• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 1
  • 1
  • Tagged with
  • 2
  • 2
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 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.
1

Evolução do uso da terra na Bacia do Arroio da Ronda (Ponta Grossa - PR) e sua influência nos processos geomorfológicos

Meneguzzo, Paula Mariele 31 August 2009 (has links)
Made available in DSpace on 2017-07-21T18:13:40Z (GMT). No. of bitstreams: 1 Paula Meneguzzo.pdf: 4068196 bytes, checksum: ec0e731a285f1957b7a5b78260646b28 (MD5) Previous issue date: 2009-08-31 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This research had as main objective to assess the evolution of land use in the Arroio do Ronda’s Basin (Ponta Grossa - PR) and its influence on the geomorphological processes in the period 1980 to 2009. This time interval was divided into three periods: 1980-1989, 1990- 1999 and 2000-2009, and in each of these periods were identified geomorphological processes, which are developed on lands with different physical characteristics, and were present in different classes of land use. Some cases were more typical of uses associated with rural areas such as pipings that are associated with collapse. Other processes are prevailed in urban areas, such as the grooves. After the processes identification, using the concentration processes equation (CP), which results in concentration of processes /km². Thus, in each time interval the equation was applied, showing that the measure was the increase in urbanization, the amount of CP increased, indicating this phenomenon may influence considerably the geomorphological processes. The CP equation was also applied in some physical and environmental characteristics of the basin, such as lithology, slope and soils, which also indicated a greater concentration on certain classes. The interest in studying the land’s evolution use and influence in geomorphological processes, is linked to the growth of the urbanized area of Ponta Grossa in recent decades, which joined to the natural factors, which ultimately lead to areas of geoenvironmental’s risk, still little studied in the present and not yet received the due attention of local leaders. / A presente pesquisa teve como objetivo principal avaliar a evolução do uso da terra na bacia do Arroio da Ronda (Ponta Grossa - PR) e sua influência nos processos geomorfológicos, no período compreendido entre 1980 até 2009. Este intervalo temporal foi dividido em três: 1980-1989, 1990-1999 e 2000-2009, sendo que em cada um desses períodos foram identificados processos geomorfológicos, os quais desenvolveram-se em terrenos com características físicas diferenciadas, bem como estavam presentes em diferentes classes de uso da terra. Alguns processos, mostraram-se mais característicos de usos ligados à área rural, como os pipings que associam-se a colapsos. Outros predominavam em áreas urbanizadas, como é o caso dos sulcos. Após a identificação dos processos, utilizou-se a equação de concentração de processos (CP), a qual resulta na concentração de processos/km2. Assim, em cada intervalo temporal a equação foi aplicada, mostrando que à medida que houve o aumento da urbanização, o valor de CP cresceu, indicando que este fenômeno pode influenciar sobremaneira os processos geomorfológicos. A equação CP também foi aplicada em algumas características físico-ambientais da bacia, como litologia, declividade e solos, o que também indicou maior concentração sobre determinadas classes. O interesse em se estudar a evolução do uso da terra e a influência nos processos geomorfológicos, está ligada ao crescimento daárea urbanizada de Ponta Grossa nas últimas décadas, o que associou-se aos fatores naturais, que acabaram por originar as áreas de riscos geoambientais, as quais ainda são pouco estudadas na área em apreço e ainda não recebem a devida atenção dos dirigentes locais.
2

Assessing the impacts of riparian land use on gully development and sediment load : a case study of Nzhelele River Valley, Limpopo Province, South Africa

Mavhuru, Blessing January 915 (has links)
MENVSC / Department of Geography and Geo-Information Sciences / Human activities on land degradation have triggered several environmental problems especially in rural areas that are under developed. The main aim of this study is to analyse the contribution of different land uses to gully development and sediment load on the Nzhelele River Valley in the Limpopo Province. Data was collected using different methods such as observation, field data techniques and experiments. Satellite digital images, topographic maps, aerial photographs and the sediment load static model also assisted in determining how land use affects gully development and sediment load. For data analysis, the researcher used the following methods: Analysis of Variance (ANOVA), descriptive statistics, Pearson correlation coefficient and statistical correlation methods. The results of the research illustrates that high land use activities create negative changes especially in areas that are highly fragile and vulnerable. Distinct impact on land use change was observed within settlement area (9.6 %) within a period of 5 years. High correlation between soil organic matter and soil moisture (R=0.96) was observed. Furthermore a significant variation (p ≤ 0.6) between the soil organic matter and soil moisture was also observed. A very significant variation (p ≤ 0.003) was observed in bulk density and extreme significant variations (p ≤ 0.0001) were observed in organic matter and soil particle size. The sand mining and agricultural activities has contributed significantly to the amount of sediment load in the Nzhelele River. A high significant amount of total suspended sediment (55.3 %) and bed load (53.8 %) was observed within the agricultural area. The connection which associates the development of gullies to various land use activities determines the amount of sediment load. These results are consistent with other previous research and suggest that land use activities is likely to exacerbate the development of gullies and sediment load in the Nzhelele River Valley

Page generated in 0.0857 seconds