-2022年安徽省南部不同地区3处农饮水厂日供水量数据作为研究对象。经过特征分析发现,皖南农村地区日需水量存在季节性变化趋势明显而短期内波动较大的特点。针对该数据特点及实际计算需求,选取了使用网格搜索法优化后的ARIMA模型进行预测,并与SVR、LSTM、RF等模型进行对比分析。研究结果表明,使用网格搜索法的ARIMA模型可以更好地适应农饮水厂运维环境,利用其对于周期性、季节性数据较强的学习能力,对农饮水厂供水量变化趋势和规律进行准确预测,具有一定的普适性,且计算负荷明显优于其他方法。模型对比分析显示,ARIMA模型的预测精度最高,在3处农饮水厂测试集数据上的平均绝对百分比误差(MAPE)分别为1.827、1.454、2.714。