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Estimation of Soil Erosion in Rodnei Mountains National Park Using G.I.S. Technique

Abstract

Erosion is one of the biggest and most widely spread forms of soil degradation, having an impact on both the surrounding environment and the economical one as well. According to a recent study from 2014-2015 by the Common Research Center an estimate of approximately 11.4% of the EU’s territory has been affected by the erosion process in moderate to high levels, the soil’s erosion rate being higher than 5t/ha/year. A significant part of Romania’s surface feels the negative effects of the soils degradation, erosion being the most widely spread long-term complex phenomena. Identifying as exactly as possible the areas with erosion risk is recommended in order to intervene with measures of consolidation, leveling, terrain modeling and other hydro-improving constructions. For this reason, for the studied area, Rodnei Mountains National Park (Maramureș County, Bistrita-Nasaud County), having a surface of 47.177 ha, the soil’s erosion has been modeled via the USLE model, developed by Motoc in 1979, taking into consideration all the climate conditions specific to Romania. Following the implementation of the G.I.S environment model, the soil’s erosion estimate values have been obtained, subsequently being divided in 8 classes of erosion, losses of soil less than 0.5t/ha/year representing 89.3% out of the park’s total surface. Researching the model’s obtained results and comparing them to existing values of soil erosion, locally and nationally, we can draw the conclusion that the results of the USLE model are truthful, and that the model can be successfully used in the studied area. Thereby, the study has targeted the determination of vulnerabilities at the erosional processes and vulnerabilities to erosion, the risk of erosion susceptibility being assessed.

Open access
The Features of the Cyclical Fluctuations, Homogeneity and Stationarity of the Average Annual Flow of the Southern Buh River Basin

Abstract

In the last decades, according to researches of scientists of the world becomes more evident that the global and regional climate changes impact on the water regime of rivers and leads to break of the stationarity of observations series. In this study we analysed the long-term (since the beginning of the observations to 2012) average annual flow of the Southern Buh River Basin (37 gauging stations) and its cyclical fluctuations during a long period of time. The methodological approaches based on the using of hydro-genetic methods for estimation the homogeneity and stationarity of hydrological series were used. We researched that series of observations are homogeneous and stationary. However, not all series of observations were representative for determination of the stable average value. The presented results illustrate that the long-term fluctuations of the average annual flow at all gauging stations is synchronous. Therefore, the climatic conditions of the flow formation are homogeneous. However, these fluctuations are not always synchronous phase. We found out that the average annual flow in this basin fluctuates and has decreasing trend in the last decade. It is due to cyclical fluctuations of the river flow. We calculated the statistical parameters for all gauging stations.

Open access
Gis-Based Determination of Landslide Properties in Regional Scale: Karabuk Province (NW Turkey)

Abstract

Natural hazards and their consequences are of great importance throughout the world. In Turkey, landslides constitute approximately 5% of the overall damage. The most important part of any landslide study is to extract landslide properties and database. In this study, Karabük city was selected as a study area which is known as one of the most landslide prone areas in Turkey. The study area contains the official borders of Karabük province. The area surrounded by the coordinates of 4518148N-4603891N and 424593E-512511E which has an areal extent of 4067 km square. The data of 1663 occurred landslides in Karabük, were digitized from 1/500.000 scale Turkey Landslide Inventory Map by considering the scarps with point vector format. Considering the literature, parameters of lithology, slope, topographical elevation, NDVI and aspect, which were frequently used among the researchers in landslide assessments, were produced and analyzed a GIS (Geographical Information System) platform. In order to perform analyses, the study area was divided into 62 watersheds. Then, lithology, slope, aspect, topographical elevation and NVDI characteristics of the region were automatically extracted by considering the landslide locations. In this type of study, GIS provides many advantages. For the next stages of landslide assessments such as susceptibility, hazard and risk, this stage provides important inputs and can be considered as the most important stage.

Open access
Improving Upstream and Downstream Fish Passage at Retis Dam on Hârtibaciu River - Sibiu County (Transylvania)

Abstract

Retis (dam Retis), hydro-technical development like many other transverse hydraulic structures cancel the longitudinal connectivity of Hârtibaciu water course, blocking the migration of different (migrating) species of fish in the river. Also, the lateral connectivity was heavily affected on this water course at a rate of 60%. Therefore, proposing engineering solutions to recover both (lateral and longitudinal) types of connectivity is vital to restore the local ecobiom. The purpose of this article is to establish longitudinal connectivity through an engineering solution that facilitates the fish migration upstream - downstream of Retis dam. This paper proposes an engineered fish passage solution for Retiș Dam on the Hârtibaciu River, using the criteria described in the Water Framework Directive 2000/60/EC document. Anthropogenic barriers located in the Hârtibaciu River disrupt and delay movement of local fish fauna including: Alburnoides bipunctatus (Bloch, 1782), Squalius cephalus (Linnaeus, 1758), Alburnus alburnus (Linnaeus, 1758), Rhodeus amarus (Bloch, 1782), Gobio gobio (Linnaeus, 1758), Romanogobio kessleri (Dybowski, 1862), Barbatula barbatula (Linnaeus, 1758), Barbus meridionalis Risso, 1827 Misgurnus fossilis (Linnaeus, 1758), Cobitis taenia Linnaeus, 1758, Cobitis romanica (Băcescu, 1943), and Cobitis aurata (De Filippi, 1863).

Open access
An Investigation Concerning the Impact of Climate Changes on the Water Equilibrium in the Egyptian Nile Delta

Abstract

In such problematic water situation in Egypt, control and saving of the available limited quantity takes great importance from both technical and national points of view. In addition to all the well-known traditional reasons of the problem such as pollution, over usage, and bad traditions of dealing with water, a new very important reason is added nowadays, called “Climate Changes” which has a direct impact on sea water rising, that causes a serious attack of the salt water to the fresh water especially in River Deltas., Not only the surface water, but also the ground water. Since that process proved some acceleration, several investigations have recently considered the worst impacts of climate change and sea water level rise on sea water intrusion. Most of them have revealed the severity of such problem, and the significance of the land movement of the dispersion zone under the sea water level rise situation. In this paper, we try to introduce a technical review and study for the most popular studies concerning our topic, and its most important conclusions, as an approach for preparing the Ph.D. thesis about the Nile Delta water equilibrium in the light of the expected Mediterranean Sea water level rise. Nile Delta, which located between Damietta Branch on the East, and Rosetta Branch on the west, occupies about 20000 square kilometers of the most rich, productive land in Egypt. About 50% of Egyptian population live in that area, agriculture is the main human activities on them, so water is the prime factor in their life, and their agriculture investments. The great amount of this investment depends on the ground water, which faces a serious challenge due to, two reasons, first, is the overuse, and over pumping, while the second is the attack of the salt water due to the Mediterranean Seawater level rise, because of the climate changes. These two reasons must be overcome, if the first reason can be controlled by law, and technical roles, the second reason needs intensive studies and investigations concerning the interaction between seawater and fresh ground water.

Open access
Landform Analysis Using Terrain Attributes. A Gis Application on the Island of Ikaria (Aegean Sea, Greece)

Abstract

The main objective of this study is to classify the landforms of Ikaria Island by conducting morphometric analysis. The whole classification process is based on the calculation of the Topographic Position Index (TPI). The delivered TPI landform classes are spatially correlated with the geology, slope, valley depth and the topographic ruggedness of the island. The results of this study indicate the presence of two distinctive landform units, affected mainly by the local geological setting.

Open access
A Landsat 8 OLI Satellite Data-Based Assessment of Spatio-Temporal Variations of Lake Sevan Phytoplankton Biomass

Abstract

The Sevan is one of the world’s largest highland lakes and the largest drinking water reservoir to the South Caucasus. An intensive drop in the level of the lake that occurred over the last decades of the 20th century has brought to eutrophication. The 2000s were marked by an increase in the level of the lake and development of fish farming. To assess possible effect of these processes on water quality, creating a state-ofthe- art water quality monitoring system is required. Traditional approaches to monitoring aquatic systems are often time-consuming, expensive and non-continuous. Thus, remote sensing technologies are crucial in quantitatively monitoring the status of water quality due to the rapidity, cyclicity, large-scale and low-cost. The aim of this work was to evaluate potential applications of the Landsat 8 Operational Land Imager (OLI) to study the spatio-temporal phytoplankton biomass changes. In this study phytoplankton biomasses are used as a water quality indicator, because phytoplankton communities are sensitive to changes in their environment and directly correlated with eutrophication. We used Landsat 8 OLI (30 m spatial resolution, May, Aug, Sep 2016) images converted to the bottom of atmosphere (BOA) reflectance by performing standard preprocessing steps (radiometric and atmospheric correction, sun glint removal etc.). The nonlinear regression model was developed using Landsat 8 (May 2016) coastal blue, blue, green, red, NIR bands, their ratios (blue/red, red/green, red/blue etc.) and in situ measurements (R2=0.7, p<0.05) performed by the Scientific Center of Zoology and Hydroecology of NAS RA in May 2016. Model was applied to the OLI images received for August and September 2016. The data obtained through the model shows that in May the quantity of phytoplankton mostly varies from 0.2 to 0.6g/m3. In August vs. May a sharp increase in the quantity of phytoplankton around 1-5 g/m3 is observable. In September, very high contents of phytoplankton are observed for almost entire surface of the lake. Preliminary collation between data generated with help of the model and in-situ measurements allows to conclude that the RS model for phytoplankton biomass estimation showed reasonable results, but further validation is necessary.

Open access
Nature and Environment in Collective Perception. Study on the Plain Countryside of the Northern Half Crisana Province, Romania

Abstract

The main objective of this study is geared toward how the public understands the nature and the environment, and relates to them. The research universe is represented by the inhabitants of the plain step in the northern half of Crisana Province (north-western Romania). It started from the idea that social representations generate attitudinal and behavioral patterns and the way in which people interact with the environment and nature has a significant influence on quality of life and social development. Therefore, the social representations about the environment and nature have direct effects on our future and can be oriented towards the active participation to the efforts to protect the environment and the nature in general. There were 671 residents of 34 villages questioned and their answers have set a certain socio-geographical pattern on the specifics of life environment belonging to plain. The life environment was perceived by us as a way of reporting to the nature and the environment. The rural respondents from the plain come up with the most common answers, even identical in content, drawing the nature and the environment as ambience, as the space around them.

Open access
Population Structure in the Ialomiţa Subcarpathians

Abstract

The analyisis of the demographic structures along with that of the main geo-demographic indicators is obligatory in any human geography study regarding a physical-geographic or administrative-territorial unit. The relation between various age groups, the dynamics of the ethnic, linguistic, or confessional structures, the variation of the socio-economic structure offers essential milestones for explaining the social, economic and cultural evolution of a region. Several specific indicators that can be calculated based on these types of structures lay at the basis of the demographic policies and of the identification of the most opportune development programs. This works aims to present a synoptic view of these aspects, of the dynamics of these indicators in the Ialomiţa Subcarpathians after the year 1990, and explain the factors that have influenced these processes and phenomena. This approach is important in the present conditions, when this zone (which holds a very diverse array of natural resources) is faced with a significant demographic and economic decline, which has determined, on the one hand, changes within these structures, and, on the other hand, implicitly, substantial changes on all the levels of the social and economic life.

Open access
Water Supply in the Republic of Serbia – State and Perspectives

Abstract

Water supply has pronounced priority, over other forms of water use. The term water supply includes the ensure of high quality water in general terms, for households, public needs and economic activities. The Republic of Serbia disposes with considerable underground and surface water resources, which are used for supplying, but it is required their rational utilization. The aim of this study is to show the current state of water supply on the territory of Serbia based on the analysis of the different indicators. One of the goal is to scan prevalent conditions and problems related to it and to propose optimal solutions. The survey includes an explanation of the long - term needs of the Republic of Serbia for fresh water (as well as share of different sources in the total water supply) and estimation of the possibility of satisfying that needs from available resources. On the base of that, there are adopted conclusions about basic directions of further development in the field of water management and water supply in Serbia.

Open access