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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 aggregatesΣπυρόπουλος, 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.
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Compressibility Of Various Coarse-grained Fill Materials In Dry And Wet Loading Conditions In Oedometer TestKayahan, 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.
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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?ceosSilva Junior, Francisco Alves da 30 May 2014 (has links)
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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
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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 TOBACCOSchuck, 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.
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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)
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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.
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Morphodynamique des bancs alternés d'une rivière de montagne aménagée / Alternate-Bar morphodynamics in an engineered mountains riverJaballah, 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.
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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 AfricaDiedericks, 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.
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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 RiverfloodplainDamnjanovic Bojan 03 December 2019 (has links)
<p>Sa jedne strane se eksploatacija šljunka navodi kao značajan ugrožavajući faktor sa velikim negativnim uticajem na vodena staništa i biodiverzitet, dok same šljunkare mogu predstavljati vredne refugijume akavtičnog biodiverziteta. Osnovni cilj disertacije je određivanje najznačajnijih i relevantnih hidromorfoloških parametara koji utiču na strukturiranje makrofitskih zajednica u šljunkarama duž plavnog područja reke Drine i određivanje korelacije između izdvojenih parametara i kvantitativnih indeksa makrofita.Istraživanje je vršeno u toku letnjih meseci 2015, 2016, 2017 i 2018. godine na 18 šljunkara (60 istraživačkih vegetacijskih sektora) u okviru tri eksploataciona polja u Crnoj Bari, Badovincima i Lipničkom Šoru i na četiri prirodna fluvijalna jezera (13 istraživačkih vegetacijskih sektora) u plavnom području reke Drine. Makrofitska vegetacija je konstatovana na svih 18 istraţivanih šljunkara, prikupljenih na tri eksploataciona polja (Badovinci, Crna Bara i<br />Lipniĉki Šor). Zabeležena je 31 biljna vrsta. Kao najučestalije, sa najvećom apsolutnom pokrovnošću izdvojile su se vrste: <em> Potamogeton nodosus</em> Poiret, <em>Ceratophyllum demersum L subsp. demersum, Myriophyllum spicatum L,Najas marina L i Chara globularis Thuill </em> Na četiri prirodna fluvijalna jezera zabeleženo je 13 vrsta. Vrste <em>Vallisneria spiralis L, Elodea canadensis Michx, Callitriche palustris L, Potamogeton natans L i Nuphar lutea (L) </em> Sm izdvojile su se kao konstantne i dominantne. Vrednosti svih kvantitativnih indeksa makrofita,<br />značajno su veće za šljunkare u poređenju sa prirodnim fluvijalnim jezerima na nivouLEAFPACS sektora. Na istraživanim šljunkarama, analizom klasterovanja je<br />izdvojeno 13 vegetacijskih grupa (VG): VG1<em> Ceratophyllum demersum</em>, VG2 <em>Ceratophyllum demersum - Valisneria spiralis</em>, VG3 <em>Chara contraria,</em> VG4 <em>Chara</em> <em>globularis,</em> VG5 <em>Elodea canadensis,</em> VG6 <em>Elodea nuttallii</em>, VG7 <em>Najas marina</em>, VG8 <em>Najas minor,</em> VG9 <em>Nitellopsis obtusa</em>, VG10 <em> Nuphar lutea</em>, VG11 <em>Potamogeton nodosus</em>, VG12 <em> Potamogeton natans </em> i VG13 <em>Potamogeton pectinatus</em>. Na prirodnim fluvijalnim jezerima konstatovane su četiri vegetacijske grupe: VG5 <em> Elodea canadensis</em>, VG10 <em>Nuphar lutea,</em> VG12<em> Potamogeton natans </em> i VG14 <em>Typha latifolia</em>. Na osnovu izmerenih fizičko-hemijskih parametara,kvalitet vode u većini šljunkara odgovara II klasi kvaliteta, na osnovu čega se mogu okarakterisati kao vodna tela sa dobrim i boljim ekološkim potencijalom. Sve šljunkare i fluvijalna jezera se klasifikuju kao visoko alkalna. Kvalitet vode u prirodnim fluvijalnim jezerima odgovara III – IV klasi kvaliteta voda, pri čemu se mogu okarakterisati kao vodna tela sa slabim do umerenim ekološkim statusom. Značajno veće<br />vrednosti ukupnih suspendovanih materija, hemijske i biološke potrošnje kiseonika, ukupnog organskog kiseonika i nitrata zabeležene su na prirodnim fluvijalnim jezerima u poređenju sa šljunkarama. Izmerene vrednosti fizičko-hemijskih parametara ukazuju na mezotrofni karakter lokaliteta u Badovincima i mezo-eutrofni karakter lokaliteta u Lipničkom Šoru, dok se šljunkare na teritoriji Crne Bare mogu okarakterisati kao eutrofna jezera.Vrednosti LHMS (modifikacionog) skora za šljunkare kretale su se u rasponu od 9 – 15, dok su vrednosti LHQA skora (stanišnog diverziteta) bile u rasponu izmeĊu 33 – 44. Sliĉne vrednosti za LHQA skor su izraĉunate i za prirodna fluvijalna jezera (36 – 49). MeĊutim, vrednosti<br />LHMS skora za prirodna fluvijalna jezera su znaĉajno veće u odnosu na vrednosti LHMS skora za šljunkare. Ovi podaci ukazuju na manje prisustvo antropogenog pritiska na šljunkarama u poređenju sa prirodnim fluvijalnim jezerima uistraţivanom podruĉju. Fizičko -hemijski i hidromorfološki parametri zajedno su objasnili 57.07 % od ukupne varijanse vegetacijskih podataka, sa 16.57 % deljenog efekta. Fizičkohemijski parametri kvaliteta vode objasnili su 17.02 % varijabilnosti u strukturi makrofitske vegetacije. Kao najsignifikantniji parametri<br />izdvojili su se: saturacija vode kiseonikom,ukupni organski ugljenik, površinski aktivne materije, temperatura, elektroprovodljivost, pH i ukpni alkalitet. Hidromorfološki parametri su objasnili 23.48 % varijabilnosti u strukturi makrofitske vegetacije. Kao najsignifikantnije varijable, izdvojile su se: struktura vegetacije u priobalnoj zoni, diverzitet prirodnih tipova staništa priobalne zone, prirodnost obale, diverzitet prirodnog supstrata litorala,masimalna dubina šljunkara, površina šljunkara,indeks relativne dubine, udaljenost šljunkara od glavnog reĉnog toka i starost šljunkara. Hidrološki parametri su objasnili 8.38 % varijabilnosti u strukturi makrofitske vegetacije. Kao najsignifikantnije varijable, izdvojile su se broj plavnih talasa u vegetacionoj sezoni tokom godine u kojoj je vršeno uzorkovanje vegetacije i broj plavnih talasa u prolećnom periodu za sve četiri godine. Ovi rezultati potvrđuju direktni destruktivni uticaj plavnih talasa na vodenu vegetaciju u vegetacionoj sezoni, kao i indirektni uticaj prolećnih poplava, usled uticaja na trofički status vode. Sumarno, šljunkare u plavnom području reke Drine predstavljaju optimalno stanište za razvoj retke i ugroţene makrofitske flore. Od ukupnog broja zabeleženih vrsta makrofita, 30 % se kategoriše kao zaštićeno ili ugroženo na nacionalnom nivou. Značajno veće vrednosti konzervacionih indeksa ustanovljene su za šljunkare u poređenju sa prirodnim fluvijalnim jezerima, što ukazuje na njihov visok ekološki potencijal. Ustanovljen je visok diverzitet prioritetnih tipova akvatiĉnih staništa prema Pravilniku o kriterijumima za izdvajanje tipova staništa, o tipovima staništa, osetljivim, ugroženim, retkim i za zaštitu prioritetnim tipovima staništa i o merama zaštite za njihovo očuvanje, Aneksu I, Direktive Evropske unije ozaštiti prirodnih staništa i divlje flore i faune (Natura 2000), Rezoluciji br. 4 Konvencije o očuvanju evropske divlje flore i faune i prirodnih staništa (EMERALD) i Evropskoj crvenoj listi staništa. Vrednosti izdvojenih atributa šljunkara mogli bi se iskoristiti u procesu ranog planiranja i projektovanja eksploatacionih polja u plavnom području reke Drine i na drugim, sličnim lokalitetima. Generalna preporuka je da se dva tipa šljunkara kreiraju u okviru jednog eksploatacionog polja. Prvi tip, odnosno šljunkare koje bi podržavale pionirsku vegetaciju pršljenčica trebale bi da budu locirane na razdaljini do 100 m od glavnog rečnog toka, površine do 1000 m 2 i da imaju vrednost indeksa relativne dubine > 5 %. Drugi tip šljunkara koje bi podržavale vegetaciju karakterističnu za nizijska fluvijalna jezera trebale bi da budu locirane na razdaljani od oko 300 m od glavnog rečnog toka, dubine 3 – 4 m (najmanje 2 m), površine između 10000 i 20000 m <sup>2 </sup>(najmanje 4000 m<sup> 2</sup> ), različitih vrednosti indeksa relativne dubine, ali ne preko 5 %. Sva eksploataciona polja bi trebalo isplanirati i isprojektovati kako bi se minimizirao uticaj na priobalnu i obalnu zonu. Pridržavanjem datih smernica povećao bi se diverzitet i kvalitet staništa, kao i konzervacioni potencijal šljunkara. Kreiranjem šljunkara na naĉin kao što je predloženo u ovoj disertaciji omogućila bi se spontana rekultivacija eksploatacionih polja,odnosno remedijacija u cilju poboljšanja kvaliteta vode i renaturalizacija staništa, čime bi se znatno smanjili, ili u potpunosti eliminisali, troškovi tehničke rekultivacije terena.</p> / <p>Gravel pit lakes in the river floodplains represent a kind of ecological paradox. Gravel exploitation was recognised as important factor significantlyaffecting aquatic habitats and biodiversity. On the other hand, gravel pit lakes are valuable biodiversity refugiums, potentially supporting rarae species and habitats. The aim of this dissertation was to determine the most significant and relevant hydromorphological parameters in structuring macrophyte assemblages in gravel pit lakes along the Drina River floodplain and to determine the correlation between selected parameters and macrophyte quantitative indices. The research was carried out at the 18 gravel pit lakes (60 survey sectors) in Crna Bara, Badovinci and Lipnicki Sor and four natural fluvial lakes (13 survey sectors), in the Drina River floodplain during the summer months of 2015, 2016, 2017 and 2018.Macrophyte vegetation was recorded in all 18 gravel pit lakes, in total supporting 31 taxa. The most abundant species, with highest tot al cover value were <em>Potamogeton</em> <em>nodosus,Ceratophyllum </em> demersum subsp. demersum,<em> Myriophyllum spicatum, </em> <em>Najas marina </em> and<em> Chara globularis</em>. Fluvial lakes supported 13 macrophyte taxa with <em> Vallisneria spiralis, Elodea canadensis, Callitriche palustris,Potamogeton </em> <em>natans </em> and <em> Nuphar lutea</em> as constant and dominant species. The values of all macrophyte quantitative indices found to be significantly higher in the gravel pit lakes compared to the fluvial ones. The cluster analysis revealed 14 aquatic vegetation groups (VG). At 16 out of 18 gravel pit lakes 13 vegetation groups were revealed: VG1<em>Ceratophyllum demersum</em>, VG2 <em>Ceratophyllum demersum- Valisneria spiralis</em>, VG3 <em> Chara contraria</em>, VG4 <em>Chara globularis</em>, VG5 <em> Elodea canadensis,</em> VG6 <em> Elodea nuttallii,</em> VG7 <em>Najas marina, </em> VG8 <em> Najas minor,</em> VG9 <em>Nitellopsis obtusa</em>, VG10 <em>Nuphar lutea,</em> VG11 <em>Potamogeton nodosus</em>, VG12 <em>Potamogeton natans,</em> VG13 <em> Potamogeton pectinatus</em>), Natural fluvial lakes supported 4 vegetation groups: VG5 <em>Elodea canadensis</em>, VG10 <em>Nuphar lutea</em>, VG12 <em>Potamogeton natans </em> and VG14 <em> Typha latifolia</em>. All gravel pit lakes can be characterized as water bodies with good to maximal ecological potential, while all the fluvial ones can be characterized as water bidies with poor to moderate ecological status. The values of total suspended supstances, chemical and biological oxygen demand, total organic carbon and nitrates were significantly higher in the natural fluvial lakes compared to the gravel pit ones. Measured level of physico-chemical parameters indicating mesotrophic character of gravel pit lakes in Badovinci and mesoeutrophic in Lipnicki Sor, while all the gravel pits in Crna Bara could be characterized as eutrophic. Similar range values were calculated for LHQA for gravel pit and fluvial lakes (36 – 49). However, natural lakes showed significantly higher values for LHMS score. The above mentioned, indicates higher anthropogenic pressures on natural fluvial lakes compared to gravel pit ones. Physico-chemical and hydromorphological parameters together explained about 57 % of the total variance of macrophyte assemblages with 16.57 % of the shared effect. After accounting for the effects of physico-chemical parameters (17.02 %), hydromorphological variables explained around 23 % of the total variance. The most significant water quality variables were: oxygen saturation, total organic carbon, surfactants, ,electroconductivity, pH and total alkalinity. The The most significant hydromorphology variables for structuring macrophyte assemblages were: riparian vegetation structural complexity, diversity of natural landcover types in riparianzone, shore structural habitat diversity, diversity of natural littoral zone, maximal lake depth, lake surface area, relative depth ratio, lake distance from r iver main channel and lake age.Hydrologycal parameters were explained 8.38 % of variance in structuring macrophyte assemblages. The most significant hydrology variables were the number of floods in vegetation season in first year when vegetation was sampled, and the number of spring floods in all four research years. These results confirm the direct destructive influence of summer floods on aquatic vegetation, as well as the indirect impact of spring floods, due to the impact on trophic status of water. Gravel pit lakes in te Drina River floodplain represent an optimal habitat for rare and threatened macrophyte flora. Of the total macrophyte species recorded, 30 % were categorized as protected or threatened. At least one strictly protected, protected or threatened species was recorded in each gravel pit lake. Significantly higher values of conservation indices (C and Csp score) found to be significantly higher in the gravel pit lakes compared to the fluvial ones. High habitat diversity and conservation value of the sites have been recorded according to the National Rulebook, Annex I of Habitats Directive (NATURA 2000), Resolution no. 4 of the Bern Convention (EMERALD) and the European Red List of Habitats. Values of selected lake attributes can be used for early-design phases of future gravel extraction in the Drina River floodplain area, and in other similar sites. Therefore, general recommendations are that two gravel pit types should be excavated within the single extraction area in order to support pioneering charophyte vegetation and vegetation of typical eutrophic lowland floodplain lakes as well. The first hydromorphological lake type, suitable for stonewort species, should be excavated up to 100 m from river main channel, saving a surface area up to 1000 m 2 and a relative depth ratio > 5 %. The second gravel pit type should be located about 300 m from river main channel, with preferable maximal depth inrange 3–4 m (at least 2 m depth), and a lake surface area between 10000 m 2 and 20000 m 2 (at least 4000 m 2 ). Relative depth ratio may vary, but should be less than 5 %. Generally, all sites should be designed with the minimal impact to the riparian and shore zones. These proposed measures would considerably increase lake habitat diversity and their conservation potential. Creating gravel pit lakes as proposed in this dissertation would allow spontaneous recultivation of exploitation fields, remediation in order to improve water quality and renaturalization of habitats, which will significantly reduce, or completely eliminate, the costs of terrain technical recultivation.</p>
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Development of guidelines for dealing with morphological and environmental impacts of sand mining along the Nzhelele River, Limpopo Province of South AfricaMathada, Humphrey 22 January 2015 (has links)
MENVSC / Department of Geography and Geo-Information Sciences
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Novostavba hotelu v Brně / Hotel in BrnoBabycheva, 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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