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Mohamed Zobiri, Mohamed Mazour and Boutkhil Morsli

Abstract

Water erosion remains a major concern on the marly slopes. Where erosive processes continue to increase and continue to pose serious problems and where knowledge is still insufficient on erodibility and its evolution and on solutions to soil erosion problems. The aim of this work is to contribute to the understanding of the functioning of soils on marl substrate in relation to erosion and to evaluate the effectiveness of the anti-erosion measures used in this type of environment. The Isser watershed, where several anti-erosion techniques were used, is the subject of this study. The analysis of the anti-erosion installations shows that most of the developments have been made according to standards and have worked well. But their effectiveness is different from one technique to another. The earthen thresholds seem to be the most suitable and the most effective. The effectiveness of earthen structures is summed up in stability, durability, cost-effectiveness, sediment storage, flood plating and water storage for a significant length of time, and had a positive impact on reducing erosion and the silting rate of the dam. The gabion thresholds also have a better stability and a good seating, but they are very sensitive and can undergo damage that reduces their effectiveness with regard to erosion. Dry stone thresholds are the least desirable and are often inadequate and inefficient in this type of terrain. A purely mechanical and/or biological vision in this type of environment is however insufficient, the mechanical arrangements associated with the biological developments are more effective.

Open access

Marzieh Mokarram, Mehran Shaygan and Dinesh Sathyamoorthy

Abstract

The study of groundwater resources in relation to topography is important. Clearly, in different topography, depth of the water level is different. Therefore, the aim of this study is the determination of the relationship between landform classes with compound topographic index (CTI) and depth of the water for the Maharlou-Bakhtegan watershed, Fars Province, Iran. In order to evaluate the depth of the water for the study area, CTI and geomorphology (landforms) were derived from a Shuttle Radar Topography Mission (SRTM) digital elevation model (DEM). The results of landform classes extracted using topographic position index (TPI) showed that the largest landform is open slope, while the smallest are plains. It was found that CTI and depth of the water values are high in plain classes, while they are low in local ridges. High depth of the water were found to be mostly confined to the pit regions in the plain landform, because groundwater recharge occurs in the zones where standing water remains for sufficient long period of time and has favourable condition for recharge.

Open access

Gheorghe Jigau, Leșanu Mihai, Bîrsan Ana, Blidari Anton, Borș Natalia, Plăcintă Nina and Cernolev Elena

Abstract

The chernozems evolution of the Carpatho-Danubian-Pontic space clearly shows two consecutive phases: climatogenic and anthropo-climatogenic. The latter is characterized by increasing agrogenic impact on soil climate. The soil cover of Carpathian-Danubian-Pontic space is the hierarchical functional system long-time product. Pedogenetic factors → pedogenetic regimes → pedogenetic processes → soil (soil cover). During Pleistocene, the chernozem pathogenesis in the region resumed 13 times, each time starting from the carbonic chernozem phase. Zonal climatic cyclicality has led to the differentiation of chernozem subtypes, determined by the zonal differentiation of pedogenic regimes and typogenetic elemental processes. The current stage of chernozem cleavage in the region began 10-12 thousand years ago. The evolution of soils in the soil was determined by the climate cyclicality and the increase of anthropogenic imputations and involves the succession over time of several phases: - Cryogenic with poorly developed soil by A (AO) - C Order; - Early dynamic halocene with developed zonal soil formation; - Late halocene with climatic evolution of the profile; - Natural-anthropogenic. During the last one, four eras were accelerated: natural-anthropo-turbian, naturalanthropic modification, natural-anthropic restructuring and natural-anthropic stagnation. Increasing the anthropogenic impulses led to the modification of the climatic → soil relations in the sense of increasing the degree of continentalisation of the soil climate materialized in the aridization of the soil cover, the change of the sense and intensity of the typogenic processes and the induction of some nontypical elementary processes of the chernozemic pedogenesis.

Open access

Aabid Mohmad and Farooq Aadil

Abstract

As a conceptual framework, Sustainable Development (SD) intends to improve current Well-Being, while preserving or maintaining the basis for future Well-Being (Solow, 1991). In order to measure Sustainable Development various indicators were chosen, among which health has been considered as an important indicator. As a result, we see a huge focus on health in Sustainable Development frameworks. But, the emphasis of frameworks has been only on the physical and epidemiological factors affecting the health. In contrary, in context of a highly political turmoil zone, it is the psychological well-being that is severely affected. This component of health i.e., psychological well-being is neglected to find a significant place in Sustainable Development frameworks. Since, these frameworks are crucial for national level policy making and it is likely that policies formulated on such frameworks may not replicate the same successful results in every context (such as in Armed Conflict). With such understanding in the background, this paper will show the need to focus on mental health in armed conflict situations in Sustainable Development frameworks. This paper will attempt to show how ignoring mental health in armed conflict situations impede development. The need to develop a holistic framework which focuses on mental health in Armed Conflict situations will be highlighted in context of Kashmir.

Open access

Gheorghe Duca, Maria Nedealcov and Ivanov Ivanov

Abstract

Although it is considered that the socio-economic impact over the last decades on surface water quality is significant, the role of changing regional climate that is manifested by the intensification of desertification process is crucial. In this context, it is important to know the current trends of change in total runoff of surface of surface waters in the context of increase of desertification degree of the regional climate attested in recent years

Open access

Dumitru Mihăilă and Petruț Ionel Bistricean

Abstract

This study addresses a current issue concerning spatial and temporal analysis of Moldova's climate resources and is intended for the use of people involved in various tourism and related activities. For researchers in the field, the study will be a source of information, allowing comparison of the results obtained for other locations, and for practitioners an indispensable working tool. The motivation for the present study resides in the sparseness and ambiguity of the analysis of climate resources for tourism included in the assessment of the natural tourism potential of Romania. We aim to improve this approach by constructing for Moldova a statistically relevant, quantitative analysis of what climate offers the tourists. To achieve the proposed objectives, we used TCI and a climate database sufficiently detailed to capture climate patterns up to ten-days time intervals. We showed that in Moldova the May-September interval is the most favorable for developing all forms of tourism. We then customized the analysis at the level of each tourism resort. Our study is among the first in this region to use such analysis and provides clear research results to those involved in tourism to improve their decision-making process. The results are very important in supporting tourism in Moldova and will contribute to raising the economic potential of the region.

Open access

Witold Suchecki

Abstract

The elimination of hazards caused by cavitation phenomena is an important issue to be considered in the design of process equipment including flow machinery. These hazards are: cavitation erosion, efficiency decrease as well as vibration and noise. One of the most intensive and dangerous forms of cavitation is vortex cavitation that accompanies the operation of hydraulic machines in which components comprised of rotating blades are applied.

Velocity fields around cavitation vortices generated by the model of a propeller blade were experimentally studied in a cavitation tunnel. Flow images were recorded using a high-speed camera and processed using particle image velocimetry (PIV) complemented with computer-aided techniques that had been developed for the purpose of this research. These techniques included the removal of image distortions on the basis of a calibration mask, determination of instantaneous velocity distributions and removal of air-bubble traces from flow images.

Experimental studies result examples were presented in the form of velocity fields determined in the longitudinal plane as well as in three transverse planes remote from the blade. Instabilities of the cavitating vortex stream and of the local liquid-flow velocity in its surrounding were detected. The effect of the angle of attack of propeller blade on the instability of the vortex stream and the effect of the presence of the cavitating vortex kernel on the local velocities of the surrounding liquid, were determined.

Open access

Mexoese Nyatuame and Sampson K. Agodzo

Abstract

The forecast of rainfall and temperature is a difficult task due to their variability in time and space and also the inability to access all the parameters influencing rainfall of a region or locality. Their forecast is of relevance to agriculture and watershed management, which significantly contribute to the economy. Rainfall prediction requires mathematical modelling and simulation because of its extremely irregular and complex nature. Autoregressive integrated moving average (ARIMA) model was used to analyse annual rainfall and maximum temperature over Tordzie watershed and the forecast. Autocorrelation function (ACF) and partial autocorrelation function (PACF) were used to identify the models by aid of visual inspection. Stationarity tests were conducted using the augmented Dickey–Fuller (ADF), Mann–Kendall (MK) and Kwiatkowski–Phillips–Schmidt–Shin (KPSS) tests respectively. The chosen models were evaluated and validated using the Akaike information criterion corrected (AICC) and also Schwartz Bayesian criteria (SBC). The diagnostic analysis of the models comprised of the independence, normality, homoscedascity, PP and QQ plots of the residuals respectively. The best ARIMA model for rainfall for Kpetoe and Tordzinu were (3, 0, 3) and (3, 1, 3) with AICC values of 190.07 and 178.23. That of maximum temperature for Kpetoe and Tordzinu were (3, 1, 3) and (3, 1, 3) and the corresponding AICC values of 23.81 and 36.10. The models efficiency was checked using sum of square error (SSE), mean square error (MSE), mean absolute percent error (MAPE) and root mean square error (RMSE) respectively. The results of the various analysis indicated that the models were adequate and can aid future water planning projections.

Open access

Mariusz Szymaniak

Abstract

The paper presents modernisation of the steam turbine stage situated in front of the turbine extraction point, based on a 225 MW turbine LP stage as an example. The modernised design is intended to better control the steam flow in this area. In the presented design a special ring is used to drive the steam leakage flow directly to the heat exchanger. The performed experiments and numerical analyses confirmed measurable exploitation and efficiency advantages of the introduced modernisation. So far, it has been successfully applied in a number of turbines working in inland power plants, but its use can be easily extended, without need for further modification and without advantage loss, to marine turbines, especially those used as main propulsion in sea-going vessels.

Open access

Cristina-Alina Ficuț, Vlad Măcicășan, Cristian-Valeriu Maloș, Octavian-Liviu Muntean, Gheorghe Roşian and Tibor Hartel

Abstract

The management of pastures is very important to reduce soil erosion. A special attention is generally needed for the wood pastures which combine livestock grazing with trees and shrubs. In this paper, we investigated the differencess between the wood pastures and tree-less pastures and their role to prevent or mitigate the soil erosion. The soil erosion assessment has been performed by using of RUSLE and GIS. The model has been applied in two study-polygons with wood pasture and tree-less pasture located in the northern part of Hartibaciului Tableland (Romania). Our outcomes showed and highlighted by comparison that wood pastures have a lower predicted annual soil loss than pastures with accidental presence of trees. This fact suggests that wood pastures are more resilient to soil erosion than tree-less pasture. The metholology tried to calibrate a preliminary model of soil erosion assessment for wood pastures into the southern part of Transylvania.