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Water quality index assessment of Koudiat Medouar Reservoir, northeast Algeria using weighted arithmetic index method

Abstract

Water quality index (WQI) is a mathematical tool used to transform large quantities of water quality data into a single number which present water quality level. The aim of the present study is to evaluate the quality of Koudiat Medouar Dam in Batna (Algeria) to assess its suitability for drinking purposes. Samples were assessed for ten (10) physicochemical settings namely pH, electrical conductivity, total hardness, nitrate, sulphate, chloride, calcium, magnesium, dissolved oxygen and turbidity. The calculation of WQI was done via weighted arithmetic index method. The WQI values ranged from 99.097 to 174.92 during 2015. It reflected that the water samples were in February in the range of very poor quality and ranged to be in unsuitable for drinking rang in the all other months. The WQI of the present study reveals dam water is contaminated and not suitable for drinking purpose without giving treatment.

Open access
Spatial Variation in Blooming and Yield in an Apple Orchard, in Romania

Abstract

The aim of this study was to analyse the spatial variation of blooming, yield and quality parameters, in an apple orchard, by using precision agriculture tools. This study is a preliminary step in order to create management zones, to take the management decisions and made the evaluation of the applied practices. The study was conducted in the Research and Development Station for Pomology Voinesti, Dambovita, on the 0.9 ha orchard. The orchard consists in Florina apple trees and Generos pollinator. The surface was mapped with GPS and the yield of each tree was manually harvested and weighed. Apple quality was evaluated in terms of: firmness, soluble solid content, juice pH. Also, in spring was determined the number of flowers/tree and the exact period of flowering. The interpolated maps were created using Surfer 8 software and the correlations between yield and quality have been established; some quality characteristics are negatively correlated with yield, like firmness.

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Current role of grasslands in development of agriculture and rural areas in Poland - an example of mountain voivodships małopolskie and podkarpackie

Current role of grasslands in development of agriculture and rural areas in Poland - an example of mountain voivodships małopolskie and podkarpackie

In paper the current situation of agriculture activity in mountain areas in Poland on the example of two mountain voivodships: małopolskie and podkarpackie was presented. Particular the role of permanent grasslands in development of agriculture and rural areas was highlighted. The tools for support of agriculture development in mountain areas i.e. LFA payments, payments for cow and sheep raising were presented. The future prospects of the development of mountain areas in Poland were showed.

Open access
Impact of the forest succession on efficiency of the arable land production

Abstract

The paper presents the studies involving analysis of changes in shape of parcels of arable land under the influence of forest succession. The object of the research is the village Grębosze located in Świętokrzyskie voivodeship. The study material will cover all arable land existing in the studied village. The source of data were numerical registry maps from 1998 and 2013. The basic element of research, enabling comparison of changes in the efficiency of the production process are continuous parts of the parcels covered by one form of use. In the course of the output data processing and determination of the necessary technical parameters for the tested surface elements, the specialized tools and statistics were used. The studies were related to the evaluation of formation of these surface structures on the basis of their shape meter in the form of the so-called costs of cultivation. The obtained results make it possible to tell, to what extent the changes resulting from the consequences of the secondary forest succession influence the process of cultivation of neighbouring arable land.

Open access
Evaluation of the effects of land consolidation in the Latyczyn village in terms of land protection against erosion on the slope scale

Abstract

Soil erosion by water is an important economical issue strongly deteriorating environment and requiring remedial actions. The study was designed to evaluate antierosion effect of changes in the layout of plots from along to across slope as an effect of land consolidation. Moreover, rightness of leaving newly set out boundaries of plots without any protection (i.e. sodding) was evaluated. For this purpose simulations of use of additional anti-erosive measures were done. The Water Erosion Prediction Project (WEPP) model was used. Studies have shown that in addition to the design of transverse layout of parcels during consolidation, further antierosion measures may be necessary to reduce soil loss and sediment yield. In order to minimize soil losses outside the slope, boundaries between the newly designed fields should be sodded already in the post consolidation management. Limitation the amount of erosion over the entire slope requires use of additional protection measures in the upper part of slopes e.g. shelterbelts and antierosion crop rotations. WEPP model can be recommended for Provincial Bureaus of Surveying as a tool to support the development of assumptions for consolidation projects of lands threatened by erosion.

Open access
Assessment of the impact of climate change on the freshwater availability of Kaduna River basin, Nigeria

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.

Open access
Hydrochemical study of Drean–Annaba aquifer system (NE Algeria)

Abstract

Water quality is subject to frequent changes in the Drean-Annaba alluvium aquifer. Water-rock interaction can not be the only process that produces the observed modification, but dryness that the country knew during the last two decades has highly contributed to the water quality changes. During this period, irregularities in the distribution of rainfalls, in time and space, have been observed. As a result, a periodicity in hydrochemical changes in water of wells and rivers is noticed. Statistical, the principals components analysis (PCA) tools and Tickel diagram have been used to show, through chemical presentation, these effects. The results show, indeed, seasonal changes of water quality for the period 1999-2000. From a cationic point of view, a competition between alkaline and alkaline earths is shown. On the other hand, from an anionic point of view, there is a transition from chlorides to sulphates and may be to bicarbonates. The present work was carried out in a relatively small area and this was useful to show the relationship that existed between dryness and water quality of both the aquifer system and surface water.

Open access
Possibility of GPS precipitable water vapour for reservoir inflow forecasting

Abstract

We investigated the possibility of using GPS precipitable water vapour (GPS-PWV) for forecasting reservoir inflow. The correlations between monthly GPS-PWV and the inflow of two reservoirs were examined and the relationship tested, using a group method of data handling (GMDH) type neural network algorithm. The daily and monthly reservoir inflows were directly proportional to daily and monthly GPS-PWV trends. Peak reservoir inflow, however, shifted from the peak averages for GPS-PWV. A strong relationship between GPS-PWV and inflow was confirmed by high R 2 values, high coefficients of correlation, and acceptable mean absolute errors (MAE) of both the daily and monthly models. The Ubon Ratana reservoir model had a monthly MAE of 54.19·106 m3 and a daily MAE of 5.40·106 m3. By comparison, the Lumpow reservoir model had a monthly MAE of 25.65·106 m3 and a daily MAE of 2.62·106 m3. The models using GPS-PWV as input data responded to extreme inflow better than traditional variables such that reservoir inflow could be predicted using GPS-PWV without using actual inflow and rainfall data. GPS-PWV, thus, represents a helpful tool for regional and national water management. Further research including more reservoirs is needed to confirm this preliminary finding.

Open access
Free surface profile and inception point as characteristics of aerated flow over stepped spillway: Numerical study

Abstract

Stepped spillway is hydraulic structure designed to dissipate the excess in kinetic energy at the downstream of dams and can reduce the size of stilling basin at the toe of the spillway or chute. The flow on a stepped spillway is characterised by the large aeration that can prevent or reduce the cavitation damage. The air entrainment starts where the boundary layer attains the free surface of flow; this point is called “point of inception”. Within this work the inception point is determined by using software Ansys Fluent where the volume of fluid (VOF) model is used as a tool to track the free surface thereby the turbulence closure is derived in the kε turbulence standard model. This research aims to find new formulas for describe the variation of water depth at step edge and the positions of the inception point, at the same time the contour map of velocity, turbulent kinetic energy and strain rate are presented. The found numerical results agree well with experimental results like the values of computed and measured water depth at the inception point and the numerical and experimental inception point locations. Also, the dimensionless water depth profile obtained by numerical method agrees well with that of measurement. This study confirmed that the Ansys Fluent is a robust software for simulating air entrainment and exploring more characteristics of flow over stepped spillways.

Open access
Evolution of the flow of drainage waters in the Oued Righ canal, Algeria

Abstract

The channel of the Oued Righ valley plays an important role in draining the drainage waters of the palm groves of 47 oases. This article evaluates and offers a simple relationship calculation of flow of drainage water carried by the channel of Oued Righ. Several work missions were carried out in the Oued Righ Valley during the period: 2010–2018. Investigations and surveys were conducted among the local population. Data and information were collected from the National Hydric Resources Agency (Fr. Agence Nationale des Ressources Hydrauliques) of Touggourt (capital of the Oued Righ Valley). Samples of bottom material and flow velocity measurements were performed at 10 gauging stations located along the canal with a length of 130 km. A simple formula for evaluating the flow rate in the channel has been highlighted. It is a practical quantification tool that will be useful for channel managers. Calculated rate exceeded 5 m3∙s−1 of wastewater and drainage flow into the nature 10 km before reaching the Chott Merouane; the place of discharge.

Open access