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In this paper discourse analysis on the Ethiopian National Action Program (NAP) to combat desertification is made. The aim is to describe how the overall image/picture of desertification, its causes, and effects and of possible solutions are presented in the NAP. The result of this analysis shows that the main cause of desertification is human activities mainly due to the poorly developed socio-economic situation in the dryland areas. It is indicated that an excessive dependency of the rural population on the natural resources, particularly land, is the major cause of land degradation and this deterioration of land is said to have been caused by the rapid population growth, overgrazing, forest clearing as well as past government and institutional failures. In addition it is indicated that the effect of desertification usually involves ecological changes that sap land of its ability to sustain agriculture and human habitation, therefore the most serious threat to human welfare. Desertification diminishes the ability of affected countries to produce food and consequently entail the reduction of regional and global food- producing potential with impacts on world food reserves and food trade. The solution given to mitigate desertification in Ethiopia is that the present strategies are intended to combat desertification, through different action programmes such as improving knowledge on drought and desertification, basic infrastructure, institutional organisations and capacity, awareness and participation as well as empowerment of women. The analysis also shows that priority was given to socio-economical aspect of the country not directly to combat desertification. It is suggested that in order to mitigate the land degradation, promotion of alternative livelihood is necessarily and this is reported to be achieved through industrialisation, rural credit programmes, intensification and diversification of agriculture, building awareness and access to information, enhancement of institutional organisations, participatory natural resource management, encouraging the private sector in involvement in forest development etc. Finally the analysis identifies different discourses, such as the survivalism, anthropocentrism, ecological modernisation, administrative- rationalism, economic rationalism and democratic pragmatism. Likewise the conflict that prevails between the discourses is discussed.

Call number: LD2668 .T4 1984 L39 / Master of Arts

Watersheds in the Southwest, particularly the San Simon Watershed in Arizona, have been experiencing degradation since the turn of the century through processes of erosion and vegetation change. Mitigation and management actions rely on long-term assessment of landcover change; however, traditional methods of ground assessment are time-consuming and specific to particular sites. Remote sensing techniques can be an alternative method to assess landcover change over extensive areas. Forage inventory surveys and historical monitoring data were assessed for utility in landcover change detection. The contemporary remotely-sensed classifications included 2001 SwReGAP data and a CART classification of 2010 Landsat TM data. The CART classification was aided by shrub cover analysis of NAIP aerial photography. It was found that 1930s Grazing inventories were compatible with contemporary satellite image classifications for large-scale landcover change detection.

Made available in DSpace on 2016-08-10T10:46:55Z (GMT). No. of bitstreams: 1 Goiacy Campos dos Santos Dunck.pdf: 4613309 bytes, checksum: 9b2f599a24f5631da91041fa5d1701d7 (MD5) Previous issue date: 2010-09-18 / The present monographic work entitled Nuclei of Brazilian north-eastern Desertification: Causes and Consequences; it is centered in the problematic one of the Environmental law, with respect to the set of specific Laws in world; wide and national level, protecting the viable public politics, in what it refers to the care and maintenance of the natural resources; but that, in the reality, such Laws are not accomplished, in sight of the capitalist society where we live and that cousin, over all, for the indiscriminate exploration of the happened resources of the ground, what cause, therefore, the increasing desertification in the whole world. They will be defined, in this scope, on concepts technician to the desertification; an ample vision of this process in the continents and the whole world; the verification of this problematic one in Brazil and, in the nuclei identified in the Northeast Region. The causes and consequence of the desertification, on social injunctions to the subject will be studied; in what it places in evidence, the real necessity of an ambient education in pedagogical level, as disciplines all in the institutions of education of the country and the whole world. The present research detaches the necessity of social confrontation of the related question, to place itself in practical the laws in the ambient sector, concurring for one better quality of life and maintenance of the life. / A presente dissertação, intitulada Núcleos de Desertificação no Nordeste Brasileiro: Causas e Consequências, está centrada na problemática do Direito Ambiental, no que concerne ao conjunto de Leis específicas em nível mundial e nacional, resguardando as políticas públicas viáveis, no que tange ao cuidado e manutenção dos recursos naturais; mas que, na realidade, tais Leis não são efetivadas, em vista da sociedade capitalista em que vivemos e que prima, sobretudo, pela exploração indiscriminada dos recursos advindos do solo, o que causa, portanto, a crescente desertificação em todo o mundo. Serão definidos, nesse âmbito, os conceitos técnicos ligados à desertificação, também será apresentada uma visão ampla desse processo e dessa problemática no Brasil, notadamente nos núcleos identificados na Região Nordeste. Serão estudadas as causas e as consequências da desertificação, as injunções sociais ligadas ao tema, evidenciando a real necessidade de uma educação ambiental em nível pedagógico, como disciplina nas instituições de ensino de todo o país e de todo o mundo. A pesquisa aqui apresentada destaca a necessidade de enfrentamento social da referida questão, para se colocar em prática as leis no setor ambiental, concorrendo para uma melhor qualidade de vida e manutenção da vida.

Northern Africa has experienced major shifts towards aridity and extensive C4 vegetation over the late Cenozoic, but due to a scarcity of spatially and temporally extensive paleoenvironmental records, the timing, patterns, and causes of these shifts are still under debate. Both long-term aridification and large amplitude orbital-scale climate variability have been recognized, with little understanding of how these two patterns relate to each other over time. African’s climate and environmental history of the last 7 Myr is of particular interest because hydrological and vegetation variability is considered the driving selection mechanism for human evolution. In addition, the age of the initiation of desert conditions in the modern Sahara desert, Earth’s largest warm desert and the largest source of dust to the modern atmosphere, is unknown. The stable isotope ratios of carbon and hydrogen in sedimentary plant leaf wax biomarker compounds have recently been shown to quantitatively track source vegetation photosynthetic pathways and the hydrogen isotope composition of plant source water, which is dominantly controlled by the amount of precipitation in Africa. These proxies have been applied to reconstruct long-term vegetation changes in East Africa and SW Africa over the last 14 Ma, as well as orbital-scale variability from various locations around the African continent, but they have not been extended further back in time or combined in tandem to robustly assess both long-term and orbital-scale climate and vegetation variability and how they relate to each other. In this thesis, I have utilized quantitative plant leaf wax stable isotope proxies to examine both orbital-scale and long-term changes in North African aridity and vegetation from a variety of regions over the last 25 Ma, with particular emphasis on the last 4.5 Ma. In Chapter 2, I investigated the evolution of hydrological and vegetation gradients from the equator to the sub-Sahara in NW Africa over the last 25 Myr using leaf wax stable isotopes at two marine sediment core locations, producing the longest existing leaf wax stable isotope record in Africa to my knowledge, and one of the longest such records globally. In this study I found that NW African environments were remarkably similar at both latitudes from 25 – 10 Ma, but at 10 Ma C4 vegetation abruptly expanded in the north, indicating sudden aridification in the Sahara region at that time. The hydrogen isotope record was stable long-term, with variability similar to that of known orbital-scale cyclicity in the Pliocene and Pleistocene, possibly suggesting that orbital-scale cyclicity or other factors obscured or were larger than any long-term changes in the hydrogen isotope ratio of precipitation. Saharan aridification at 10 Ma is consistent with climate model predictions of aridity due to the closure of the Tethys Seaway connection between the Indian Ocean and Mediterranean Sea near that time. The 10 Ma expansion in C4 vegetation is earlier than most other regions globally. To examine long-term changes in orbital-scale variability in the Eastern Sahara and Mediterranean Sea, I constructed a record of eastern Mediterranean sedimentary leaf wax carbon and hydrogen isotopes, leaf wax abundance, lignin biomarkers, and oxygen isotope ratios of planktonic foraminifera G. ruber during two 100-kyr periods of equal eccentricity near 3.0 and 1.7 Ma (Chapter 3). I found that precession-scale variability dominates the record during both periods, and Eastern Saharan precipitation and the vegetation assemblage, which was C4-dominated, do not change on average between the two periods. Chapter 4 extended the eastern Mediterranean record of Chapter 3 by sampling leaf wax stable isotopes in sapropel sediments (deposited during North African humid periods) at ~0.25 Myr resolution back to 4.5 Ma, placing the orbital-scale Chapter 3 results in long term context. I found that Eastern Saharan environments were persistently C4-dominated (>68%) throughout the entire interval, and that long-term hydrogen and carbon variability were similar in magnitude to orbital-scale cycles back to 4.5 Ma, strongly indicating that orbital-scale variability has been the dominant environmental control in NE Africa since the early Pliocene. This record contrasts sharply with observations of a transition from C3-C4 mixed vegetation to abundant C4 grasslands in East Africa over the same period of time. The results may suggest that long-term precipitation shifts did not occur in NE Africa since the Pliocene, or that the resolution of this approach is not sufficient to detect long-term shifts. It is likely that NW Africa also experienced similarly large hydrological variability over the same period of time, which may explain the unclear long-term hydrological signal in Chapter 2. The results emphasize that East Africa has not been representative of northern Africa as a whole since the Pliocene.

Esta pesquisa apresenta a aplicação de uma nova metodologia de medição de carreamento de solo, que foi utilizada durante o período de um ano, na área urbana de Paranavaí, no estado do Paraná. Teve como objetivo avaliar a fragilidade do solo e analisar os processos de erosão e arenização. Durante o seu desenvolvimento foram analisados principalmente os dados climáticos que envolveram desde as temperaturas médias anuais, índices de pluviosidade até direção e velocidade dos ventos de superfície. A partir da análise dos dados obtidos foram elaboradas cartas temáticas que permitiram um melhor entendimento do fenômeno da arenização, cerne deste trabalho. Uma série de fotos obtidas no campo auxiliou na análise e avaliação desses processos, gerando uma discussão de resultados que possibilitou tecer considerações sobre a recuperação de certas áreas onde ocorrem esses fenômenos. / This research aims to present the application of a new methodology of measurement of soil carrying over used during one-year term in the urban area of Paranavaí, in the state of Paraná-Brazil. Aiming to evaluate the soil fragility and analyzing the erosion processes and arenization, it was analyzed during its development, the climatic data from the average annual temperatures, pluviometric rates and even the direction and speed of the winds. Starting from the analysis point of the data collected, thematic letters were elaborated allowing a better comprehension of the arenization phenomenon, core of this work. A series of pictures were taken in field that helped us in the analysis and evaluation of these processes, arousing a discussion of the results, which let us talk about the recovery of certain areas where these phenomena occur.

FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / As bacias hidrogrÃficas sÃo Ãreas de relevÃncia significativa para estudos geogrÃficos por testemunharem as dinÃmicas, atuais e pretÃritas, da paisagem, por abrigarem vasta biodiversidade e por serem Ãreas preferencialmente de desenvolvimento das sociedades, contribuindo para atividades socioeconÃmicas e culturais. Devido a estas potencialidades, os usos feitos, em alguns casos, nÃo condizem com a capacidade de suporte, resultando em problemas ambientais. A desertificaÃÃo à a degradaÃÃo da qualidade dos recursos naturais e das condiÃÃes socioeconÃmicas nas terras secas. Esse processo de degradaÃÃo tem nÃveis de atuaÃÃo. As Ãreas do territÃrio brasileiro que possuem maiores nÃveis de degradaÃÃo sÃo denominadas de NÃcleos de DesertificaÃÃo. A presente pesquisa foi desenvolvida na sub-bacia hidrogrÃfica do riacho do Urubu-Mucuim que possui uma Ãrea de 310, 771kmÂ, no municÃpio de Arneiroz, localizado na porÃÃo sudoeste do Estado do CearÃ, no NÃcleo de DesertificaÃÃo dos SertÃes dos Inhamuns, tendo o objetivo de analisar a atuaÃÃo da desertificaÃÃo sobre esta sub-bacia. A metodologia utilizada foi a dos Sistemas Ambientais com a aplicaÃÃo dos Indicadores GeobiofÃsicos, que contribuÃram para entender o nÃvel de desertificaÃÃo existente. Para subsidiar esta anÃlise, tambÃm foram utilizadas como tÃcnicas o trabalho de campo, a aplicaÃÃo de entrevistas e a Cartografia, que contribuÃram na confecÃÃo dos mapas que possuem escalas de 1:100.000 e 1:150.000, as imagens de satÃlites utilizadas para o mapeamento foram Landsat 8 e Rapideye. A Ãrea estudada està susceptÃvel a atuaÃÃo da desertificaÃÃo, pode-se perceber que as caracterÃsticas geoambientais e os intensos usos feitos pelas comunidades contribuem com o quadro degradaÃÃo. PorÃm em algumas Ãreas os programas assistencialistas atenuam os processos de degradaÃÃo ambiental, havendo a necessidade de polÃticas de uso racional dos recursos naturais para mitigar e conviver com a problemÃtica da desertificaÃÃo. / Watersheds are areas of significant relevance to geographical studies by witnessing the dynamic, current and previous, landscape, for harboring vast biodiversity and areas are preferably development of societies, contributing to socioeconomic and cultural activities. Because of this potential, the uses made, in some cases, not consistent with the ability to support, resulting in environmental problems. Desertification is the degradation of the quality of natural resources and socioeconomic conditions in dry lands. This degradation process has performance levels. The areas of Brazil that have higher levels of degradation are called Nuclei of Desertification. This research was developed in the sub-basin of the Urubu-Mucuim stream which has an area of 310, 771km in the municipality of Arneiroz, located in the southwestern portion of the state of CearÃ, in Nuclei of Desertification SertÃes dos Inhamuns, with the aim of analyzing the performance of desertification on this sub-basin. The methodology used was the Environmental Systems with the application of Geobiofisicos indicators that helped to understand the level of existing desertification. To support this analysis, it was also used as technical field work, the application of interviews and Cartography, which contributed to the production of maps that have scales of 1: 100,000 and 1: 150,000, the satellite images used for mapping were Landsat 8 and RapidEye. The study area is likely the work of desertification; one can see that the geo-environmental characteristics and heavy duty applications made by communities contribute to the framework of degradation. However in some areas the welfare programs mitigate the environmental degradation processes, and there is thus a need for rational use of natural resources policies to mitigate and live with the problem of desertification.

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / A desertificaÃÃo constitui uma forma de degradaÃÃo e vem se tornando um dos mais graves problemas ambientais enfrentados pela humanidade. As Ãreas suscetÃveis à degradaÃÃo/desertificaÃÃo foram reconhecidas na ConvenÃÃo de Combate a DesertificaÃÃo (1977), sendo consideradas como tal aquelas situadas nas regiÃes de clima Ãrido, semi-Ãrido e sub-Ãmido seco. O Estado do Cearà tem a maior Ãrea proporcional suscetÃvel à desertificaÃÃo no Nordeste Brasileiro onde se destacam o municÃpio de IrauÃuba, a RegiÃo dos Inhamuns e a regiÃo do MÃdio e Baixo curso do vale do Rio Jaguaribe. Dentro da temÃtica abordada, o presente estudo considerou sete municÃpios que se encontram na regiÃo do MÃdio e Baixo curso do Vale do Jaguaribe: Alto Santo, Iracema, Jaguaretama, Jaguaribara, Jaguaribe, SÃo JoÃo do Jaguaribe e SolonÃpole. O objetivo geral do estudo foi avaliar, atravÃs de Ãndices, a Suscetibilidade Geoambiental Natural à DegradaÃÃo (ISGND) e a Suscetibilidade Geoambiental AntrÃpica a DegradaÃÃo (ISGAD) considerando, respectivamente, as caracterÃsticas geoambientais da Ãrea, e os impactos ambientais causados pelo sistema de uso da terra. Na pesquisa foi empregada uma adaptaÃÃo da metodologia usada por Beltrame (1994), que fundamenta o calculo do ISGND nas caracterÃsticas geoambientais e, para o ISGAD, na anÃlise da variaÃÃo temporal do Ãndice de Cobertura Vegetal. Esses Ãndices foram expressos numericamente atravÃs de uma fÃrmula descritiva fundamentado na EquaÃÃo da Reta computada atravÃs das ponderaÃÃes dos Ãndices de Erosividade, Erodibilidade, ClimÃtico e Classes de Relevo. Neste estudo o Ãndice de Cobertura Vegetal foi expresso pelos valores correspondentes do NDVI (Normalized Difference Vegetation Ãndex) calculado em imagens do satÃlite LANDSAT dos anos de 1986/89 e 2007. A aplicaÃÃo da metodologia nos permitiu obter como resultados a realizaÃÃo de um mapeamento cartogrÃfico da Ãrea do ISGND, dos nÃveis de cobertura vegetal, dos Ãndices de Erosividade, Erodibilidade, Ãndice ClimÃtico e Classes de Relevo e do ISGAD dos municÃpios considerados. / The desertification process constitutes itself in a form of degradation that became one of the serious environmental problems faced by Humanity. The areas that were susceptible to degradation/desertification were recognized by the Convention of Combated a Desertification (Desertification Combat Convention (1977) and were considered as such, those situated in the regions of arid, semi-arid and subhumid climate. The state of Cearà has most of the proportional area susceptible to desertification in the Brazilian Northeast with a preeminence of the areas of IrauÃuba, Inhamuns and midstream, lower stream of Jaguaribe river. This study considered seven municipalities that were located along the Vale of Jaguaribe in its mid and lower stream, the municipalities chosen were: Alto Santo, Iracema, Jaguaretama, Jaguaribara, Jaguaribe, SÃo JoÃo do Jaguaribe and SolonÃpole. The general objective of this research was to identify the conditioners of natural and socio-economical aspects of the process of desertification in this region, taking into account the characterization of environmental framework, observing its main potentialities (natural and socioeconomically) through the evaluation of impacts originated by the system of land use and evaluating the implication between the process of susceptibility to desertification and its impact over the socioeconomically characteristics of the area. The methodology used in the research had as its main fundamentation, the Beltrame focus (1994), that uses as its main parameter the standard analysis of vegetation through a comparison of satellite images betweens the years of 1986/89 and 2007. An application of the methodology allowed the realization of a general synthesis of the actual reality of the area regarding its problems, fragilities and potentialities of natural resources and socioeconomically aspects and to have a general vision of the degradation framework.

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / A desertificaÃÃo à um fenÃmeno que tem ocorrido em diversas partes do mundo, o que levou a OrganizaÃÃo das NaÃÃes Unidas - ONU a se preocupar com as suas causas e expansÃo determinando as Ãreas que estariam suscetÃveis ao processo. IrauÃuba, municÃpio integrante da MicrorregiÃo de Sobral à conhecido como um NÃcleo de DesertificaÃÃo no semi-Ãrido brasileiro. A MicrorregiÃo de Sobral destacase no Estado do Cearà por sua importÃncia histÃrica, educacional e econÃmica. Com a finalidade de avaliar a propagaÃÃo da desertificaÃÃo nessa Ãrea, adotou-se uma metodologia baseada no Ãndice ClimÃtico - IC, representado pelo Ãndice de Aridez - IA da UNEP e do Ãndice de Severidade do Clima - ISC, obtidos pelo balanÃo hÃdrico de Thornthwaiteâ55 utilizando os dados coletados em trinta e dois postos pluviomÃtricos da SUDENE na sÃrie histÃrica de 50 anos. O Ãndice de ErosÃo dos Solos â IES, representado pelo Potencial Natural de ErosÃo â IESN e pelo Potencial AntrÃpico de ErosÃo â IESA, foi determinado pelo uso da EquaÃÃo Universal de Perdas de Solos - EUPS, com os fatores erosividade da chuva, erodibilidade do solo, cobertura vegetal, componente topogrÃfico e prÃticas conservacionistas, fenÃmeno provocado por processos naturais e por atividades humanas. Os resultados permitem concluir que 80,10% do territÃrio està enquadrado em Ãreas suscetÃveis ao processo de desertificaÃÃo, demonstrado na Suscetibilidade Geoambiental Natural â SGN e na Suscetibilidade Geoambiental AntrÃpica â SGA, no qual os municÃpios de Sobral, MiraÃma e IrauÃuba apresentaram uma maior suscetibilidade ao fenÃmeno. / The desertificaÃÃo is a phenomenon that has occurred in dive rse parts of the world, what it took the ONU if to worry about its causes and expansion determining the areas that would be susceptible to the process. IrauÃuba, integrant city of the Sobralâs Microregion is known as a Nucleus of Desertification in the half-barren Brazilian. The Sobralâs Microregion is distinguished in the State of the Cearà for its historical, educational and economic importance. With the purpose to evaluate the propagation of the desertificaÃÃo in this area, a methodology based on the Climatic Index - IC was adopted, represented for the Index of Dryness - IA of the UNEP and the Index of Severity of Climate - ISC, gotten by Thornthwaite's method using the data collected in thirty and two rain ranks of the SUDENE in the historical series of 50 years. The Index of Erosion of Ground - IE S, represented for the Natural Potential of Erosion - IESN and for the Antropic Potential of Erosion - IESA, was determined by the use of the Universal Soil Loss Equation - EUPS, with the factors rain erosivity, soil erodibility, topographical component, vegetable cover and support practice, phenomenon caused for natural processes and activities human beings. The results allow to conclude that 80.10% of the territory are fit in susceptible areas to the process of desertification, demonstrated in Natural the Geoenvironmental Susceptibility - SGN and in the Antropic Geoenvironmental Susceptibility - SGA, in which the cities of Sobral, MiraÃma and IrauÃuba had presented a bigger susceptibility to the phenomenon.