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.

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.

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.

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。

太湖流域洪水与水量调度方案修订的认识与思考

太湖流域经济社会的快速发展对流域调度工作提出新的更高要求。回顾了《太湖流域洪水与水量调度方案》实施以来流域防洪与水量调度的实践,总结分析了方案修订背景、总体考虑以及修订的主要内容,并作出展望与思考。

油水气混合的数字化微量润滑装置

微量润滑装置对油水气量的准确控制及其雾化效果,将直接影响切削冷却效果,进而影响零件加工质量。为改善微量润滑装置的辅助切削效果,研制了一种具有油水气混合的数字化微量润滑装置,有效改善了润滑油雾喷射的连续性和均匀性。基于微量润滑雾化技术,设计开发了数字化微量润滑装置,搭建铣削工艺实验平台,测试新型微量润滑装置的辅助切削效果。结果表明,所研制的油水气混合的数字化微量润滑装置能够明显提高油雾质量和辅助切削效果。

水资源“量-质-域-流-生”全要素保护体系架构与实施策略

水资源保护是关乎民生福祉和国家安全的重要基础性工作。在新时期生态文明和美丽中国建设背景下,水资源保护亟需向流域化、系统化、生态化方向发展。研究基于对水资源系统多维属性功能的解析,从流域整体视角剖析了人类活动对水资源系统的干扰特征,提出了水资源“量-质-域-流-生”全要素保护策略,明确了水资源全要素保护的概念、内涵及体系架构。进一步,从服务于我国水资源管理实践角度,提出了以“退水还河、退污还清、退地还盆、退堵还疏、退渔还生”为核心的水资源全要素保护策略,明确了东北地区、黄淮海地区、长江中下游地区、东南沿海地区、西南地区、西北地区的水资源保护核心要点。最后,从政策法规、制度建设、监管体系等提出了推进我国水资源全要素保护的对策与措施。研究成果是对传统水资源保护工作的有益发展,为新时期国家治水实践提供了有力抓手。

地下水超采管控体系及水量水位双控体系研究进展

以《地下水管理条例》中空间管控和目标管控思想为指导,分类梳理了地下水超采管控体系和水量水位双控体系的研究进展及现状。地下水超采管控体系研究与我国具体国情结合日益紧密,但目前相关管理制度与规范仍亟待完善;地下水超采管控体系明确了已发生超采区域的划分标准,但缺少统一且全面的地下水资源管控区划标准;地下水水量水位双控体系克服了由于水位或水量单方面控制、未考虑地下水水位与水量的内在联系、难以有效缓解由水位或水量变化而导致的生态环境问题的局限性;水量水位双控体系研究的难点在于通过监管点状分布的水位控制面状分布的开采量,建议通过管理特定时间的水位控制一定时段的地下水开采量,或通过管理面状开采量来对点状水位进行控制。

中国水资源综合利用水平的地区差异与动态演进

水资源日益成为制约中国经济高质量发展的重要瓶颈。基于水质水量耦合的视角,利用中国除中国香港、澳门、台湾外的31个省(自治区、直辖市)的省级面板数据对中国水资源综合利用水平进行测度,分析地区差异及来源,并探究其时空演化规律。从区域差异特征看,全国及四大区域水资源综合利用水平呈波动上升趋势,利用水平依次为:东部>中部>东北>西部,总体呈现“自西向东不断先上升后略有下降,自南向北先上升后下降”的分布趋势;从变动情况看,绝对差异呈缩小的趋势,差异主要由地区间差异贡献,贡献率为53.72%;部分西部省区市拉低了整体的水资源综合利用水平;“邻居”水平具有正向的空间溢出效应。研究对促进我国经济社会高质量发展、提升水资源综合利用水平具有重要意义。

水质臭氧分析仪校准系统介绍及溯源方法研究

研制水质臭氧分析仪的校准系统,并对其进行不确定度评定,使用紫外分光光度计,对臭氧水的吸光度定值和摩尔吸光系数用碘量法进行量值溯源。结果表明:该系统稳定性为3%/10min,扩展不确定度为0.05mg/L,k=2,可用于该分析仪的校准。

基于时间序列模型ARIMA的校园供水管网暗漏检测研究

为了及时发现校园供水管网暗漏情况,减少水资源浪费和降低暗漏检测成本,在获取校园各区域水表数据的基础上,根据学校用水规律及特点,建立基于时间序列模型ARIMA的用水量预测模型,分析预测用水量与实际用水量之间的差异性,进而判断校园供水管网是否存在暗漏,构建校园供水管网暗漏检测模型。结果表明,基于时间序列模型ARIMA的校园供水管网暗漏检测模型判断正确率为80%,实际应用效果良好,可以作为校园供水管网暗漏检测的一种预警方法。此方法是基于水表数据的数据模型方法,省时省力省钱,并且可以拓展到其他场所使用。

黄河流域煤矿矿井水综合利用问题分析及管控建议

黄河流域煤炭资源丰富,但水资源匮乏,如何在确保生态环境安全的前提下,最大程度实现煤矿矿井水的综合利用,成为该地区迫切需要解决的热点问题.黄河流域煤矿矿井水的涌水量分布不均,呈南多北少的特征,且水质具有高矿化度、碱性或弱碱性以及高氟化物的特点.结合当前煤矿矿井水主要的综合利用途径,在总结国内外煤矿矿井水排放管控要求的基础上,识别当前制约我国煤矿矿井水综合利用的原因包括外排受较多制约,缺少供水需求,缺少对水质标准、技术规范和政策监管的改善,处理过程中缺乏技术规范化指导以及缺乏鼓励矿井水综合利用的措施等.针对以上问题,从实事求是地制订煤矿矿井水外排的管理要求、科学制订基于不同利用途径的煤矿矿井水综合利用水质标准、加强煤矿矿井水处理技术的推荐和引导以及建立多部门协作机制等方面,提出提高黄河流域煤矿矿井水综合利用率的建议,以期为合理利用水资源、确保生态环境安全、促进黄河流域高质量发展提供支撑.

湖北省村镇污水特征与污水处理设计研究

文章选取湖北省宜昌市及周边县市山区、丘陵和平原等典型地貌特征农民居住点为调研对象,通过对分散农户在日常生活产生的黑水和灰水分别进行收集、在采样和水质指标分析的基础上,分别研究了湖北省村镇生活污水中黑水和灰水的水量产生特征、水质分布特征以及各自的主要影响因素。结果表明,黑水和灰水水质影响因素复杂,其中农户生活习惯及与之相关的多种因素的综合影响相对显著;由于农村污水收集及预处理方式不同,导致集中站点进水与农村分散户排水水质间存在显著差异。

钛合金铣削加工中MQL参数优化与切削性能研究

微量润滑(MQL)铣削过程中,系统工艺参数对刀具–切屑和刀具–工件间接触界面的冷却润滑效果影响显著。本文通过有限元仿真分析了铣刀高速旋转扰动的空气流场对MQL喷射角度的影响以及切削区压力影响下的切削液渗透机理。然后,以钛合金TC4为工件材料、油膜附水滴(OoW)为润滑介质,通过正交试验研究微量润滑系统喷射角度、喷射距离和润滑油流量对铣削力的影响规律,获得油膜附水滴微量润滑(OoWMQL)系统最佳工艺参数为:喷嘴俯角30°、喷射距离10 mm、润滑油流量135 mL/h。基于此,采用OoWMQL系统最优工艺参数,开展干式铣削和水基微量润滑(WMQL)铣削下切削速度、每齿进给量对钛合金切削性能的影响研究。结果表明,相比干式铣削,WMQL方法对铣削力的改善效果较弱,而OoWMQL方法在所有参数下均明显降低了铣削力,且降低幅度最高可达50%左右。此外,采用OoWMQL方法可显著降低表面粗糙度,抑制划痕和粘屑等表面缺陷的产生,有效提高钛合金的切削加工性。

景观格局汇水单元法与城区水量水质模拟研究

景观多样性有助于提高城市韧性,但其可能带来的透水斑块破碎化和廊道连通度的改变,会影响城区非点源污染的产生输移特性。传统对非点源污染的定量评估忽略了汇水单元内部景观格局(形状、比例和空间配置)对物质输移的影响,是导致模拟精度偏低的主要原因。针对这一问题,本研究结合遥感影像和城市景观格局分布特征,构建了基于景观格局的汇水单元划分方法(景观格局法)。采用SWMM模型,以巢湖一级支流十五里河为对象展开研究,结果表明:(1)基于实测数据进行验证,采用景观格局法模拟各项指标(水量、COD、TP和NH 3-N)的纳什效率系数(NSE)均大于0.7,结果可靠;(2)与传统方法(泰森多边形划分汇水单元)相比,水量模拟精度(以NSE计)提高8%,水质模拟精度提高6%;(3)与泰森多边形法相比,景观格局法计算的入河总水量和污染总负荷较低,且污染物浓度峰值滞后;(4)景观格局法通过改变汇水单元之间的水力联系,模拟出污染物冲刷减弱,初期雨水冲刷效应降低,且随着重现期的加大,降低初期雨水冲刷强度的效果越明显,表明一定程度上景观类型多样化有助于缓解瞬时高强度污染影响。本研究构建的方法充分考虑了城市斑块内部的景观格局分布特征和水力联系,可为城区面源污染输出控制提供新的评估手段。