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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
151

Διερεύνηση των τεχνικογεωλογικών συνθηκών στο Νομό Αχαΐας σχετικά με την αναζήτηση αδρανών υλικών για διάφορες χρήσεις / Research of the engineering geological conditions of Achaia prefecture in order to find materials suitable for aggregates

Σπυρόπουλος, Ανδρέας 22 June 2007 (has links)
Σκοπός της διατριβής είναι η διερεύνηση των τεχνικογεωλογικών συνθηκών στο Νομό Αχαΐας σχετικά με την αναζήτηση αδρανών υλικών για διάφορες χρήσεις. Εξετάζονται οι γενικές, γεωμετρικές, φυσικές και μηχανικές ιδιότητες των χαλαρών αποθέσεων του Νομού οι οποίες βρίσκονται σε αφθονία στην περιοχή και μπορούν να αποτελέσουν φυσικά κοιτάσματα απόληψης αδρανών υλικών χαμηλής ποιότητας και των ασβεστολιθικών σχηματισμών που χρησιμοποιούνται κατά βάση για την παραγωγή θραυστών αδρανών. Δημιουργήθηκε βάση δεδομένων με τη βοήθεια των Γεωγραφικών Συστημάτων Πληροφοριών όπου αποτυπώνονται σε χάρτες οι περιοχές που πληρούν τα κριτήρια για να χρησιμοποιηθούν ως πηγές λήψης αδρανών υλικών με στόχο την ορθολογική διαχείριση. Τα κυριότερα προβλήματα που παρουσιάζουν οι χαλαρές αδρομερείς αποθέσεις που εξετάστηκαν είναι το μεγάλο ποσοστό παιπάλης σε πολλές περιοχές καθώς και η παρουσία κερατολιθικού υλικού που φτάνει σε ποσοστό μέχρι και 23%. / In this thesis the engineering geological conditions in Achaia prefecture are examined, in order to find materials suitable for aggregates. The general, geometrical, physical and mechanical parameters of the sand and gravel deposits examined as they are in abundance in the wider area in order to locate areas suitable for the quarrying of low quality aggregates. Moreover limestone representative samples were examined as crushed stone aggregates. Issues such as location, abundance, type and quality and general characteristics of aggregate addressed using GIS technology, while because statutory regulations, technological capabilities and available funding change with time, the maps are designed to provide a resource data base that will be useful over the years. The main problems of the examined deposits are the localy high percentage of filler which deminish the results of the sand equivalent and the quite high percentage of chert content which deminish their density and increase their soundness.
152

Compressibility Of Various Coarse-grained Fill Materials In Dry And Wet Loading Conditions In Oedometer Test

Kayahan, Ahmet 01 January 2003 (has links) (PDF)
The use of coarse-grained fill materials has grown significantly in recent years especially on account of their use in dams and transportation networks. This study investigates compressibility of various coarse-grained fill materials in dry and wet loading conditions in oedometer test. Four materials were used in the experiments, which falls into GP, GW, GM and GC categories respectively. GP material is a weathered rock obtained from Eymir Lake region. This material was chosen especially to be able to investigate degradation and particle breakage due to compaction and compression. GW, GM and GC materials were obtained by using the material called &lsquo / bypass&rsquo / which is a fill material used in the construction of metro of Eryaman. Using these four materials, large-scale double oedometer tests were carried out to investigate compressibility in both dry and wet conditions. The double oedometer testing technique is used to investigate the effect of soaking on compressibility behaviour of compacted fill materials. Various compactive efforts were used in the compaction stage to investigate the effect of compactive effort on compressibility and degradation of the four gravelly materials. Gradations of the post-test samples were obtained and particle breakage due to compaction using various compactive efforts and particle breakage due to compression were determined. It is found that amount of compression does not necessarily depend on the dry density of the material and fine fraction is also a dominating property regarding the compressibility in coarse-grained fill materials. The vertical strains induced by soaking are on the order of 12% - 20% of the compression measured in dry loading case for the well-graded coarse-grained fill materials tested. Besides, there is significant particle breakage in the compaction process and no further particle breakage in the oedometer test for GP material.
153

Avalia??o do efeito da adi??o de res?duo de borracha de pneu e brita calc?ria na formula??o de comp?sitos ciment?ceos

Silva Junior, Francisco Alves da 30 May 2014 (has links)
Made available in DSpace on 2014-12-17T14:07:22Z (GMT). No. of bitstreams: 1 FranciscoASJ_TESE.pdf: 8792658 bytes, checksum: 82015e9b1bc788b7c608317086cdc276 (MD5) Previous issue date: 2014-05-30 / Researches have shown that the introduction of rubber in concrete improves the features of its deformability, as well as contributes to environmental disposal of waste generated in the tire retreading process. Furthermore, there is a high availability of limestone within RN and CE country. Ignorance about this stone, does not allow its wide use as aggregate, leaving, this abundant supply idle. A composite of limestone gravel, with proportions of tire rubber waste which could be used as concrete would be an alternative to concrete for low applications. Therefore, this research aims to evaluate the characteristics of concrete containing limestone gravel and proportions of little aggregate replacement (sand) by tire rubber waste. To this goal, the material components of the concrete were characterized, concrete specimens with limestone gravel were made, from the dash 1.0: 2.5: 3.5, varying the water/cement ratio, and inserting a commercial plasticizer, without a proportion of residue, known as reference. From this, concrete with and without the presence of the additive in the same proportions were chosen, as well as these with the use of granite gravel, for being the most used. Selected the references, to these, replacements of little aggregate (sand) were added replaced by rubber waste from the tire retreading process, treated with 1M NaOH in proportions from 5.0 to 20.0 % by mass, cured and exposed to the semiarid environment. The results indicate the possibility of using limestone gravel in the concrete composition with workability correction using plasticizer. There was a decrease in the mechanical properties of the concrete with increments of waste rubber, but there is an improvement in toughness and deformability of the composite, which makes it interesting for the construction of non-structural concrete floors, as well as, the rubber waste delayed the hardening process, continuing to gain resistance after 28 days / Pesquisas t?m mostrado que a introdu??o de borracha no concreto melhoram as caracter?sticas de deformabilidade deste, assim como, contribuem para destina??o ambiental de res?duos gerados no processo de recauchutagem de pneus. Somado a isto, existe uma alta disponibilidade de rocha calc?ria no interior do RN e do CE. O n?o conhecimento desta pedra, n?o possibilita sua ampla utiliza??o como agregado, deixando, esta farta oferta ociosa. Um comp?sito de brita do tipo calc?ria, com propor??es de res?duo de borracha de pneu que pudesse ser utilizado como concreto seria uma alternativa para concretos destinados a baixas solicita??es. Logo, este trabalho possui como objetivo a avalia??o das carater?sticas de concretos contendo brita calc?ria e propor??es de substitui??o do agregado mi?do (areia) por res?duo de borracha de pneus. Para tanto, caracterizou-se os materiais componentes do concreto, confeccionou-se corpos de prova de concretos com brita calc?ria, a partir do tra?o 1,0: 2,5: 3,5, variando-se a rela??o ?gua/cimento, e inserindo-se um plastificante comercial, sem a propor??o de res?duo, chamados de refer?ncia. A partir deste, foram escolhidos nas mesmas propor??es concretos com e sem a presen?a do aditivo, assim como, estes com a utiliza??o da brita gran?tica, por ser a mais utilizada. Escolhidas as refer?ncias, a estas foram acrescidas substitui??es de parte do agregado mi?do (areia) por res?duo de borracha de pneu proveniente do processo de recauchutagem, tratados com NaOH 1 M, nas propor??es de 5,0 a 20,0 % em massa, curados e expostos ao ambiente semi?rido. Os resultados indicam a possibilidade de utiliza??o da brita calc?ria na composi??o do concreto com corre??o da trabalhabilidade utilizando-se plastificante. Observou-se uma diminui??o nas propriedades mec?nicas dos concretos com incrementos de res?duo de borracha, por?m existe uma melhora de tenacidade, e deformabilidade do comp?sito, o que o torna interessante para a constru??o de pisos de concretos n?o estruturais, assim como, o res?duo retardou o processo de endurecimento, continuando o concreto a ganhar resist?ncia, ap?s os 28 dias
154

COLETOR SOLAR PARA PRÉ-AQUECIMENTO DO AR EM SISTEMAS DE SECAGEM ESTUDO DE CASO CURA DO TABACO / SOLAR COLLECTOR FOR AIR PRE-HEATING ON DRYING SYSTEMS CASE STUDY - CURING TOBACCO

Schuck, Martha Lisa Rodrigo 26 April 2012 (has links)
In a country like Brazil, which has a high incidence of solar radiation, the use of solar energy is an alternative that has been researched and used with many advantages. This paper presents the design, construction and evaluation of the efficiency of a flat solar collector for pre-heating the air, executed with low cost materials, to be used in drying systems. The prototype of the solar collector with gravel bed was built to be made a survey of data from temperature and relative humidity, using a recording apparatus (data loggers), and carried out the calculations for determining the useful heat provided by the collector. Since in the state of Rio Grande do Sul there are approximately 85,560 farms growing tobacco, accounting to around 91,420 curing barns, for which the widest energy source is firewood, as a case study was proposed to use this solar collector to be used as a supplementary source of heat to the existing curing barns. A case study was conducted on the curing process, verifying the wood consumption needed for each phase of the process in order to determine its energy demands. It was observed that the application of a 3sqm surface collector represented a reduction of around 5.2% in firewood consumption, which demonstrated the economic viability of the system with a time of payback of 3.4 years. / Em um país como o Brasil, que possui alta incidência de radiação solar, o uso de energia solar é uma alternativa que vem sendo pesquisada e utilizada com muitas vantagens. O presente trabalho apresenta o projeto, a construção e a avaliação da eficiência de um coletor solar plano para pré-aquecimento do ar, executado com materiais de baixo custo, a ser utilizado em sistemas de secagem. O protótipo do coletor solar com leito de britas foi construido para que fossem feitos os levantamentos dos dados de temperatura e umidade relativa do ar, utilizando-se aparelhos registradores (data loggers), e efetuaram-se os cálculos para a determinação do calor útil fornecido pelo coletor. Sendo que no Rio Grande do Sul existem aproximadamente 85.560 propriedades produtoras de tabaco, que totalizam cerca de 91.420 estufas de cura, nas quais a fonte de energia mais utilizada é a lenha, como estudo de caso foi proposta a utilização deste coletor solar como sistema suplementar como aquecimento do ar no processo de cura do tabaco em estufas a lenha existentes. Um processo de cura foi acompanhado para verificação do consumo de lenha necessário para cada fase deste, para que fosse possível determinar a sua demanda energética. Observou-se que a utilização do coletor com 3m2 de área proporcionou a redução de 5,2% no consumo de lenha, o que demonstrou a viabilidade econômica da utilização do sistema com tempo de retorno do investimento de 3,4 anos.
155

Estudo geoarquiológico dos níveis arenoso e de cascalheira cimentada por concreção carbonática do Sítio Lagoa Uri de Cima, Salgueiro-PE.

MACEDO, Andréia Oliveira 04 March 2016 (has links)
Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2016-10-14T13:19:47Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) DISSERTAÇÃO ANDRÉIA MACEDO.pdf: 14642972 bytes, checksum: 83c5e27682e0c794cdc2fdfbc0065ad7 (MD5) / Made available in DSpace on 2016-10-14T13:19:47Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) DISSERTAÇÃO ANDRÉIA MACEDO.pdf: 14642972 bytes, checksum: 83c5e27682e0c794cdc2fdfbc0065ad7 (MD5) Previous issue date: 2016-04-04 / CAPES / A presente pesquisa constitui uma investigação geoarqueológica sobre a Lagoa Uri de Cima, localizada no município de Salgueiro-PE, abordando três escalas de análise: a escala macro, representada pelo ambiente da Lagoa, a escala meso, pela sequência estratigrafia dos sedimentos que preencheram a Lagoa, com cronologias LOE de 34.600±690 anos AP até 3.500±360 anos AP e a escala micro formada especificamente pelos dois níveis mais profundos da Lagoa, o de cascalheira cimentada por concreção carbonática, que constitui um calcrete e, pelo nível arenoso sobreposto a cascalheira. O nível de cascalheira foi estudado de forma amostral, através de microescavações de detalhe associadas às análises tafonômicas, granulométricas, de difratometria e fluorescência de raios X, datação por C-14 e isótopos do carbono da matéria orgânica do solo, enquanto para o nível arenoso foram realizadas análises granulométricas e a difratometria de raios X. Os resultados das análises do presente estudo, integrados aos dados de pesquisas anteriores, permitiram contextualizar os vestígios arqueológicos e paleontológicos encontrados nos níveis mais antigos da Lagoa, verificar os tipos de fossilização, demonstrar a coexistência dos grupos humanos com a paleofauna, há pelos menos 18 mil anos AP no Nordeste do Brasil e obter dados sobre o processo de instalação de um clima semiárido na região. / This research is a geoarchaeologycal study about Lagoa Uri de Cima, situated in Salgueiro county, state of Pernambuco. The methodological approach was built through three scales of analysis: the macro scale, represented by the lagoon environment, the meso scale composed by the stratigraphy sequence of the sediments that filled the pond, with ages since 34,600 ± 690 years BP until 3500 ± 360 years BP and, the micro scale formed specifically by the two deepest layers of the lagoon, the gravel layer cemented by carbonate concretion, which formed a calcrete and the sandy layer deposited above the gravel. The gravel layer was studied through the microdetailed excavation in laboratory of the concretion samples associated with taphonomical analysis, granolometric analysis of the sediments, diffraction and fluorescence of X- rays, C-14 dating and carbon isotopes of the soil organic material analysis, while for the sandy layer were conducted granolometric analysis of the sediments and the diffraction and fluorescence of X- rays. The results of this studies were integrated with previous survey data, that allowed contextualize the archaeological and paleontological remains that were found in the earliest sediments layers of the pond and also know the fossilization process, demonstrate coexistence between the human groups with paleofauna, at least 18,000 years BP and obtain data about the process of semi-arid climate installation in the region northeastern of Brazil.
156

Morphodynamique des bancs alternés d'une rivière de montagne aménagée / Alternate-Bar morphodynamics in an engineered mountains river

Jaballah, Mohamed 28 November 2013 (has links)
Ce travail porte sur la morphodynamique des bancs de galets alternés dans une rivière de montagne aménagée. Le site expérimental est un tronçon long de 8 km de la rivière Arc située dans les Alpes françaises. Une analyse des cartes historiques, des photos aériennes et des relevés topographiques montre que le lit de la rivière a évolué d’un style en tresse vers un lit rectiligne avec des bancs alternés contraints entre deux digues. Au milieu des années 1990, le lit de la rivière a été aplani pour former des profils trapézoïdaux. Cependant, les bancs alternés ont réapparu en moins de dixans. Une analyse des facteurs contrôlant leur formation est fournie. Les observations de terrain et l’analyse numérique 1D suggèrent que le motif de bancs alternés représente un état de quasi équilibre du tronçon. D’autre part, la topographie d’un sous-tronçon incluant un banc de galets aété mesurée 18 fois entre 2006 et 2012. Une méthodologie de construction des MNT basée sur leslignes directrices et incluant une estimation de l’erreur a été proposée pour une application aux litsde rivières. La technique de différenciation des MNT a été utilisée pour détecter les changements morphologiques du banc. Ainsi, la morphodynamique du sous-tronçon a été étudiée en la reliant aux principaux processus qui la contrôlent tels que l’hydrologie, les formes des hydrogrammes, la répartition des contraintes de cisaillement, les apports amont en sédiments et l’énergie du coursd’eau. La forme des hydrogrammes de crue ainsi que les apports en sédiments semblent être lesprincipaux facteurs influençant le bilan sédimentaire sur le site étudié. En outre, des modélisationsnumériques 2D hydro-sédimentaires ont été utilisées pour appréhender la dynamique du banc. Lessimulations ont révélé l’importance de l’interaction entre les sédiments fins et les galets sur ladynamique globale du banc. / The current research investigates the morphodynamics of gravel alternate bars in an engineeredmountainous river. The experimental site corresponds to an 8 km long reach of the Arc River, in the French Alps. An analysis of historical maps and recent aerial photographs and topographic campaigns shows that the original braided river bed has evolved to a straight bed with alternate bar system constrained within two embankments following two centuries of man-made engineeringprojects. In the mid 1990s the river bed was flattened to fit a trapezoidal cross-sectional design. However, alternate bars re-appeared in less than ten years. An analysis of the controlling factors of bar formation and evolution is provided. Field observation and 1D numerical analysis suggest that the alternate-bar pattern represents a quasi-equilibrium state of the river bed. A singlegravel bar within the reach was monitored 18 times from 2006 to 2012. A methodology of DTM construction based on breaklines is proposed for river beds and an error estimation is presented. DTM differencing technique was used to detect morphologic changes of the gravel bar. Therefore, the gravel bar and main channel dynamics were analyzed relative to main controlling processes suchas extreme hydrologic events, sediment supply, hydrograph shape, bed shear stress distribution andriver energy. Sediment supply and hydrograph shape appeared to be the main factors influencing the study site sediment budget. Moreover, 2D numerical modelling of water flow and sediment transport was performed. Sensitivity analysis was conducted to yield results in agreement with observations. Simulations revealed the relevance of the interaction between fine sediments and gravels on the bar dynamics.
157

The influence of run-off from road networks on aquatic macro-invertebrates in Mamatole commercial tree plantation (Komatiland Forests), Upper Letsitele Catchment, Limpopo Province, South Africa

Diedericks, Gerhardus Johannes 21 August 2012 (has links)
M.Sc. / The purpose of this study was to determine whether unpaved roads in commercial forests have a detrimental impact on aquatic macro-invertebrates in the receiving rivers associated with these roads. The upper section of the headwaters of the Motlhaka-Semeetse River was chosen as the Study Area because a portion is situated in the Wolkberg Wilderness area (natural area with no roads) and a portion in a commercial forestry plantation (high road network density). Stream conditions based on a rapid bio-assessment of aquatic macro-invertebrates using SASS5 were then compared between the two catchments amid 2002 and 2010. In order to support the SASS5 results, daily rainfall data from December 1959 to October 2010 was collated and compared to daily stream flow data from January 1960 to October 2010. In addition, geomorphological and instream habitat changes in the river between the two catchment areas were recorded, as well as the condition of stream crossings and their linkage to stream networks in the afforested catchment. The SASS5 results revealed that stream conditions at the upper unimpaired site were significantly better, visibly and statistically (p < 0.05) than conditions at the lower site within the forestry plantation. In addition, there were noteworthy changes in the catchment hydrology, the geomorphology and instream habitat between the natural and afforested catchments. Road network densities in commercial forests are mostly considerably higher than suggested in literature and exceed stream network densities. Roads increase the surface area for interception of rainfall and the runoff from this high density of roads results in modification of the catchment hydrology, geomorphology and instream habitat of receiving streams. This physical change to the receiving streams is one of the main reasons for the deterioration in SASS5 results, disproving the hypothesis that road networks in forestry areas have no impact on receiving aquatic ecosystems. Commercial forestry in South Africa needs to improve their road planning, layout, management and maintenance to reduce these environmental impacts. In doing so, the road network density will be reduced with considerable environmental and economic benefits.
158

Ekologija i konzervaciona vrednost vodene vegetacije šljunkara u plavnom području reke Drine / Ecology and conservation value of aquatic vegetation of gravel pit lakes in the Drina Riverfloodplain

Damnjanovic Bojan 03 December 2019 (has links)
<p>Sa&nbsp; jedne&nbsp; strane&nbsp; se&nbsp; eksploatacija&nbsp; &scaron;ljunka&nbsp; navodi kao&nbsp; značajan&nbsp; ugrožavajući&nbsp; faktor&nbsp; sa&nbsp; velikim negativnim&nbsp; uticajem&nbsp; na&nbsp; vodena&nbsp; stani&scaron;ta&nbsp; i biodiverzitet,&nbsp; dok&nbsp; same&nbsp; &scaron;ljunkare&nbsp; mogu predstavljati&nbsp; vredne&nbsp; refugijume&nbsp; akavtičnog&nbsp; biodiverziteta.&nbsp; Osnovni&nbsp; cilj&nbsp; disertacije&nbsp; je određivanje&nbsp; najznačajnijih&nbsp; i&nbsp; relevantnih hidromorfolo&scaron;kih&nbsp; parametara&nbsp; koji&nbsp; utiču&nbsp; na strukturiranje&nbsp; makrofitskih&nbsp; zajednica&nbsp; u &scaron;ljunkarama&nbsp; duž&nbsp; plavnog&nbsp; područja&nbsp; reke&nbsp; Drine&nbsp; i određivanje&nbsp; korelacije&nbsp; između&nbsp; izdvojenih parametara&nbsp; i&nbsp; kvantitativnih&nbsp; indeksa&nbsp; makrofita.Istraživanje&nbsp; je&nbsp; vr&scaron;eno&nbsp; u&nbsp; toku&nbsp; letnjih&nbsp; meseci 2015, 2016, 2017 i 2018. godine na 18 &scaron;ljunkara (60 istraživačkih vegetacijskih sektora) u okviru tri&nbsp;&nbsp; eksploataciona&nbsp; polja&nbsp; u&nbsp; Crnoj&nbsp; Bari, Badovincima&nbsp; i&nbsp; Lipničkom&nbsp; &Scaron;oru&nbsp; i&nbsp; na&nbsp; četiri prirodna&nbsp; fluvijalna&nbsp; jezera&nbsp; (13&nbsp; istraživačkih vegetacijskih&nbsp; sektora)&nbsp; u&nbsp; plavnom&nbsp; području&nbsp; reke Drine.&nbsp; Makrofitska&nbsp; vegetacija&nbsp; je&nbsp; konstatovana na svih 18 istraţivanih &scaron;ljunkara, prikupljenih na tri eksploataciona polja (Badovinci, Crna Bara&nbsp; i<br />Lipniĉki &Scaron;or). Zabeležena je 31 biljna vrsta. Kao najučestalije,&nbsp; sa&nbsp; najvećom&nbsp; apsolutnom pokrovno&scaron;ću izdvojile su se vrste:&nbsp;<em> Potamogeton nodosus</em>&nbsp; Poiret,&nbsp; <em>Ceratophyllum&nbsp; demersum&nbsp; L subsp.&nbsp; demersum,&nbsp; Myriophyllum&nbsp; spicatum&nbsp; L,Najas&nbsp; marina&nbsp; L&nbsp; i&nbsp;&nbsp; Chara&nbsp; globularis&nbsp; Thuill&nbsp;</em> Na četiri prirodna fluvijalna jezera zabeleženo je 13 vrsta.&nbsp; Vrste&nbsp; <em>Vallisneria&nbsp; spiralis&nbsp; L,&nbsp; Elodea canadensis&nbsp; Michx,&nbsp; Callitriche&nbsp; palustris&nbsp; L, Potamogeton&nbsp; natans&nbsp; L&nbsp; i&nbsp; Nuphar&nbsp; lutea&nbsp; (L)&nbsp;</em> Sm izdvojile&nbsp; su&nbsp; se&nbsp; kao&nbsp; konstantne&nbsp; i&nbsp; dominantne. Vrednosti svih kvantitativnih indeksa makrofita,<br />značajno&nbsp; su&nbsp; veće&nbsp; za&nbsp; &scaron;ljunkare&nbsp; u&nbsp; poređenju&nbsp; sa prirodnim&nbsp; fluvijalnim&nbsp; jezerima&nbsp; na&nbsp; nivouLEAFPACS&nbsp; sektora.&nbsp; Na&nbsp; istraživanim &scaron;ljunkarama,&nbsp; analizom&nbsp; klasterovanja&nbsp; je<br />izdvojeno&nbsp; 13&nbsp; vegetacijskih&nbsp; grupa&nbsp; (VG):&nbsp; VG1<em> Ceratophyllum&nbsp; demersum</em>,&nbsp; VG2&nbsp; <em>Ceratophyllum demersum&nbsp; -&nbsp; Valisneria&nbsp; spiralis</em>,&nbsp; VG3&nbsp; <em>Chara contraria,</em>&nbsp; VG4&nbsp; <em>Chara</em>&nbsp; <em>globularis,</em>&nbsp; VG5&nbsp; <em>Elodea canadensis,</em>&nbsp; VG6&nbsp; <em>Elodea&nbsp; nuttallii</em>,&nbsp; VG7&nbsp; <em>Najas marina</em>,&nbsp; VG8&nbsp; <em>Najas&nbsp; minor,</em>&nbsp; VG9&nbsp; <em>Nitellopsis obtusa</em>,&nbsp; VG10&nbsp;<em> Nuphar&nbsp; lutea</em>,&nbsp; VG11 <em>Potamogeton&nbsp; nodosus</em>,&nbsp; VG12&nbsp;<em> Potamogeton natans&nbsp;</em> i&nbsp;&nbsp; VG13&nbsp; <em>Potamogeton&nbsp; pectinatus</em>.&nbsp; Na prirodnim&nbsp; fluvijalnim&nbsp; jezerima&nbsp; konstatovane&nbsp; su četiri&nbsp; vegetacijske&nbsp; grupe:&nbsp; VG5&nbsp;<em> Elodea canadensis</em>,&nbsp; VG10&nbsp; <em>Nuphar&nbsp; lutea,</em>&nbsp; VG12<em> Potamogeton natans&nbsp;</em> i&nbsp; VG14&nbsp; <em>Typha latifolia</em>.&nbsp; Na osnovu izmerenih fizičko-hemijskih parametara,kvalitet vode u većini &scaron;ljunkara odgovara II klasi kvaliteta, na osnovu čega se mogu okarakterisati kao&nbsp; vodna&nbsp; tela&nbsp; sa&nbsp; dobrim&nbsp; i&nbsp; boljim&nbsp; ekolo&scaron;kim potencijalom. Sve &scaron;ljunkare i fluvijalna jezera se klasifikuju&nbsp; kao&nbsp; visoko&nbsp; alkalna.&nbsp; Kvalitet&nbsp; vode&nbsp; u prirodnim&nbsp; fluvijalnim&nbsp; jezerima&nbsp; odgovara&nbsp; III&nbsp; &ndash; IV&nbsp; klasi&nbsp; kvaliteta&nbsp; voda,&nbsp; pri&nbsp; čemu&nbsp; se&nbsp; mogu okarakterisati&nbsp; kao&nbsp; vodna&nbsp; tela&nbsp; sa&nbsp; slabim&nbsp; do umerenim&nbsp; ekolo&scaron;kim&nbsp; statusom.&nbsp; Značajno&nbsp; veće<br />vrednosti&nbsp; ukupnih&nbsp; suspendovanih&nbsp; materija, hemijske&nbsp; i&nbsp; biolo&scaron;ke&nbsp; potro&scaron;nje&nbsp; kiseonika, ukupnog&nbsp; organskog&nbsp; kiseonika&nbsp; i&nbsp; nitrata zabeležene su na prirodnim fluvijalnim jezerima u poređenju sa &scaron;ljunkarama. Izmerene vrednosti fizičko-hemijskih&nbsp; parametara&nbsp; ukazuju&nbsp; na mezotrofni&nbsp; karakter&nbsp; lokaliteta&nbsp; u&nbsp; Badovincima&nbsp; i mezo-eutrofni&nbsp; karakter&nbsp; lokaliteta&nbsp; u&nbsp; Lipničkom &Scaron;oru,&nbsp; dok&nbsp; se&nbsp; &scaron;ljunkare&nbsp; na&nbsp; teritoriji&nbsp; Crne&nbsp; Bare mogu&nbsp; okarakterisati&nbsp; kao&nbsp; eutrofna&nbsp; jezera.Vrednosti&nbsp; LHMS&nbsp; (modifikacionog)&nbsp; skora&nbsp; za &scaron;ljunkare kretale su se u rasponu od 9&nbsp; &ndash;&nbsp; 15, dok su vrednosti LHQA skora (stani&scaron;nog diverziteta) bile u rasponu izmeĊu 33&nbsp; &ndash;&nbsp; 44. Sliĉne vrednosti za&nbsp; LHQA&nbsp; skor&nbsp; su&nbsp; izraĉunate&nbsp; i&nbsp; za&nbsp; prirodna fluvijalna&nbsp; jezera&nbsp; (36&nbsp; &ndash;&nbsp; 49).&nbsp; MeĊutim,&nbsp; vrednosti<br />LHMS&nbsp; skora&nbsp; za&nbsp; prirodna&nbsp; fluvijalna&nbsp; jezera&nbsp; su znaĉajno&nbsp; veće&nbsp; u&nbsp; odnosu&nbsp; na&nbsp; vrednosti&nbsp; LHMS skora za &scaron;ljunkare. Ovi podaci ukazuju na manje prisustvo&nbsp; antropogenog&nbsp; pritiska&nbsp; na&nbsp; &scaron;ljunkarama u poređenju sa prirodnim fluvijalnim jezerima uistraţivanom&nbsp; podruĉju.&nbsp; Fizičko -hemijski&nbsp; i hidromorfolo&scaron;ki&nbsp; parametri&nbsp; zajedno&nbsp; su&nbsp; objasnili 57.07&nbsp; %&nbsp; od&nbsp; ukupne&nbsp; varijanse&nbsp; vegetacijskih podataka,&nbsp; sa&nbsp; 16.57&nbsp; %&nbsp; deljenog&nbsp; efekta.&nbsp; Fizičkohemijski&nbsp; parametri&nbsp; kvaliteta&nbsp; vode&nbsp; objasnili&nbsp; su 17.02&nbsp; %&nbsp; varijabilnosti&nbsp; u&nbsp; strukturi&nbsp; makrofitske vegetacije.&nbsp; Kao&nbsp; najsignifikantniji&nbsp; parametri<br />izdvojili&nbsp; su&nbsp; se:&nbsp; saturacija&nbsp; vode&nbsp; kiseonikom,ukupni&nbsp; organski&nbsp; ugljenik,&nbsp; povr&scaron;inski&nbsp; aktivne materije, temperatura, elektroprovodljivost, pH i ukpni&nbsp; alkalitet.&nbsp; Hidromorfolo&scaron;ki&nbsp; parametri&nbsp; su objasnili&nbsp; 23.48&nbsp; %&nbsp; varijabilnosti&nbsp; u&nbsp; strukturi makrofitske&nbsp; vegetacije.&nbsp; Kao&nbsp; najsignifikantnije varijable,&nbsp; izdvojile&nbsp; su&nbsp; se:&nbsp; struktura&nbsp; vegetacije&nbsp; u priobalnoj&nbsp; zoni,&nbsp; diverzitet&nbsp; prirodnih&nbsp; tipova stani&scaron;ta&nbsp; priobalne&nbsp; zone,&nbsp; prirodnost&nbsp; obale, diverzitet&nbsp; prirodnog&nbsp; supstrata&nbsp; litorala,masimalna dubina &scaron;ljunkara, povr&scaron;ina &scaron;ljunkara,indeks relativne dubine, udaljenost &scaron;ljunkara od glavnog&nbsp; reĉnog&nbsp; toka&nbsp; i&nbsp; starost&nbsp; &scaron;ljunkara. Hidrolo&scaron;ki&nbsp; parametri&nbsp; su&nbsp; objasnili&nbsp; 8.38&nbsp; % varijabilnosti u strukturi&nbsp; makrofitske vegetacije. Kao&nbsp; najsignifikantnije&nbsp; varijable,&nbsp; izdvojile&nbsp; su&nbsp; se broj plavnih talasa u vegetacionoj sezoni tokom godine u kojoj je vr&scaron;eno uzorkovanje vegetacije i broj plavnih talasa u prolećnom periodu za sve četiri&nbsp; godine.&nbsp; Ovi&nbsp; rezultati&nbsp; potvrđuju&nbsp; direktni destruktivni&nbsp; uticaj&nbsp; plavnih&nbsp; talasa&nbsp; na&nbsp; vodenu vegetaciju u vegetacionoj sezoni, kao i indirektni uticaj prolećnih poplava, usled uticaja na trofički status&nbsp; vode.&nbsp; Sumarno,&nbsp; &scaron;ljunkare&nbsp; u&nbsp; plavnom području&nbsp; reke&nbsp; Drine&nbsp; predstavljaju&nbsp; optimalno stani&scaron;te&nbsp; za&nbsp; razvoj&nbsp; retke&nbsp; i&nbsp; ugroţene&nbsp; makrofitske flore.&nbsp; Od&nbsp; ukupnog&nbsp; broja&nbsp; zabeleženih&nbsp; vrsta makrofita,&nbsp; 30&nbsp; %&nbsp; se&nbsp; kategori&scaron;e&nbsp; kao&nbsp; za&scaron;tićeno&nbsp; ili ugroženo na nacionalnom nivou.&nbsp; Značajno veće vrednosti&nbsp; konzervacionih&nbsp; indeksa&nbsp; ustanovljene su&nbsp; za&nbsp; &scaron;ljunkare&nbsp; u&nbsp; poređenju&nbsp; sa&nbsp; prirodnim fluvijalnim jezerima, &scaron;to ukazuje na njihov visok ekolo&scaron;ki&nbsp; potencijal.&nbsp; Ustanovljen&nbsp; je&nbsp; visok diverzitet&nbsp; prioritetnih&nbsp; tipova&nbsp; akvatiĉnih&nbsp; stani&scaron;ta prema&nbsp; Pravilniku&nbsp; o&nbsp; kriterijumima&nbsp; za&nbsp; izdvajanje tipova&nbsp; stani&scaron;ta,&nbsp; o&nbsp; tipovima&nbsp; stani&scaron;ta,&nbsp; osetljivim, ugroženim,&nbsp; retkim&nbsp; i&nbsp; za&nbsp; za&scaron;titu&nbsp; prioritetnim tipovima&nbsp; stani&scaron;ta&nbsp; i&nbsp; o&nbsp; merama&nbsp; za&scaron;tite&nbsp; za&nbsp; njihovo očuvanje, Aneksu I, Direktive Evropske unije oza&scaron;titi&nbsp; prirodnih&nbsp; stani&scaron;ta&nbsp; i&nbsp; divlje&nbsp; flore&nbsp; i&nbsp; faune (Natura&nbsp; 2000),&nbsp; Rezoluciji&nbsp; br.&nbsp; 4&nbsp; Konvencije&nbsp; o očuvanju&nbsp; evropske&nbsp; divlje&nbsp; flore&nbsp; i&nbsp; faune&nbsp; i prirodnih&nbsp; stani&scaron;ta (EMERALD)&nbsp; i&nbsp; Evropskoj crvenoj&nbsp; listi&nbsp; stani&scaron;ta.&nbsp; Vrednosti&nbsp; izdvojenih atributa&nbsp; &scaron;ljunkara&nbsp; mogli&nbsp; bi&nbsp; se&nbsp; iskoristiti&nbsp; u procesu&nbsp; ranog&nbsp; planiranja&nbsp; i&nbsp; projektovanja eksploatacionih&nbsp; polja&nbsp; u&nbsp; plavnom&nbsp; području&nbsp; reke Drine&nbsp; i&nbsp; na&nbsp; drugim,&nbsp; sličnim&nbsp; lokalitetima. Generalna preporuka je da se dva tipa &scaron;ljunkara kreiraju&nbsp; u&nbsp; okviru&nbsp; jednog&nbsp; eksploatacionog&nbsp; polja. Prvi&nbsp; tip,&nbsp; odnosno&nbsp; &scaron;ljunkare&nbsp; koje&nbsp; bi&nbsp; podržavale pionirsku&nbsp; vegetaciju&nbsp; pr&scaron;ljenčica&nbsp; trebale&nbsp; bi&nbsp; da budu locirane na razdaljini do 100 m od glavnog rečnog&nbsp; toka,&nbsp; povr&scaron;ine&nbsp; do&nbsp; 1000&nbsp; m 2 i&nbsp; da&nbsp; imaju vrednost indeksa relativne dubine &gt; 5 %. Drugi tip&nbsp; &scaron;ljunkara&nbsp; koje&nbsp; bi&nbsp; podržavale&nbsp; vegetaciju karakterističnu&nbsp; za&nbsp; nizijska&nbsp; fluvijalna&nbsp; jezera trebale bi da budu locirane na razdaljani od oko 300 m od glavnog rečnog toka, dubine 3&nbsp; &ndash;&nbsp; 4&nbsp; m (najmanje 2 m), povr&scaron;ine između 10000 i 20000 m <sup>2 </sup>(najmanje&nbsp; 4000&nbsp; m<sup> 2</sup> ),&nbsp; različitih&nbsp; vrednosti indeksa relativne dubine, ali&nbsp; ne preko 5 %. Sva eksploataciona&nbsp; polja&nbsp; bi&nbsp; trebalo&nbsp; isplanirati&nbsp; i isprojektovati&nbsp; kako&nbsp; bi&nbsp; se&nbsp; minimizirao&nbsp; uticaj&nbsp; na priobalnu&nbsp; i&nbsp; obalnu&nbsp; zonu.&nbsp; Pridržavanjem&nbsp; datih smernica&nbsp; povećao&nbsp; bi&nbsp; se&nbsp; diverzitet&nbsp; i&nbsp; kvalitet stani&scaron;ta,&nbsp; kao&nbsp; i&nbsp; konzervacioni&nbsp; potencijal &scaron;ljunkara. Kreiranjem &scaron;ljunkara na naĉin kao &scaron;to je predloženo u ovoj disertaciji omogućila bi se spontana&nbsp; rekultivacija&nbsp; eksploatacionih polja,odnosno&nbsp; remedijacija&nbsp; u&nbsp; cilju&nbsp; pobolj&scaron;anja kvaliteta vode i renaturalizacija stani&scaron;ta, čime bi se&nbsp; znatno&nbsp; smanjili,&nbsp; ili&nbsp; u&nbsp; potpunosti&nbsp; eliminisali, tro&scaron;kovi tehničke rekultivacije terena.</p> / <p>Gravel pit lakes in the river floodplains represent a kind of ecological paradox. Gravel exploitation was recognised&nbsp; as&nbsp; important&nbsp; factor&nbsp; significantlyaffecting&nbsp; aquatic&nbsp; habitats&nbsp; and&nbsp; biodiversity.&nbsp; On the&nbsp; other&nbsp; hand,&nbsp; gravel&nbsp; pit&nbsp; lakes&nbsp; are&nbsp; valuable biodiversity&nbsp; refugiums,&nbsp; potentially&nbsp; supporting rarae&nbsp; species&nbsp; and&nbsp; habitats.&nbsp; The&nbsp; aim&nbsp; of&nbsp; this dissertation&nbsp; was&nbsp; to&nbsp; determine&nbsp; the&nbsp; most significant&nbsp; and&nbsp; relevant&nbsp; hydromorphological parameters&nbsp; in&nbsp; structuring&nbsp; macrophyte assemblages&nbsp; in gravel pit&nbsp; lakes along the Drina River floodplain and to determine the correlation between&nbsp; selected&nbsp; parameters&nbsp; and&nbsp; macrophyte quantitative&nbsp; indices.&nbsp; The&nbsp; research&nbsp; was&nbsp; carried out at the 18 gravel pit lakes (60 survey sectors) in&nbsp; Crna&nbsp; Bara,&nbsp; Badovinci&nbsp; and&nbsp; Lipnicki&nbsp; Sor&nbsp; and four natural fluvial lakes (13 survey sectors), in the&nbsp; Drina&nbsp; River&nbsp; floodplain&nbsp; during&nbsp; the&nbsp; summer months&nbsp; of&nbsp; 2015,&nbsp; 2016,&nbsp; 2017&nbsp; and&nbsp; 2018.Macrophyte&nbsp; vegetation&nbsp; was&nbsp; recorded&nbsp; in&nbsp; all&nbsp; 18 gravel pit lakes, in total supporting 31 taxa.&nbsp; The most&nbsp; abundant&nbsp; species,&nbsp; with&nbsp; highest&nbsp; tot al&nbsp; cover value&nbsp; were <em>Potamogeton</em>&nbsp; <em>nodosus,Ceratophyllum&nbsp;</em> demersum&nbsp; subsp.&nbsp; demersum,<em> Myriophyllum&nbsp; spicatum,&nbsp;</em> <em>Najas&nbsp; marina&nbsp;</em> and<em> Chara&nbsp; globularis</em>.&nbsp; Fluvial&nbsp; lakes&nbsp; supported&nbsp; 13 macrophyte&nbsp; taxa&nbsp; with&nbsp;<em> Vallisneria&nbsp; spiralis, Elodea&nbsp; canadensis,&nbsp; Callitriche&nbsp; palustris,Potamogeton&nbsp;</em> <em>natans&nbsp;</em> and&nbsp;<em> Nuphar&nbsp; lutea</em>&nbsp; as constant and dominant&nbsp; species.&nbsp; The values of all macrophyte&nbsp; quantitative&nbsp; indices&nbsp; found&nbsp; to&nbsp; be significantly&nbsp; higher&nbsp; in&nbsp; the&nbsp; gravel&nbsp; pit&nbsp; lakes compared&nbsp; to&nbsp; the&nbsp; fluvial&nbsp; ones.&nbsp; The&nbsp; cluster analysis&nbsp; revealed&nbsp; 14&nbsp; aquatic&nbsp; vegetation&nbsp; groups (VG).&nbsp; At&nbsp; 16&nbsp; out&nbsp; of&nbsp; 18&nbsp; gravel&nbsp; pit&nbsp; lakes&nbsp; 13 vegetation&nbsp; groups&nbsp; were&nbsp; revealed:&nbsp; VG1<em>Ceratophyllum&nbsp; demersum</em>,&nbsp; VG2&nbsp; <em>Ceratophyllum demersum- Valisneria&nbsp; spiralis</em>,&nbsp; VG3&nbsp;<em> Chara contraria</em>,&nbsp; VG4&nbsp; <em>Chara&nbsp; globularis</em>,&nbsp; VG5&nbsp;<em> Elodea&nbsp; canadensis,</em>&nbsp; VG6&nbsp;<em> Elodea&nbsp; nuttallii,</em>&nbsp; VG7&nbsp; <em>Najas marina,&nbsp;</em> VG8&nbsp;<em> Najas&nbsp; minor,</em>&nbsp; VG9&nbsp; <em>Nitellopsis obtusa</em>,&nbsp; VG10&nbsp; <em>Nuphar&nbsp; lutea,</em>&nbsp; VG11 <em>Potamogeton&nbsp; nodosus</em>,&nbsp; VG12&nbsp; <em>Potamogeton natans,</em> VG13&nbsp;<em> Potamogeton pectinatus</em>), Natural fluvial&nbsp; lakes&nbsp; supported&nbsp; 4&nbsp; vegetation&nbsp; groups: VG5&nbsp; <em>Elodea&nbsp; canadensis</em>,&nbsp; VG10&nbsp; <em>Nuphar&nbsp; lutea</em>, VG12&nbsp; <em>Potamogeton&nbsp; natans&nbsp;</em> and&nbsp; VG14&nbsp;<em> Typha latifolia</em>.&nbsp; All&nbsp; gravel&nbsp; pit&nbsp; lakes&nbsp; can&nbsp; be characterized&nbsp; as&nbsp; water&nbsp; bodies&nbsp; with&nbsp; good&nbsp; to maximal&nbsp; ecological&nbsp; potential,&nbsp; while&nbsp; all&nbsp; the fluvial ones can be characterized as water bidies with&nbsp; poor&nbsp; to&nbsp; moderate&nbsp; ecological&nbsp; status.&nbsp; The values&nbsp; of&nbsp; total&nbsp; suspended&nbsp; supstances,&nbsp; chemical and&nbsp; biological&nbsp; oxygen&nbsp; demand,&nbsp; total&nbsp; organic carbon&nbsp; and&nbsp; nitrates&nbsp; were&nbsp; significantly&nbsp; higher&nbsp; in the natural&nbsp; fluvial&nbsp; lakes compared to the gravel pit&nbsp; ones.&nbsp; Measured&nbsp; level&nbsp; of&nbsp; physico-chemical parameters&nbsp; indicating&nbsp; mesotrophic&nbsp; character&nbsp; of gravel&nbsp; pit&nbsp; lakes&nbsp; in&nbsp; Badovinci&nbsp; and&nbsp; mesoeutrophic&nbsp; in&nbsp; Lipnicki&nbsp; Sor,&nbsp; while&nbsp; all&nbsp; the&nbsp; gravel pits&nbsp; in&nbsp; Crna&nbsp; Bara&nbsp; could&nbsp; be&nbsp; characterized&nbsp; as eutrophic.&nbsp; Similar&nbsp; range&nbsp; values&nbsp; were&nbsp; calculated for&nbsp; LHQA&nbsp; for&nbsp; gravel&nbsp; pit&nbsp; and&nbsp; fluvial&nbsp; lakes&nbsp; (36 &ndash; 49). However, natural lakes&nbsp; showed significantly higher&nbsp; values&nbsp; for&nbsp; LHMS&nbsp; score.&nbsp; The&nbsp; above mentioned,&nbsp; indicates&nbsp; higher&nbsp; anthropogenic pressures&nbsp; on&nbsp; natural&nbsp; fluvial&nbsp; lakes&nbsp; compared&nbsp; to gravel&nbsp; pit&nbsp; ones.&nbsp; Physico-chemical&nbsp; and hydromorphological&nbsp; parameters&nbsp; together explained&nbsp; about&nbsp; 57&nbsp; %&nbsp; of&nbsp; the&nbsp; total&nbsp; variance&nbsp; of macrophyte&nbsp; assemblages&nbsp; with&nbsp; 16.57&nbsp; %&nbsp; of&nbsp; the shared effect. After accounting for the effects of physico-chemical&nbsp; parameters&nbsp; (17.02&nbsp; %), hydromorphological&nbsp; variables&nbsp; explained&nbsp; around 23 % of the total variance.&nbsp; The most significant water&nbsp; quality variables&nbsp; were: oxygen saturation, total&nbsp; organic&nbsp; carbon,&nbsp; surfactants, ,electroconductivity,&nbsp; pH&nbsp; and total alkalinity. The The most significant hydromorphology&nbsp; variables for&nbsp; structuring&nbsp; macrophyte&nbsp; assemblages&nbsp; were: riparian&nbsp; vegetation&nbsp; structural&nbsp; complexity, diversity&nbsp; of&nbsp; natural&nbsp; landcover&nbsp; types&nbsp; in&nbsp; riparianzone, shore structural habitat&nbsp; diversity, diversity of&nbsp; natural littoral zone, maximal&nbsp; lake depth, lake surface&nbsp; area,&nbsp; relative&nbsp; depth&nbsp; ratio,&nbsp; lake&nbsp; distance from&nbsp; r iver&nbsp; main&nbsp; channel&nbsp; and&nbsp; lake&nbsp;&nbsp; age.Hydrologycal parameters were explained 8.38 % of&nbsp; variance&nbsp; in&nbsp; structuring&nbsp; macrophyte assemblages.&nbsp; The&nbsp; most&nbsp; significant&nbsp; hydrology variables&nbsp; were&nbsp; the&nbsp; number&nbsp; of&nbsp; floods&nbsp; in vegetation&nbsp; season&nbsp; in&nbsp; first&nbsp; year&nbsp; when&nbsp; vegetation was sampled, and the number of spring floods in all four research years. These results&nbsp;&nbsp; confirm the direct destructive influence of summer floods&nbsp; on aquatic vegetation, as&nbsp;&nbsp; well as the indirect impact of&nbsp; spring&nbsp; floods,&nbsp; due&nbsp; to&nbsp; the&nbsp; impact&nbsp; on&nbsp; trophic status&nbsp; of&nbsp; water.&nbsp; Gravel&nbsp; pit&nbsp; lakes&nbsp; in&nbsp; te&nbsp; Drina River floodplain&nbsp; represent an optimal habitat&nbsp;&nbsp; for rare&nbsp; and&nbsp; threatened&nbsp; macrophyte&nbsp; flora.&nbsp; Of&nbsp; the total&nbsp; macrophyte&nbsp; species&nbsp; recorded,&nbsp; 30&nbsp; %&nbsp; were categorized&nbsp; as&nbsp; protected&nbsp; or threatened.&nbsp; At&nbsp; least one&nbsp; strictly&nbsp; protected,&nbsp; protected&nbsp; or&nbsp; threatened species&nbsp; was&nbsp; recorded&nbsp; in&nbsp; each&nbsp; gravel&nbsp; pit&nbsp; lake. Significantly&nbsp; higher&nbsp; values&nbsp; of&nbsp; conservation indices&nbsp; (C&nbsp; and&nbsp; Csp&nbsp; score)&nbsp; found&nbsp; to&nbsp; be significantly&nbsp; higher&nbsp; in&nbsp; the&nbsp; gravel&nbsp; pit&nbsp; lakes compared&nbsp; to&nbsp; the&nbsp; fluvial&nbsp; ones.&nbsp; High&nbsp; habitat diversity&nbsp; and&nbsp; conservation&nbsp; value&nbsp; of&nbsp; the&nbsp; sites have&nbsp; been&nbsp; recorded&nbsp; according&nbsp; to&nbsp; the&nbsp; National Rulebook,&nbsp; Annex&nbsp; I&nbsp; of&nbsp; Habitats&nbsp; Directive (NATURA 2000), Resolution&nbsp; no. 4 of the Bern Convention (EMERALD) and the European Red List&nbsp; of&nbsp; Habitats.&nbsp; Values&nbsp; of&nbsp; selected&nbsp; lake attributes can be used for early-design phases of future&nbsp; gravel&nbsp; extraction&nbsp; in&nbsp; the&nbsp; Drina&nbsp; River floodplain&nbsp; area,&nbsp; and&nbsp; in&nbsp; other&nbsp; similar&nbsp; sites. Therefore,&nbsp; general&nbsp; recommendations&nbsp; are&nbsp; that two gravel pit types should be excavated within the&nbsp; single&nbsp; extraction&nbsp; area&nbsp; in&nbsp; order&nbsp; to&nbsp; support pioneering charophyte vegetation and vegetation of typical eutrophic lowland floodplain lakes as well.&nbsp; The&nbsp; first&nbsp; hydromorphological&nbsp; lake&nbsp; type, suitable&nbsp; for&nbsp; stonewort&nbsp; species,&nbsp; should&nbsp; be excavated up to 100 m from river main channel, saving&nbsp; a&nbsp; surface&nbsp; area&nbsp; up&nbsp; to&nbsp; 1000&nbsp; m 2 and&nbsp; a relative depth ratio &gt; 5 %. The second gravel pit type&nbsp; should&nbsp; be&nbsp; located&nbsp; about&nbsp; 300&nbsp; m&nbsp; from&nbsp; river main channel, with preferable maximal depth inrange&nbsp; 3&ndash;4&nbsp; m&nbsp; (at&nbsp; least&nbsp; 2&nbsp; m&nbsp; depth),&nbsp; and&nbsp; a&nbsp; lake surface area between 10000 m 2 and 20000 m 2 (at least&nbsp; 4000&nbsp; m 2 ).&nbsp; Relative&nbsp; depth&nbsp; ratio&nbsp; may&nbsp; vary, but should be less than 5 %. Generally, all sites should&nbsp; be&nbsp; designed&nbsp; with&nbsp; the&nbsp; minimal&nbsp; impact to the&nbsp; riparian&nbsp; and&nbsp; shore&nbsp; zones.&nbsp; These&nbsp; proposed measures&nbsp; would&nbsp; considerably&nbsp; increase&nbsp; lake habitat diversity and their conservation potential. Creating&nbsp; gravel&nbsp; pit&nbsp; lakes&nbsp; as&nbsp; proposed&nbsp; in&nbsp; this dissertation&nbsp;&nbsp;&nbsp; would&nbsp; allow&nbsp; spontaneous recultivation&nbsp; of&nbsp; exploitation&nbsp; fields,&nbsp; remediation in&nbsp; order&nbsp; to&nbsp; improve&nbsp; water&nbsp; quality&nbsp; and renaturalization&nbsp; of&nbsp; habitats,&nbsp; which&nbsp; will significantly reduce, or completely eliminate, the costs of terrain technical recultivation.</p>
159

Development of guidelines for dealing with morphological and environmental impacts of sand mining along the Nzhelele River, Limpopo Province of South Africa

Mathada, Humphrey 22 January 2015 (has links)
MENVSC / Department of Geography and Geo-Information Sciences
160

Novostavba hotelu v Brně / Hotel in Brno

Babycheva, Daryna January 2022 (has links)
Subject of this diploma this is prepare a documentation for the construction of a hotel. Designed object is located in the Brno city. The hotel meets the conditions of a three-star (***) economic standard. It is designed with 18 accommodation units, of which 2 rooms for disabled. The hotel accommodates only 38 people. There is a restaurant with a terrace in the hotel too. Underground garages primarily designed for parking cars of hotel visitors. The object is designed in a rectangular shape. The construction system of the hotel is combined. Perimeter masonry in the upper floors is made of ceramic blocks, inside are a reinforced concrete skeleton. The foundation structure is designed as a system of waterproof concrete. The floor structure is designed as reinforced concrete slabs. The roofing will be solved by a flat roof with a gravel layer. The whole building is insulated to meet all the requirements of energy consumption of buildings. The main entrance is oriented to the west. In front of the building there is a parking space for hotel guests.

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