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Open access

Oleksandr Kvartenko, Larysa Sabliy, Nataliya Kovalchuk and Andriy Lysytsya

Abstract

The use of the biological method is promising for treating underground waters from iron compounds. Iron bacteria used in the process are widely spread in weak acidic and neutral underground waters containing iron ions (II), dissolved carbon dioxide and minimum concentrations of oxygen. The relevant direction of present-day biotechnology is the use of iron bacteria for treating underground waters. The goal of this research is to compare the efficiency of using the biological method for treating underground iron containing weak acidic and neutral waters under different conditions. As the test-objects, Gallionella and Lepthotrix iron bacteria were used. The sedimentation of bio-minerals was obtained from the washout waters of the biological deironing station. Calcium soda was used as an additional source of inorganic carbon for bacteria. As a result of the studies it is established that the use of the non-reagent method gives the possibility to achieve only 80% efficiency in removing iron compounds while the use of sodium carbonate results in increasing efficiency up to 93%. To determine the contribution of biological purification of ground water from iron compounds, the bacteria were inhibited with the preparation of polyhexamethylene guanidine (PHMG) chloride. It was found that inhibition of Gallionella and Lepthotrix led to the reduction of 50% of the iron removal effect. The mechanism was developed of inhibiting the process of iron bacteria metabolism by PHMG (polyhexamethylene guanidine). The new technology of arranging a block-module station for treating underground waters is proposed.

Open access

Serhii Martynov, Victor Fylypchuk, Vitalii Zoshchuk, Serhii Kunytskyi, Andrii Safonyk and Oleg Pinchuk

Abstract

Different types of filters are used to remove iron from underground water, one of them is foam polystyrene. Depending on the chemical water composition, tasks for water supply and other working conditions of iron-removing filters, it is necessary to define an exact grain size, specific granulometric composition, the thickness of the layer and the adequate rate of filtration. This kind of problems is multifactorial and its solution is based on the mathematical modelling.

As a rule, two parallel processes considered during iron removal of underground water in filters: efficiency of water treatment and growth of head losses. Therefore, the model of water iron removal based on two main blocks, clarifying block takes into account the material balance and kinetics of the process; hydrodynamic block describes the dynamics of head loss in the granular loading. The kinetics of the detention of iron compounds in granular loading consists of two mutually opposite processes. With an increase of the amount of adsorption-catalytic precipitate, the rate of sorption of iron compounds and oxidation of ferric iron increases and the efficiency of iron-removing increases. On the other hand, with decreasing porosity of loading the true velocity of the fluid increases, that reduces the intensity of adhesion of iron compounds.

Developed mathematical model allows for determining optimal values of structural and technological parameters of iron-removing filters taking into consideration the specific filtering conditions.

Open access

Marek Kopacz, Agnieszka Kowalczyk, Sylwester Smoroń and Zbigniew Ostrach

Abstract

The article presents the results of the analysis of water needs in agricultural production of the Grybów commune (the district of Nowy Sącz, the Małopolska province). The aim of this study was to determine both the current water needs for agricultural purposes as well as changes in this regard based on structural and production data. The guidelines specified in the Ordinance of the Minister of Infrastructure of 14 January 2002 concerning average norms of water consumption were applied to determine water needs. The average annual water demand of crops together with permanent grassland (meadows, pastures) amounts to 23.7 mln m3, of which about 2.15 mln m3 is for winter wheat, 1.92 mln m3 for potatoes and 17.6 mln m3 for permanent grassland. Significant amounts of water (over 130,000 m3) are used also for watering home gardens and cultivating vegetables in plastic tunnels and greenhouses. Water needs for animals farming reach about 235,000 m3 in a year. Most water is needed for farming the cattle. It is predicted that the demand for water in the agricultural sector of the commune will increase by about 5.5% by 2030. Therefore, the activities monitoring the awareness of water saving and proper water management among the population of the villages are important.

Open access

John W. Magugu, Song Feng, Qiuqiong Huang and Gilbert O Ototo

Abstract

Agro-forestry (AFR) technologies are perceived to improve livelihoods and natural resource sustainability of the rural households. Despite their aggressive promotion by multiple national and international agencies, the adoption of AFR technologies has been minimal in Kenya. This study conducted a survey to examine the socio-economic factors that affect the adoption process in Nyando, Kenya. Results revealed that farmers with bigger farms and higher education were more likely to adopt the new technology. Additionally, farmers were quicker to adopt technology if they had an increase in crop yields and had stayed longer in the study area. Generally, wealthier famers tended to adopt more AFR technology than those with less income. Access to information was the only factor strongly correlated with the rest of the independent variables. The results suggest that, adoption would be more enhanced with a clear focus on extension activities, income enhancing AFR practices and soil amelioration technologies. This study may be replicated in other parts of Kenya and East Africa to improve the level of AFR technology adoption for sustainable rural development.

Open access

Soufiane Dad and Tamara Benabdesselam

Abstract

The aim of the study is to improve the quality of estimating of the annual maximum daily precipitations of the northeastern area of Algeria. The regional frequency analysis based on L-moments was used. The investigated area is represented by 58 measuring stations. The main stages of the study were the definition of homogeneous regions and the identification of the regional distribution. It has been defined that the study region is homogeneous in terms of L-moments ratios despite the climatic differences within the region. Among the different tested distributions; the generalised extreme value (GEV) distribution has been identified as the most appropriate regional distribution for modelling precipitation in the region. The growth curve, derived from the regional distribution, was established. Therefore, to estimate the different return period’s precipitation quantiles in a given site of the region, the mean precipitation of the site has to be multiplied by the corresponding regional quantile (growth factor). Comparison of the quantiles estimated from the regional and at-site frequency analysis showed that in the majority of stations (82.8%) at-site model underestimates the quantiles having high return periods.

Open access

Mohamed F. Bekkouch and Ahlam Zanagui

Abstract

The Hamadian groundwater table ensures water supply for the agricultural perimeter of Wadi Mehiya region in the North-East of Tindouf city. In order to determine the behaviour of this groundwater table, a piezometric map have been realized, followed by physicochemical analyses to assess the chemical facies, the suitability of this water for irrigation and drinking purposes, as well as its vulnerability to different pollutants. This groundwater table is essentially composed of fine to coarse and clayey sands, surmounted by a silicified limestone slab. It is a free groundwater table with a thickness of 18 to 99 m. The sampling has been done in June 2010. Then, the physicochemical analyses have been performed on 7 samples taken from 7 boreholes. The piezometric study proved that the flow of groundwater table follows a North-East to South-West direction, towards the Sebkha of Tindouf. The graphic representation of chemical facies, using Piper and Schoeller–Berkaloff diagrams, reveals that the water of Wadi Mehiya contains mainly magnesium sulphate. The graphical representation of irrigation water quality, using Wilcox diagram, revealed an acceptable quality with a high salinity. Moreover, this water is potable with hard-mineralized character. Nitrates contamination has been also noted, which is a logical result of the excessive use of chemical fertilizers.

Open access

Fatima Z. Tebbi, Hadda Dridi and Mahdi Kalla

Abstract

Long term and mid-term reservoir operation involves derivation of rule curves for optimal management of the available resource. The present work deals with reservoir operation in the Aurès arid region. As an example, Babar reservoir is selected to apply the proposed approach which estimates all the water balance terms, especially those which are random as water inflows. For each demand scenario a reservoir operation optimization model using Explicit Stochastic Dynamic Programming (ESDP) is performed, to derive optimal rule curves based on historical operating records (Jan 2002–Dec 2013) and using “Reservoir” R package®. Subsequently, risk analysis is conducted for these different demand scenarios rules by the RRV (reliability, resilience, vulnerability) metrics. Results show the advantage of using the “Reservoir” R package for a rapid and an easy analysis of the performance criteria jointly with the optimization algorithm to Re-operate Reservoir operation.

Open access

Pitojo T. Juwono, Lily Montarcih Limantara and Fathor Rosiadi

Abstract

The irrigation area of Parsanga is located in Sumenep Regency, Madura Island of Indonesia. This irrigation area is 500 ha and the existing cropping pattern is paddy–paddy–second crop. There is water discharge deficiency due to the existing cropping pattern mainly in the dry season. Thus, this study intends to optimize the cropping pattern for 3 condition so that it can produce the maximum benefit of agricultural product. The first cropping pattern is paddy/second crop–second crop–paddy/second crop; the second proposition is paddy/second crop –paddy/second crop–second crop; and the third proposition is paddy–second crop–paddy/second crop. The optimization analysis is carried out by using the linear programming. The suggested three cropping patterns are not only able to solve the water deficiency; they can also present the more production benefit than the existing condition.

Open access

Saif Said, Rabab Siddique and Mohammad Shakeel

Abstract

Morphometric analysis of any watershed and its prioritization is one of the important aspects of planning for implementation of management programmes. Present study evaluates the quantitative morphometric characteristics of Nagmati River watershed in Kutch District of Gujarat by utilizing Cartosat-1 data (CartoDEM). In all 19 aerial and 6 linear morphometric parameters of the watershed have been evaluated. Drainage map of the study area reveals a dendritic drainage pattern with sixth order stream network comprising 492 numbers of streams and confining an area of 129.41 km2. Mean bifurcation ratio (Rb) and stream length ratio (RL) of the watershed evaluated are 3.44 and 0.54 respectively which corroborates the fact that drainage pattern is not influenced by the geological evolutions and disturbances in the recent past. The drainage density of 2.68 kmꞏkm−2 indicates impermeable subsoil material with sparse vegetation and moderate to low relief. Elongation ratio of 0.956 infers the basin to be closer to a circular shape. The geologic stage of development and erosion proneness of the watershed is quantified by hypsometric integral (HI) bearing value as 0.5, indicating the landscape to be uniform and in early mature stage. The study prioritizes eight sub-watersheds as high, medium and low for taking up soil and water conservation activities. Hence, remote sensing applications proved to be highly useful in extracting the precise data for the evaluation and analysis of watershed characteristics.

Open access

Andrii Bomba, Mykola Tkachuk, Volodymyr Havryliuk, Ruslan Kyrysha, Ievgenii Gerasimov and Oleg Pinchuk

Abstract

The situation when groundwater considerably rises above the “normal” level, water intake, lowering of groundwater levels and other relevant practical tasks require the drainage facilities. The most effective techniques of numerical studies of the corresponding boundary problems at present time are methods of dealing with inverse boundary value problems (conformal and quasi-conformal mappings). As basis of this research we used the case of combining the fictitious domain methods with quasi-conformal mappings of the solution of nonlinear boundary value problems for the calculation of filtration regimes in environments with free boundary areas (depression curves) and zones of “mountainous” areas.

This paper reviews the stationary issue of flat-vertical stationary non-pressure liquid filtration to horizontal symmetric drainage. In the paper a practical methodology for solving boundary value problems on conformal mappings is suggested for the calculation of the filtration process in the horizontal symmetrical drainage.

The idea of block iterative methods was used during the creation of the corresponding algorithm which is based on the alternating “freeze” of the anticipated conformance parameter, the internal and boundary connections of the curvilinear area.

The results of the conducted numerical calculations confirmed the effectiveness of the suggested problem formulations and algorithms of their numerical solution and the possibility of their use in the modelling of nonlinear filtration processes occurring in horizontal drainage systems, as well as in the design of drainage facilities and optimizing other hydrosystems. Therefore these results are of great importance.