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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.
51

A apropria??o e percep??o de um rio urbano: o caso do ribeir?o Jacar? de Itatiba (SP)

Franco, Gustavo Cosenza de Almeida 16 February 2009 (has links)
Made available in DSpace on 2016-04-04T18:21:50Z (GMT). No. of bitstreams: 1 Gustavo Cosenza de Almeida Franco.pdf: 18932279 bytes, checksum: 4fefff2bba5f0f86bb6d112ccaaa7bf5 (MD5) Previous issue date: 2009-02-16 / This dissertation has as the main objective identify the people s perception and appropriation in relation with the urban rivers. The object of this study is the Jacar? brook, which is born and flows into the city named Itatiba (SP). With the help of a schedule and pre established standards, interviews were done with different segments of society organized civil society (ONG JAPPA), the municipal public power (mayor), regional water administration institutions (Committee and Consortium of basins), and common citizens which are familiar with the river. Our interviews interpretations allowed us identify the people s collective feelings about the Jacar? brook in the material area (landscape and environment) such as in the symbolic area (sentimental and affective). The definition of an urban river and its characteristic aspects also appear in this work. It aims to evince the relation between the river (water and river bank) and the population in front of the changes since the first quarter of the twenty century. The space that before was designated to leisure and social conviviality became a space hardly used and an urban level almost zero. What was possible to realize with the theorist base and with the interviews is that the complexities of the morphological dynamic of the cities environment reflect in the changes of the society values that used to be in these spaces. The clean river and the accesses to its bank propitiated activities that today are not possible, not only because of the conviviality space and social meeting, but also because the bad quality of these spaces (water and river banks). This study intended to understand the complexity of the relations in the water and urban environment areas, which embraces aspects of accesses, appropriation and a great faculty in the subjective area. Realize these relations, identify in people the feeling of belonging to a natural good and the values change that occurred contribute to a better understanding about the present scenery that embrace Jacar? brook and the futures perspectives of this relation. / Essa pesquisa teve como objetivo principal identificar a percep??o e a apropria??o das pessoas em rela??o aos rios urbanos. O objeto desse estudo foi o ribeir?o Jacar?, que nasce e des?gua na cidade de Itatiba (SP). Com o aux?lio de um roteiro e de crit?rios pr? estabelecidos, foram realizadas entrevistas com os diferentes segmentos da sociedade sociedade civil organizada (ONG JAPPA), poder p?blico municipal (prefeito), ?rg?os gestores da ?gua em ?mbito regional (Comit? e Cons?rcio de bacias), e, cidad?os comuns que se familiarizam com o rio. A nossa interpreta??o das entrevistas permitiu identificar os sentimentos coletivos das pessoas em rela??o ao ribeir?o Jacar?, tanto no campo f?sico (paisag?stico e ambiental) como no campo simb?lico (sentimental e afetivo). A defini??o de um rio urbano e seus aspectos caracter?sticos tamb?m aparece nesse trabalho. Procurou-se evidenciar a rela??o entre rio (?gua e margem) e a popula??o diante das mudan?as ocorridas a partir do primeiro quarto do s?culo XX. Observouse que um espa?o que antes se designava para o lazer e conv?vio social se transformou em um espa?o pouco utilizado e com um grau de urbanidade quase nulo. O que se p?de perceber com o embasamento te?rico e com as entrevistas ? que as complexidades da din?mica morfol?gica do ambiente das cidades refletem nas mudan?as de valores da sociedade que usufru?a e convivia nesses espa?os. O rio limpo e com disponibilidade de acesso ?s suas margens propiciava atividades que hoje se tornam invi?veis, n?o s? pelo pouco espa?o para o conv?vio e encontro social, mas tamb?m pela m? qualidade desses espa?os (tanto das ?guas quanto das margens). Esse estudo procurou compreender a complexidade das rela??es existentes no ?mbito da ?gua no meio urbano, o que envolve aspectos de acessibilidade, apropria??o e uma grande faculdade no campo subjetivo. Perceber essas rela??es, identificar nas pessoas o sentimento de pertencimento de um bem natural e a mudan?a de valores que ocorreram contribuem para uma melhor compreens?o sobre o cen?rio atual da intera??o do ribeir?o Jacar? na cidade e as perspectivas futuras dessa rela??o.
52

La gran obra hidràulica a les conques de la Muga i del Fluvià: dels projectes a les realitzacions (1850-1980)

Pavón, David 28 September 2007 (has links)
La tesi aborda, des d'una perspectiva territorial i històrica, el paper que han jugat les grans infraestructures hidràuliques en dues conques fluvials mediterrànies catalanes: la Muga i el Fluvià (província de Girona). Així, s'efectua una reconstrucció retrospectiva del conjunt de projectes de gran obra hidràulica (preses, embassaments, canals complementaris) que, als últims 150 anys, han estat ideats i, en el seu cas executats, a ambdues conques. En aquest procés s'atorga una atenció especial a les justificacions, finalitats, discursos i agents socials que han inspirat la seva concepció i les causes que han conduït al seu èxit o al seu fracàs. Tot plegat es contextualitza dins dels plans, les polítiques i la legislació hidràulica estatals. L'elecció de dos rius veïns proporciona clars elements per a establir una anàlisi evolutiva comparada entre ells. Aquí s'afegirà la influencia del proper riu Ter des del moment en que es decideix l'abastament parcial amb els seus cabals a Barcelona. / The aim of the thesis is to know the paper that the great hydraulic works have been in two mediterranean river basins called Muga and Fluvià located in Catalonia (province of Girona, Spain). The perspective of the study will be historical and territorial. The thesis realizes a retrospective reconstruction of the projects of great hydraulic works (dams/reservoirs + complementary channels) that have been conceived or built in both river basins during the last 150 years. In this process the study gives a special attention to their justifications, their aims, their peculiarities, their promoters, and the reasons of their issue or of their failure. All this is framed in the planification, policies, and hydraulic legislation pertaining to the state.The election of two neighbouring rivers provides the elements to establish an evolutional comparative analysis between both. Here we add the effects of the influence of the nearing Ter river, when is decided the partial supply with their waters to the city of Barcelona.
53

Use and Abuse of Southwestern Rivers: The Desert Farmer

Ayres, J. E. 23 April 1971 (has links)
From the Proceedings of the 1971 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 22-23, 1971, Tempe, Arizona / The pre-Columbian Hohokam Indians occupied the major river drainages of central Arizona, and have been the subject of much intense archaeological research. Evidence indicates that the Hohokam began using river water for crop irrigation about 300 B.C., and modified and improved their irrigation systems over time, until the maximum extent of these systems was achieved about 900 a. D. Two types of water control seem to have been utilized: (1) the direct exploitation of rivers through the use of irrigation canals, (2) indirect use through controlled runoff within microdrainages at higher elevations before it reached the rivers. At first, probably only those parcels of land with optimal soils and drainage were used, but apparently population increases fostered by agriculture itself, combined with increasing social and political complexity, necessitated more and more exploitation of marginal lands. Eventually soil problems increased, imposing severe limitations on agriculture. These involved salt and alkali accumulation due to inadequate drainage, soil density and water logging. Additionally, the extension of cropping required the clearing of natural vegetation, which resulted in increased erosion and decreased available native food resources for periods when crops failed. The culture vanished completely about 1450 a. D., probably mainly because of their manner of river exploitation for irrigation. More recent archaeological studies are concentrating not only on river use but also on river abuse.
54

Management Alternatives for Santa Cruz Basin Groundwater

Foster, K. E. 15 April 1978 (has links)
From the Proceedings of the 1978 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 14-15, 1978, Flagstaff, Arizona / Combined urban, agricultural, industrial and mining groundwater withdrawal from the Santa Cruz River Basin exceeds natural aquifer replenishment by 74,000 acre -feet annually. Four ameliorative water management alternatives are presented singly and in combination with one another. These alternatives are importing Colorado River water, exchanging treated effluent with mining and agricultural interests for groundwater, interbasin water transfer, and retiring farmlands for groundwater rights. These management philosophies are applicable to most economically emergent urban areas in arid and semiarid regions.
55

Paisagem útil:o Rio Tietê e a urbanização paulistana (1966 - 1986) / Useful landscape: Tietê River and São Paulo urbanization (1966-1986)

Alexandre Leitão Santos 07 May 2014 (has links)
A partir do processo de industrialização e crescimento urbano da cidade de São Paulo, o território do Rio Tietê passa a servir de suporte para uma série de aparatos técnicos e redes de infraestrutura essenciais ao funcionamento pleno da metrópole. Configura, assim, uma paisagem utilitária sobre a várzea. As diversas tentativas de controle do fluxo de suas águas não impediram, no entanto, que a relação entre cidade e ambiente se estabelecesse de modo conflituoso. Esta pesquisa reconhece que em meados dos anos 1960 ocorre uma inflexão na prática do planejamento urbano no Brasil e, consequentemente, no caráter dos projetos para o Rio Tietê. A consolidação dos sistemas de circulação sobre a várzea, o Estado como agente autoritário e centralizador e o advento dos planos de desenvolvimento regional, em conjunto com a problemática ecológica que se populariza nos anos 1970, marcam este período estudado. Propõe-se a compreender, neste âmbito, o papel dos urbanistas na definição das infraestruturas metropolitanas, especialmente nos casos estudados, e os limites e propósitos desta atribuição, deste modo contribuindo com a revisão da historiografia da arquitetura moderna brasileira, avançando na caracterização da produção urbanística pós-Brasília. / From the industrialization and urban growth process in São Paulo, the Tiete river territory become to provide support for a range of technical devices and infrastructure networks, that are essential to the full functioning of the metropolis, thus setting an utilitarian landscape over the floodplain. The various attempts to control the flow of its waters did not prevent, however, that the relationship between the city and the environment to be conflicting. This research recognizes in the mid-1960s an inflection in the practice of urban planning in Brazil and consequently in the character of the projects for the Tiete river. The consolidation of circulation systems on the floodplain, the state as an authoritarian and centralizing agent and the advent of regional development plans, together with the ecological problem that became popular in the 1970s, marks this studied period. It is proposed to understand, in this context, the role of planners in the definition of metropolitan infrastructure, especially in the studied cases, and the limits and purposes of this assignment, thereby contributing to the revision of the historiography of modern Brazilian architecture, contributing for characterization of the brazilian urbanistic production post Brasília.
56

Developing integrated management of ephemeral river basins in Botswana : the case of Boteti river sub-basin

Motsholapheko, Moseki Ronald 04 1900 (has links)
Botswana is a water scarce country. Rainfall is highly variable, leading to limited surface and groundwater resources. Due to persistently dry conditions most rivers found in Botswana are ephemeral. The Boteti River sub-Basin is one of the numerous ephemeral river sub-Basins, in Botswana. Key environmental challenges, resulting from human activities, in the sub-Basin are: increased pressure on local resources due to overstocking, overgrazing and over-harvesting; reductions in wildlife numbers; denudation of vegetation and the resultant exposure of the soil to wind erosion. As a major step, to pilot implementation of river basin management in the ephemeral river basins in southern Africa, the Boteti River sub-Basin is one of the key areas identified for study under the Ephemeral River Basins in the Southern African Development Community SADC (ERBSADC) Project. This study was initiated, as part of the ERB-SADC project and its aim is to investigate the socio-economic status of the Boteti River sub-Basin and determine the potential for developing integrated management of water and land resources in the sub- Basin. Its key objectives are to identify and assess types and patterns of water use; to identify and assess key livelihood activities; and to critically assess community participation in water resources management in the sub-Basin. A questionnaire was administered to 293 households, a focus group discussion was held with twelve community representatives of six villages in the sub-Basin, six traditional leaders and five local government officers were interviewed as key informants, and informal discussions were held with three local farmers. Results from the study indicate low livelihood levels based on livestock and arable agriculture, high dependence on natural resources and low participation of communities in water management. The study concludes that a livelihood approach to integrated water resources management can help deal with environmental challenges and enhance community participation. / Environmental Sciences / Thesis (M.A. (Environmental Science))
57

Developing integrated management of ephemeral river basins in Botswana : the case of Boteti river sub-basin

Motsholapheko, Moseki Ronald 04 1900 (has links)
Botswana is a water scarce country. Rainfall is highly variable, leading to limited surface and groundwater resources. Due to persistently dry conditions most rivers found in Botswana are ephemeral. The Boteti River sub-Basin is one of the numerous ephemeral river sub-Basins, in Botswana. Key environmental challenges, resulting from human activities, in the sub-Basin are: increased pressure on local resources due to overstocking, overgrazing and over-harvesting; reductions in wildlife numbers; denudation of vegetation and the resultant exposure of the soil to wind erosion. As a major step, to pilot implementation of river basin management in the ephemeral river basins in southern Africa, the Boteti River sub-Basin is one of the key areas identified for study under the Ephemeral River Basins in the Southern African Development Community SADC (ERBSADC) Project. This study was initiated, as part of the ERB-SADC project and its aim is to investigate the socio-economic status of the Boteti River sub-Basin and determine the potential for developing integrated management of water and land resources in the sub- Basin. Its key objectives are to identify and assess types and patterns of water use; to identify and assess key livelihood activities; and to critically assess community participation in water resources management in the sub-Basin. A questionnaire was administered to 293 households, a focus group discussion was held with twelve community representatives of six villages in the sub-Basin, six traditional leaders and five local government officers were interviewed as key informants, and informal discussions were held with three local farmers. Results from the study indicate low livelihood levels based on livestock and arable agriculture, high dependence on natural resources and low participation of communities in water management. The study concludes that a livelihood approach to integrated water resources management can help deal with environmental challenges and enhance community participation. / Environmental Sciences / Thesis (M.A. (Environmental Science))
58

Компаративна анализа ерозије земљишта у Хомољу и Звижду / Komparativna analiza erozije zemljišta u Homolju i Zviždu / Comparative analysis of the soil erosion in Homolje and Zvižd

Mladenović Ben 24 April 2013 (has links)
<p>Ерозија земљишта је један од најкомплекснијих проблема и уједно један од најподмуклијих човекових непријатеља. Ерозивни процеси постепено разарају и уништавају земљиште, односе хранљиве супстрате и ремете водни режим. Они доводе становништво многих, често пространих области у беду, сиромаштво и миграцију. Због тога, многе привредне гране морају бити увучене у борбу против ерозије земљишта и њених страховитих последица. Ерозија је веома сложена динамичка појава, која зависи од низа фактора чије је диференцирање врло тешко. Испитивање и утврђивање интензитета водне ерозије спада у групу проблема који се не могу свеобухватно решити. Веома је тешко, скоро немогуће, издвојити све факторе, а потом мултиплицирати све те факторе у свим постојећим комбинацијама. Овим радом сагледано је стање ерозије земљишта у сливу Млаве и Пека, односно Хомољу и Звижду, са више аспеката и утврђен низ појава као што су: концентрација растворених минералних материја, процентуално учешће макроелемената у укупној минерализацији, однос минерализације према протицају, укупан годишњи пронос растворених минералних материја, однос специфичне електричне проводљивости и укупне минерализације, износ хемијске евакуације, износ хемијски растворених минералних материја које потичу од стенског комлекса у сливу, утицај геолошког састава на укупну минерализацију воде, њену структуру и специфичну хемијску ерозију, концентрација суспендованог наноса по профилима, однос суспендованог наноса према протицају, укупан годишњи пронос суспендованог наноса као и специфична ерозија, утицај сезонских фактора на концентрацију силта и износ механичке ерозије, утицај геолошког састава на укупан пронос суспендованог наноса, мерење вученог наноса, однос хемијске и механичке ерозије. Хомоље и Звижд највећим делом припадају брдско &ndash; планинском подручју које се одликује водотоковима са релативно великим уздужним падовима, где су углови нагиба од 10 до 40. у Хомољу и Звижду све водотокове карактеришу врло велике разлике између екстремно великих и малих вода, па на неким водотоковима однос максималних и минималних протицаја достиже вредност и хиљаду. Овакав однос између малих и великих вода погодује развоју ерозивних процеса и разарању земљишта. Ерозија у сливу која почиње плувијалном ерозијом, а наставља се денудацијом, доводи до снижавања топографске површине и еродирања&nbsp; земљишта. Таложењем наноса на дну речног корита оно се издиже, што доводи до смањивања&nbsp;овлаженог профила. Велике поплавне воде због тога не могу да протекну тако&nbsp;оплићалим речним коритом, па због тога долази до њиховог изливања, што се&nbsp;манифестује поплавама. Без земљишта остају горњи делови слива, а поплавама,&nbsp;услед таложења вученог и суспендованог наноса на дну речног корита, бивају&nbsp;изложени доњи делови речних токова. Овакав негативан тренд уочен је и у Хомољу&nbsp;и у Звижду који су последњих година све чешће угрожени поплавним водама које&nbsp;причињавају велике штете како пољопривредном земљишту тако и насељима у сливовима Млаве и Пека. С обзиром на чињеницу да у Хомољу и Звижду постоји велики број бујичних токова који носе огромне количине наноса, реално је очекивање да ће се тај нанос акумулирати у средњем и доњем делу сливова Млаве и Пека. Избор хидротехничког метода за истраживање обима и интензитета ерозије у Хомољу и Звижду, као и коришћење методе професора С. Гавриловића у анализи бујичних токова је покушај прецизнијег утврђивања квантитета овог процеса који последњих година има узлазни тренд. Остварење постављених задатака утврђеном методологијом и постигнуће задатих циљева пружа одговор на питање колики је интензитет и обим процеса ерозије у Хомољу и Звижду на годишњем нивоу, по годишњим добима и месецима. Утврђен је степен деловања физичко &ndash; географских фактора који имају утицај на процес ерозије, указано је на обим и врсту примене антиерозивних мера, нарочито у сливовима бујичних токова. Сагледавањем интензитета и обима ерозије у Хомољу и Звижду, односно сливовима Млаве и Пека, успешније ће бити решени водопривредни проблеми који овде постоје.&nbsp;</p> / <p>Erozija zemljišta je jedan od najkompleksnijih problema i ujedno jedan od najpodmuklijih čovekovih neprijatelja. Erozivni procesi postepeno razaraju i uništavaju zemljište, odnose hranljive supstrate i remete vodni režim. Oni dovode stanovništvo mnogih, često prostranih oblasti u bedu, siromaštvo i migraciju. Zbog toga, mnoge privredne grane moraju biti uvučene u borbu protiv erozije zemljišta i njenih strahovitih posledica. Erozija je veoma složena dinamička pojava, koja zavisi od niza faktora čije je diferenciranje vrlo teško. Ispitivanje i utvrđivanje intenziteta vodne erozije spada u grupu problema koji se ne mogu sveobuhvatno rešiti. Veoma je teško, skoro nemoguće, izdvojiti sve faktore, a potom multiplicirati sve te faktore u svim postojećim kombinacijama. Ovim radom sagledano je stanje erozije zemljišta u slivu Mlave i Peka, odnosno Homolju i Zviždu, sa više aspekata i utvrđen niz pojava kao što su: koncentracija rastvorenih mineralnih materija, procentualno učešće makroelemenata u ukupnoj mineralizaciji, odnos mineralizacije prema proticaju, ukupan godišnji pronos rastvorenih mineralnih materija, odnos specifične električne provodljivosti i ukupne mineralizacije, iznos hemijske evakuacije, iznos hemijski rastvorenih mineralnih materija koje potiču od stenskog komleksa u slivu, uticaj geološkog sastava na ukupnu mineralizaciju vode, njenu strukturu i specifičnu hemijsku eroziju, koncentracija suspendovanog nanosa po profilima, odnos suspendovanog nanosa prema proticaju, ukupan godišnji pronos suspendovanog nanosa kao i specifična erozija, uticaj sezonskih faktora na koncentraciju silta i iznos mehaničke erozije, uticaj geološkog sastava na ukupan pronos suspendovanog nanosa, merenje vučenog nanosa, odnos hemijske i mehaničke erozije. Homolje i Zvižd najvećim delom pripadaju brdsko &ndash; planinskom području koje se odlikuje vodotokovima sa relativno velikim uzdužnim padovima, gde su uglovi nagiba od 10 do 40. u Homolju i Zviždu sve vodotokove karakterišu vrlo velike razlike između ekstremno velikih i malih voda, pa na nekim vodotokovima odnos maksimalnih i minimalnih proticaja dostiže vrednost i hiljadu. Ovakav odnos između malih i velikih voda pogoduje razvoju erozivnih procesa i razaranju zemljišta. Erozija u slivu koja počinje pluvijalnom erozijom, a nastavlja se denudacijom, dovodi do snižavanja topografske površine i erodiranja&nbsp; zemljišta. Taloženjem nanosa na dnu rečnog korita ono se izdiže, što dovodi do smanjivanja&nbsp;ovlaženog profila. Velike poplavne vode zbog toga ne mogu da proteknu tako&nbsp;oplićalim rečnim koritom, pa zbog toga dolazi do njihovog izlivanja, što se&nbsp;manifestuje poplavama. Bez zemljišta ostaju gornji delovi sliva, a poplavama,&nbsp;usled taloženja vučenog i suspendovanog nanosa na dnu rečnog korita, bivaju&nbsp;izloženi donji delovi rečnih tokova. Ovakav negativan trend uočen je i u Homolju&nbsp;i u Zviždu koji su poslednjih godina sve češće ugroženi poplavnim vodama koje&nbsp;pričinjavaju velike štete kako poljoprivrednom zemljištu tako i naseljima u slivovima Mlave i Peka. S obzirom na činjenicu da u Homolju i Zviždu postoji veliki broj bujičnih tokova koji nose ogromne količine nanosa, realno je očekivanje da će se taj nanos akumulirati u srednjem i donjem delu slivova Mlave i Peka. Izbor hidrotehničkog metoda za istraživanje obima i intenziteta erozije u Homolju i Zviždu, kao i korišćenje metode profesora S. Gavrilovića u analizi bujičnih tokova je pokušaj preciznijeg utvrđivanja kvantiteta ovog procesa koji poslednjih godina ima uzlazni trend. Ostvarenje postavljenih zadataka utvrđenom metodologijom i postignuće zadatih ciljeva pruža odgovor na pitanje koliki je intenzitet i obim procesa erozije u Homolju i Zviždu na godišnjem nivou, po godišnjim dobima i mesecima. Utvrđen je stepen delovanja fizičko &ndash; geografskih faktora koji imaju uticaj na proces erozije, ukazano je na obim i vrstu primene antierozivnih mera, naročito u slivovima bujičnih tokova. Sagledavanjem intenziteta i obima erozije u Homolju i Zviždu, odnosno slivovima Mlave i Peka, uspešnije će biti rešeni vodoprivredni problemi koji ovde postoje.&nbsp;</p> / <p>The abstract has been processed with OCR optical text recognition technology.</p><p>Soil erosion is one of the most complex problems and at the same time one of the most insidious of human enemies. Erosion processes gradually destroy the land, carry away nutritional substrates and disrupt the water regime. They drive many people, often from large areas, to misery and poverty, and cause migration. Therefore, many industries have to be included into the fight against soil erosion and its terrible consequences. Erosion is a very complex and dynamic phenomenon that relies on many factors which are hard to define. Differentiating and determining the intensity of water erosion are among the problems that cannot be comprehensively solved. It is very difficult, almost impossible, to extract all the factors and then multiply all these factors in every possible combination. This paper looks at the situation with soil erosion in the water basins of the rivers Mlava and Pek respectively, that is, in the areas of Homolje and Zvižd, from various aspects, and identifies a series of phenomena such as concentration of dissolved minerals, percentage of macroelements in the total mineralization, the relationship of mineralization to the flow, the total annual transport of dissolved minerals, the ratio of the specific electrical conductivity and total mineralization, the amount of chemical evacuation, the amount of chemically dissolved minerals that come from the rock complex in the basin, the impact of geological composition on the total mineralization of water, its structure and specific chemical erosion, suspended sediment concentration by profiles, the effect of suspended sediment on the flow, the total annual transport of suspended sediment as well as the specific erosion, the impact of seasonal factors on the concentration of silt and the amount of mechanical erosion, the impact of geological composition on the total transport of suspended sediment, bed load measurement, the ratio of chemical and mechanical erosion. Homolje and Zvižd are mostly hilly and mountainous areas characterized by water streams with relatively large vertical drops where the pitch angles may vary from 10&deg; to 40&deg;. In Homolje and Zvižd all the waterways are characterized by very large differences between extremely high and low water, reaching the value of a thousand in some points. This kind of a ratio between high and low waters favors the development of erosion processes and the destruction of land. Erosion in a basin starts with a pluvial erosion and continues with denudation, causing the lowering of the topographic surface and soil erosion. When the sediment deposits at the bottom of the river bed, the bed rises, leading to a reduction of the humidified profile. Therefore great floodwater cannot pass through such a shallow riverbed, which leads to its discharge and causes a flood. The upper parts of the basin lose land, and the lower parts of the basin become exposed to floods due to the deposition of bed load and suspended sediment at the bottom of the riverbed. This negative trend has been observed both in Homolje and Zviždi which in recent years have become increasingly threatened by flood waters which cause great damage to agricultural land and settlements in the basins of the rivers Mlava and Pek. Considering the fact that Homolje and Zvižd there is a large number of torrential streams that carry huge amounts of sediment, it is reasonable to expect the sediment to accumulate in the middle and lower parts of the basins of Mlava and Pek. The selection of the hydrotechnical method to explore the scope and intensity of erosion in Homolje and Zvižd, and the use of Professor S. Gavrilović&rsquo;s method in the analysis of torrential flows is an attempt to determine more precisely the quantity of this process with an increasing trend in recent years. Fulfillment of tasks and achievement of objectives through suggested methodology and achievement of objectives provides the answer to the question of intensity and extent of erosion in Homolje and Zvižd on an annual basis, according to seasons and months. The paper has determined the degree of impact of physical and geographic factors on the erosion process, and has pointed to the scope and type of application anti-erosion measures, especially in watersheds with torrential flows. If we manage to comprehend the intensity and extent of erosion in Homolje and Zvižd, that is, in the basins of Mlava and Pek, we will be able to solve the existing water management problems more successfully.</p>

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