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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.

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.

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.

Abstract

The aim of this study was to analyse the factors affecting agricultural water management in Iran based on irrigation experts’ point of view using factor analysis approach. The results indicated that conservation of modern irrigation equipment, promoting farmers’ knowledge, creating a watercourse (surface water collection), imposing a ban on digging new wells and educating the effectiveness of pressurized irrigation system were all known as the most important factors affecting agricultural water management. Moreover, factor analysis results showed that five factors influencing agricultural water management (institutional and legislative, educational and promotional, economic, technical and farming system) explained 64.29% of the total variance. At the end, some policy suggestions were provided in order to improve agricultural water management in Iran.

Abstract

The present work was designed to assess the contamination level in the coastal of Annaba, following the spectrophotometric determination of the level of some metallic elements (Fe, Cu, Pb, Zn, Ni and Cd) in the sediments along an increasing bathymetric gradient (10 m and 20 m), as well as in the biological indicator grey mullet (Mugil cephalus) muscle. During the winter period (2014), 12 surface sediment samples, and a total of 24 fish were collected. Once the samples are dried, crushed and sieved, 0.5 g dry weight of each sample was added to concentrated acids. The results showed that the levels of some metals are superior to the recommended guideline values, and consequently the sediment of this bay is contaminated by iron, lead and copper. The contamination index (CI) showed a general tendency in the concentration of the studied metals as follows: Fe > Pb > Cu > Zn > Ni > Cd, since the most studied metals occurred at higher concentration in depth (20 m).

However, the average concentrations of metals in fishes were found to be as the following order: Fe > Zn > Pb > Cu > Ni > Cd. The consumption of fish from some contaminated sites can be dangerous because concentrations of lead, cadmium and zinc exceed the international standards. Moreover, the strong positive correlation observed between the metallic elements of sediments and fishes confirm that these metals resulted from the similar sources of the anthropic activities, such as domestic, port, industrial and agricultural waste discharges. This is confirmed by the determined of pollution load index (PLI) parameter. Conclusively, a regular monitoring program of heavy metal is recommended for protecting these organisms, and to reduce the environmental risks.

Abstract

Changes in runoff trends have caused severe water shortages and ecological problems in agriculture and human well-being in Nigeria. Understanding the long-term (inter-annual to decadal) variations of water availability in river basins is paramount for water resources management and climate change adaptation. Climate change in Northern Nigeria could lead to change of the hydrological cycle and water availability. Moreover, the linkage between climatic changes and streamflow fluctuations is poorly documented in this area. Therefore, this study examined temporal trends in rainfall, temperature and runoff records of Kaduna River basin. Using appropriate statistical tools and participatory survey, trends in streamflow and their linkages with the climate indices were explored to determine their amplifying impacts on water availability and impacts on livelihoods downstream the basin. Analysis indicate variable rainfall trend with significant wet and dry periods. Unlike rainfall, temperature showed annual and seasonal scale statistically increasing trend. Runoff exhibit increasing tendency but only statistically significant on annual scale as investigated with Mann–Kendall trend test. Sen’s estimator values stood in agreement with Mann–Kendall test for all variables. Kendall tau and partial correlation results revealed the influence of climatic variables on runoff. Based on the survey, some of the hydrological implications and current water stress conditions of these fluctuations for the downstream inhabitants were itemized. With increasing risk of climate change and demand for water, we therefore recommend developing adaptive measures in seasonal regime of water availability and future work on modelling of the diverse hydrological characteristics of the entire basin.

Abstract

The purpose of the present study was to analyse the contents of calcium, magnesium, potassium, and sodium in bottom sediments of two water reservoirs. The chemical composition of the bottom sediments and the ratios between the studied macronutrients were assessed, taking into account the nutritional requirements of plants, to determine whether the sediments were suitable for use in natural/agricultural settings.

The study was conducted at two water reservoirs: the Brody Iłżeckie reservoir built on the Kamienna River in the Świętokrzyskie Province, and Zalew Zemborzycki, lake on the Bystrzyca River in the Lublin Province. Both bodies of water serve as flood water diversion and leisure facilities, and are also used, to a small extent, by the industry. They have a similar age and surface area. Bottom sediments were collected from the reservoirs a single time: 14 samples from Zalew Zemborzycki and 17 from Brody Iłżeckie. Samples were tested for total contents of Ca, Mg, K, and Na. The bottom sediments from Zalew Zemborzycki contained higher amounts of calcium, magnesium, and potassium than the material from Brody Iłżeckie. The values of ratios between K:Mg and K:(Ca + Mg) were similar for both reservoirs, and Ca:Mg and Ca:K were slightly more favourable for the sediments taken from Brody Iłżeckie.

Abstract

The term flooding is often associated with a stream overflow or a marine flood, runoff-floods is rarely considered, and today suffers from a lack of knowledge and control of the phenomenon. This paper, presents a geographic information system iRIP@ – Flooding by Intense Pluvial Runoff (French acronym), which is a new tool to mapping flooding by runoff as a tool for decision-making by mapping runoff flooding in Gareat El Taref catchment (Northeast Algeria), with identifying the area of production, transfer and accumulation of flood.

Us results, we have cards represent the potential of a territory to generate the various hydraulic dynamics of runoff: the runoff production card, the runoff transfer, the runoff accumulation card, the runoff-flooding card.

A visual simulation on the flood risk card indicates that the areas with an important runoff flood risk are the communes of Khenchela Oum El Bouaghi Ain El Beida and F’kirina. Moreover, the roads that join Khenchela with Ain El Beida and with Oum El Bouaghi.

Khenchela city is exposed to a great risk of flooding by runoff, the solution proposed by the authorities and that summarizes by the construction of a canal is not sufficient, because on the one hand the north of the city remains exposed to this risk. On the other hand, a large area of runoff production is located between the canal and the city.

It is probably operating to encourage farmers to introduce certain agricultural practices that are part of a sustainable management of flood risk by runoff.

Abstract

In order to ensure better availability of water resource to different users, we undertook a dependability study of system for drinking water supply. A real case study was done on the water supply network in the city of El Hadjarin Algeria. We started from the site modelling, which provided a calculation of a Hydraulic Criticality Index (HCI) in order to prioritize the importance of pipes in the network. Once the indices were calculated, a modelling procedure of reliability block diagram was applied. The objective was to study and analyse the existing network to measure the water availability problems and try to provide viable solutions. An action on the structural aspect and hardware may be required in order to ensure better availability of water and make the system more reliable. Spatial modelling is also proposed to be able to monitor different parts of the network where problems may occur.

Abstract

The effect of physical and biological qualities of wells after submergence was assessed following December 2014 flood in Kelantan. Studies were carried out on a total of 65 wells from 13 stations around Kelantan River basin in which the wells’ water were sampled for pH, total dissolved solid (TDS), turbidity and microbial contamination. About 95% of the well showed to be contaminated, 7 out of 65 samples (11.1%) showed TDS values >400 μS·cm−1; and 19 samples (29.2%) recorded turbidity beyond 7.0 NTU. Statistical non-parametric tests carried out on independent groups showed that the status of well contamination was neither determined by both degree of submergence nor by the geographical location. Also the physico-chemical parameters are independent of flood inundation. However, TDS and turbidity values changed based on geographical location, at p < 0.05. Well from estuary recorded higher TDS (241.2 μS·cm−1 ±159.5 SD) and turbidity (8.04 NTU ± 6.53 SD) compared to those from inner basin (TDS at 156.3 μS·cm−1± 88.9 SD; turbidity at 2.90 NTU ± 2.46 SD), respectively. The flood water had played significant role in the transmission of existing contaminant, and most of the wells were unsafe for drinking. We concluded that the degree of flood submergence does not necessarily determine the severity of the well contamination in Kelantan, but the existing contamination may exacerbate further the potential risk during post flood period.