Blue and Grey Water Footprints of Dairy Farms in Kuwait

In Kuwait, dairy farming faces challenges due to its significant water demands. The current study assessed seasonal patterns of water use to estimate the blue water footprint (WF) and grey WF per kg of fat protein corrected milk (FPCM) for confined dairy farming systems in Kuwait. Blue and grey WFs were evaluated using data from three operational farms. The average blue WF (L·kg-1 FPCM) was estimated to be 54.5 ± 4.0 L·kg-1 in summer and 19.2 ± 0.8 L·kg-1 in winter. The average grey WF (generated from milk house wastewater) was assessed on bimonthly basis and determined based on its phosphate (PO4) concentration (82.2 ± 14.3 mg·L-1) which is the most limiting factor to be 23.0 ± 9.0 L·kg-1 FPCM d-1. The outcomes indicate that enhancing the performance of dairy cows and adopting alternative water management strategies can play a role in minimizing the impacts of confined dairy farming systems in Kuwait on water quality and quantity.

Modification of Grey Water Treatment Using Combination of Cascade Aeration and Biofiltration

A combination of cascade aeration and biofiltration systems is one of the available ecological treatments to reduce the concentration of pollutants in grey water and resolve the problem of acute water crisis supply in Iraq. An experimental constructed grey water treatment system has been installed at AI-Mustansiriya University, College of Engineering during the period from January to December 2012. The performance of the treatment schemes has been evaluated by monitoring the quality of the raw grey water and effluent on these samples which are： pH, COD （chemical oxygen demand）, TSS （total suspended solids）, TDS （total dissolved solids）, PO43 （phosphates）, NO32 （nitrates）, NO （nitrites）, oils ＆ grease, NH3-N （ammonia-nitrogen） and some anions and cations. The average removal rate of COD was more than 60% that of NH3-N, NO3-N, NO2-N, TDS and TSS that were 55%-89%, 59%-74%, 79%-98%, 17%-52% and 51%-87%, respectively. Also the results indicate that the removal efficiency of ions concentrations such as Ca2＋, Mg2＋, Na＋, K＋ were 78%-96%, 73%-97%, 14%-47% and 44%-64%, respectively, while for cations such as SO42, Cl and PO43-, the removal efficiencies were 33%-79%, 27%-61% and 81%-99%, respectively. Finally oils ＆ grease was 79%-88%.

Preliminary Calculation of a Natural System Based Treatment Plant for Grey Water from Butare Central Prison, Rwanda

After the chemical and biological analyses of grey water from Butare Central Prison in Butare city, District of Huye, southern province of Rwanda, the resulting data were used in preliminary calculations of a natural system based treatment facility. In our region, natural systems, lagoons and constructed wetlands were identified as potential effective technologies for wastewater treatment due to the low cost and favorable climate. In our study, the authors calculated two systems of treatment plants, one based on two ponds associated with a constructed wetland and another based on three ponds. This study aims at raising awareness of the required land surface that can allow the use of extensive technologies in treating domestic wastewater from the prison. Depending on the system and on the design equation used, those systems differ from their dimensions. Those systems led to overall surface areas between 0.6 ha and 1 ha. In the next stage that will take an interest in studying the feasibility of the project, the decision will be made in favor of one of the calculated systems in compliance with the accuracy and site specifications that are still to be studied.

GREY WATER RECYCLING FOR REUSE IN TOILET FLUSHING: A CASE STUDY IN THAILAND

Grey water from washbasins represents the least polluted source of waste water in households and buildings. This research study investigated three alternatives in recy-cling grey water from washbasins for reuse in toilet flushing systems. Grey water was collected from the washbasins of a nine-storey university building. The water was treated employing three distinct treatment systems in order to determine the most appropriate system when reusing such water in flushing systems. The grey water treatment systems under scrutiny were composed of a sedimentation tank, a 24-hour aeration tank and a sand and carbon filtering tank, functioning in conjunction with a final sedimentation tank. The water quality from the selected treatment system had TSS, BOD_(5), and Turbidity measures of 1.67 mg/l, 3.33 mg/l, and 3.33 NTU, respectively. Fecal coliform bacteria and E. Coli were not found in the treated water. Efficiency measures in reducing TSS, BOD_(5), and Turbidity were 93%, 75%, and 91%, respectively. Fifty-five toilet users were interviewed during the experiment, sixty nine percent of which reported that the recycled water was comparable to tap water. In conclusion, this research recommends treating grey water from washbasins and reusing it in flushing systems in order to deploy water more efficiently in buildings.

Environmental sustainability of grey water footprints in Peshawar Basin:Current and future reduced flow scenarios for Kabul River

Assessing water pollution at basin level is a challenging task.In this study,the environmental sustainability of grey water footprints(WFgrey)of Peshawar Basin in Pakistan was analysed.The release of nitrogen(N)and phosphorus(P)from point and non-point sources during the period 1986 to 2015 were studied.Water pollution level(WPL)for normal and 10%-50%future reduced runoff in Kabul River as a result of construction of dams was considered.Methodologies described in Water Footprint Assessment Manual and Grey Water Footprint Accounting Guidelines were followed.Results showed that 30-year annual average of N and P discharges were 24.5×10^(3)t/a and 10.9×10^(4)t/a respectively.The discharge of N and P from non-point sources contribute 97%and 99%respectively.N related WFgrey was 50×10^(8)m^(3)/a and 50×10^(9)m^(3)/a for P.WPL of N was within the sustainable limit for all reduced runoff scenarios while P-related WPL for normal runoff exceeded sustainable limits and was worse in each reduced runoff scenario.This study confirms the deteriorated water quality of Kabul River and the findings may be helpful for future planning and water resource management of the basin.

Use of oleaginous plants in phytotreatment of grey water and yellow water from source separation of sewage

Efficient and economic reuse of waste is one of the pillars of modern environmental engineering. In the field of domestic sewage management,source separation of yellow（urine）,brown（faecal matter）and grey waters aims to recover the organic substances concentrated in brown water,the nutrients（nitrogen and phosphorous）in the urine and to ensure an easier treatment and recycling of grey waters. With the objective of emphasizing the potential of recovery of resources from sewage management,a lab-scale research study was carried out at the University of Padova in order to evaluate the performances of oleaginous plants（suitable for biodiesel production）in the phytotreatment of source separated yellow and grey waters. The plant species used were Brassica napus（rapeseed）,Glycine max（soybean）and Helianthus annuus（sunflower）. Phytotreatment tests were carried out using 20 L pots. Different testing runs were performed at an increasing nitrogen concentration in the feedstock. The results proved that oleaginous species can conveniently be used for the phytotreatment of grey and yellow waters from source separation of domestic sewage,displaying high removal efficiencies of nutrients and organic substances（nitrogen 〉 80%; phosphorous 〉 90%; COD nearly 90%）. No inhibition was registered in the growth of plants irrigated with different mixtures of yellow and grey waters,where the characteristics of the two streams were reciprocally and beneficially integrated.

The Application of a Grey Markov Model to Forecasting Annual Maximum Water Levels at Hydrological Stations

Compared with traditional real-time forecasting,this paper proposes a Grey Markov Model(GMM) to forecast the maximum water levels at hydrological stations in the estuary area.The GMM combines the Grey System and Markov theory into a higher precision model.The GMM takes advantage of the Grey System to predict the trend values and uses the Markov theory to forecast fluctuation values,and thus gives forecast results involving two aspects of information.The procedure for forecasting annul maximum water levels with the GMM contains five main steps:1) establish the GM(1,1) model based on the data series;2) estimate the trend values;3) establish a Markov Model based on relative error series;4) modify the relative errors caused in step 2,and then obtain the relative errors of the second order estimation;5) compare the results with measured data and estimate the accuracy.The historical water level records(from 1960 to 1992) at Yuqiao Hydrological Station in the estuary area of the Haihe River near Tianjin,China are utilized to calibrate and verify the proposed model according to the above steps.Every 25 years' data are regarded as a hydro-sequence.Eight groups of simulated results show reasonable agreement between the predicted values and the measured data.The GMM is also applied to the 10 other hydrological stations in the same estuary.The forecast results for all of the hydrological stations are good or acceptable.The feasibility and effectiveness of this new forecasting model have been proved in this paper.

Environmental Sustainability of Water Footprint in China' Mainland

Water footprint(WF)measures human appropriation of water resources for consumptive use of surface and ground water(blue WF)and soil water(green WF)and for assimilating polluted water(grey WF).Questions have been often asked about the exact meaning behind the numbers from WF accounting.However,to date environmental sustainability of WF has never been assessed at the sub-national level over time.This study evaluated the environmental sustainability of blue,green and grey WF for China’s 31 mainland provinces in 2002,2007 and 2012,and identified the unsustainable hotspots.Overall,the total WF increased by 30%between 2002 and 2012.The growth can be attributed to the increase of grey WF because the green and blue WF showed only a slight rise.Among all provinces investigated in 2012,eleven showed unsustainable blue WF(sustainability index SI<0),which were mainly located in the North China Plain.There were 12 provinces that displayed unsustainable green WF,and they were distributed in China’s southern and southeastern areas.The grey WF was not sustainable in approximately two third of provinces(19),which were mainly located in China’s middle and northern regions and Guangdong province.More than half of China’s provinces showed trends of improved SI of green and blue WF from 2002 to 2012.However,the SI of grey WF decreased in almost two third of provinces.Poor levels of WF sustainability were due to water scarcity and pollution,which intensify the degradation of local rivers and ecosystems and make restoration more difficult.The results shed light on the policy making needed to improve sustainable water management,and ecological restoration of hotspot regions.

Agricultural Water Footprint of Southern Highbush Blueberry Produced Commercially with Drip Irrigation and Sprinkler Frost Protection

A study was conducted from 2010 to 2017 to determine the water footprint for producing blueberries in the Entre Ríos province of Argentina. Three cultivars of southern highbush blueberry (hybrid cross of Vaccinium sp.) were evaluated in the study, including “Star”, “Emerald”, and “Snowchaser”. In each case, the plants were irrigated by drip and protected from frost using overhead sprinklers. Water requirements for irrigation and frost protection varied among the cultivars due to differences in the timing of flowering and fruit development. The annual water footprint for fruit production in each cultivar is expressed in units of cubic meters of water used to produce one ton of fresh fruit and ranged from 212 - 578 m3∙t−1 for “Star”, 296 - 985 m3∙t−1 for “Emerald”, and 536 - 4066 m3∙t−1 for “Snowchaser”. “Snowchaser” flowered earlier than the other cultivars and, therefore, needed more water for frost protection. “Star”, on the other hand, ripened the latest among the cultivars and required little to no water for frost protection. Frost protection required a minimum of 30 m3∙h−1 of water per hectare and in addition to drip irrigation was a major component of the water footprint.

Sustainable water system of a green residential zone:demonstrated with a case of a campus construction project

The sustainable water system (SWS) was interpreted based on green residential zone associated codes issued by P.R.China and some other countries,and ecological principles.Its constitution,designing and engineering,and economic and environmental benefits were illustrated with a case of a campus construction project.The SWS incorporates divided nature drainage systems,grey water treatment and reuse technologies,rainwater decentralized collection and purification technologies,and water quality safeguard techniques for reclaimed water reused for landscaping.Application of the SWS is expected to gain remarkable economic and environmental benefits by reducing both the demand for municipal water supply and sewage discharge.

Virtual Water Trade and Food Security for Iraq

Iraq depends on its water resources from the water of the Tigris and Euphrates Rivers and their tributaries. Now, the flow of these rivers is decreasing, and Iraq is experiencing a water shortage problem. The situation is expected to be graver in the future if no action is considered. It is expected that the population will be about 70 million in 2050 and about 90 million in 2070. In such a case, thus, the quantities of water available in the future will not be sufficient to produce most of the requirements of food security, whether that be from agricultural or animal products. To overcome this problem, water management planning should be based on scientific background to overcome the present and expected problems. One of the main factors to be considered should be based on scientific studies of the virtual water footprint of different food crops to provide the largest possible amount of virtual water and avoid the acute shortage of its national water from surface and ground irrigation water (blue water) and rainwater (green water), in addition to working hard to provide the largest possible amount of desalinated water and refined sewage (gray water). In addition, any strategic plan for sustainable development in the country must be comprehensive so that it is not satisfied with improving the situation in the field of food security related to water security, but rather among its other elements is community development that directly affects food security, including setting policies to reduce consumption by reducing the steady increase in population where the population rate is 2.97% now. Collective awareness and guidance programs in all the fields of water and food security are very important to be adopted, so that everyone knows that the issue of food security and what derives from it are an existential issue related to the survival of Iraq as a state and people. In this research, facts are stated so that action is to be considered to minimize the water shortage problem. The new strategic water resources management plan is to be adopted that considers existing and future expected problems.

Analysis of Agricultural Eco-Efficiency and Influencing Factors in Henan Province

In order to improve the agricultural eco-efficiency and promote the sustainable development of agriculture in Henan Province, China, based on the footprint theory, the super-efficiency SBM model is used to scientifically calculate and analyze the agricultural eco-efficiency in Henan Province. On this basis, the influencing factors of agricultural eco-efficiency in Henan Province are quantitatively analyzed by using the grey incidence analysis model. The results show that unilaterally considering one of grey water footprints and carbon footprints will overestimate or underestimate the agricultural eco-efficiency of Henan Province in different degrees in different time periods, and the agricultural eco-efficiency obtained by comprehensively considering grey water footprint and carbon footprint (GWCAEE) is more in line with the reality of agricultural development in Henan Province. In 2000-2004, GWCAEE in Henan Province was better. During 2005-2014, GWCAEE in Henan Province showed a fluctuating decline and continued to be in an inefficient state. From 2015 to 2019, GWCAEE of Henan Province gradually increased, and it became effective in 2019. In recent years, GWCAEE has developed well. Through the grey incidence analysis between 12 influencing factors including endogenous factors and exogenous factors and GWCAEE, it is found that the six leading factors of GWCAEE in Henan Province are agricultural structure, financial input for agriculture, number of agricultural employees, crop sown area, consumption of chemical pesticide, consumption of agricultural diesel oil. According to the above research conclusions, suggestions for improving agricultural eco-efficiency in Henan Province are put forward.

The Analysis of Water Footprint of Production and Water Stress in China

Water footprint of production can be used to identify pressure on national or regional water resources generated by production activities. Water stress is defined as the ratio of water use （the difference between a re- gional water footprint of production and a green water footprint） to renewable water resources available in a country or region. Water stress can be used to identify pressure on national or regional water resources generated by production activities. This paper estimates the water footprint of production and the water stress in China during the years 1985-2009. The result shows that China＇s water footprint of production increased from 781.58×109 m^3 in 1985 to 1109.76 × 10^9 m^3 in 2009. Mega-cities and regions with less agriculture production due to local climatic conditions （Tibet and Qinghai） had lower water footprint of production, while the provinces （Henan, Shandong） with higher agriculture production had higher footprint. Provinces with severe water stress increased from 6 in 1985 to 9 in 2009. High to severe water stress exists mainly in mega-cities and agricultural areas located in the downstream areas of the Yellow River and the Yangtze River in North and Central China. The outlook for water resources pressure in China is not optimistic, with areas of stress expanding from northern to southern of China.

纸张性能对水性油墨呈色性的影响

通过探讨纸张平滑度、光泽度和吸收性与呈色效果的关系,以及分析不同纸张上油墨的灰度、色偏、色效率等指标,得出铜版纸、胶版印刷纸以及新闻纸对水性油墨的影响,其中铜版纸的呈色性能最好,胶版印刷纸和新闻纸都比较差,且不同类型的胶版印刷纸对油墨呈色性又有很大不同。

Forecasting of dissolved oxygen in the Guanting reservoir using an optimized NGBM(1,1) model

An optimized nonlinear grey Bernoulli model was proposed by using a particle swarm optimization algorithm to solve the parameter optimization problem. In addition, each item in the first-order accumulated generating sequence was set in turn as an initial condition to determine which alternative would yield the highest forecasting accuracy. To test the forecasting performance, the optimized models with different initial conditions were then used to simulate dissolved oxygen concentrations in the Guantlng reservoir inlet and outlet （China）. The empirical results show that the optimized model can remarkably improve forecasting accuracy, and the particle swarm optimization technique is a good tool to solve parameter optimization problems. What＇s more, the optimized model with an initial condition that performs well in in-sample simulation may not do as well as in out-of-sample forecasting.