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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.
11

The role of property rights for land degradation and land use conflicts / the case of Wetland in Gujranwala (Pakistan)

Akhter, Tasneem 11 March 2011 (has links)
Bodendegradation ist ein wachsendes Problem von Pakistan, die Biomasse Verlust verursacht und hat einen schlechten Einfluss auf die Wirtschaft des Landes. Nordöstlich von der Provinz Punjab, die berühmt für die Reisanbau ist, leidet auch mit diesem Problem. Zusammen mit einigen anderen Gründen, sind institutionelle Aufbau in den Regionen und der Landnutzungsänderungen der Hauptgründe für diesen Abbau. Obwohl das Land ist, die privaten Eigentümern, aber wegen der Störung der bestehenden Eigentumsrechte und die jüngste Stadterweiterung in der Region hat interfamiliären Konflikte zwischen Grundbesitzern im Zusammenhang mit Entfremdung Land provoziert. Diese Konflikte haben ein Potenzial von gefährden ländlichen Setup und der landwirtschaftlichen Produktion des Landes. Das Ziel der Studie ist es, diese Konflikte Ansatz, den Schwerpunkt auf die Notwendigkeit des institutionellen Wandels für die Nutzung von landwirtschaftlichen degradierten Flächen und mögliche Governance-Struktur für Land Umwandlung in Pakistan. Die Organe der Sustainability Framework von Hagedorn et al (2002) wird verwendet werden, und einige politische Empfehlungen gehen abgeleitet werden. / Land degradation is a growing problem of Pakistan, which causes biomass loss and has a bad effect on the economy of the country. Northeast of Punjab province, which is famous for the rice cultivation, is also suffering with this problem. Along with some other reasons, institutional setup in the regions and the land-use change are the main reasons of this degradation. Although the land is owned by private owners, but because of the malfunctioning of existing property rights and the recent urban expansion in region has provoked interfamily conflicts between landowners related to land alienation. These conflicts have a potential of jeopardising rural setup and agriculture production of the country. The aim of the study is to approach these conflicts, focus on the need of institutional change for the use of agricultural degraded lands and possible governance structure for land conversion in Pakistan. The Institutions of Sustainability Framework of Hagedorn et al (2002) will be employed and some policy recommendations are going to be derived
12

Furnitura multipla di servizi ecosistemici da culture energetiche poliennali / MULTIPLE ECOSYSTEM SERVICES PROVISION FROM PERENNIAL BIOENERGY CROPS / Multiple ecosystem services provision from perennial bioenergy crops

FERRARINI, ANDREA 17 March 2016 (has links)
La sfida nel 21esimo secolo è quella di fornire cibo e energia ad un mondo in continua crescita demografica e allo stesso tempo conservare l’ambiente. In questa tesi uno scenario alternativo di uso del suolo per la produzione di bioenergia è stato testato: le fasce tampone bioenergetiche. Considerate le problematiche ambientali legate al trilemma “cibo-energia-ambiente”, la struttura del Millennium Ecosystem Assessment sui servizi ecosistemici (SE) fornisce l’opportunità di esaminare l’impatto ambientale di questo nuovo scenario bioenergetico. In questa tesi ho mirato a determinare in che misura le colture bioenergetiche poliennali influenzino la fornitura multipla di SE quando coltivate come fasce tampone. Per raggiungere questo obiettivo, ho combinato una revisione sistematica della letteratura sui SE forniti da colture energetiche poliennali (CEP) con una prova sperimentale su fasce tampone bioenergetiche. Applicando una metodologia di attribuzione di punteggi agli impatti sui SE estratti dal materiale bibliografico raccolto, ho mostrato come coltivando le CEP lungo i margini dei campi coltivati esista una grande opportunità per sostenere la fornitura multipla di SE. La coltivazione delle CEP come fasce tampone adiacenti a campi agricoli può migliorare i SE di regolazione del clima, dell’acqua e della biodiversità, sostenere la salute del suolo e fornire biomassa dedicata alla produzione di bioenergia. Al contrario, la conversione di margini di campo di prati stabili ha mostrato un impatto netto negativo sulla fornitura multipla di SE. Tuttavia, due sono i principali svantaggi che sono stati individuati relativamente alla creazione e alla gestione delle fasce tampone bioenergetiche. Primo, diversi sono i fattori sito-specifici di tipo idro-pedologico lungo i margini dei campi che devono essere tenuti in considerazione poiché possono avere un impatto negativo sull’affrancamento delle colture e la loro produttività a medio-lungo termine. Secondo, riguardo la catena di approvvigionamento della biomassa, uno spazio di lavoro limitato per le macchine agricole è stato riconosciuto come principale inconveniente per le fasce tampone bioenergetiche rispetto alle CEP coltivate in pieno campo. Questo limite logistico di natura spaziale può inevitabilmente incrementare i tempi e le operazioni di taglio e raccolta della biomassa e quindi in ultima il consumo di combustili fossili. Grazie ad una prova sperimentale su fasce tampone bioenergetiche condotta in un terreno sabbioso-limoso con falda acquifera poco profonda contaminata da nitrati di origine agricola, si è dimostrato come fasce tampone coltivate con miscanto e salice siano in grado di intercettare e rimuovere i nitrati in falda (>60%) tanto quanto fasce tampone con specie avventizie. CEP come miscanto e salice, grazie ai loro apparati radicali profondi, hanno mostrato essere in grado di promuovere delle relazioni pianta-suolo-microorganismi lungo l’intero profilo del suolo utili ai fini ambientali delle fasce tampone bioenergetiche. Infatti, negli strati più profondi, una maggiore biomassa radicale ha portato le CEP a superare le specie avventizie in termini di rimozione biologica dei nitrati dal suolo e mitigazione potenziale dei gas serra. Inoltre, i risultati relativi alla produzione di biomassa e le asportazioni di N legata alla fase di raccolta hanno confermato ulteriormente come la coltivazione di CEP lungo i corsi d’acqua sia una strategia win-win: produzione di biomassa e protezione dell’ambiente. In conclusione, il potenziale rivelato dalle CEP in termini di fornitura multipla di SE suggerisce che la loro coltivazione, come elementi paesaggistici perenni in posizioni strategiche all'interno di paesaggio agricolo, è un'opzione promettente per promuovere l'intensificazione ecologicamente sostenibile degli agroecosistemi. / The 21st century will challenge agriculture to feed and fuel a growing world while conserving the environment. In this thesis an alternative bioenergy land use scenario to the conversion of marginal land has been tested: the bioenergy buffers. Given the environmental issues related to “food-energy-environment” trilemma, the Millennium Ecosystem Assessment framework on ES provides an opportunity to examine the environmental impacts of this new bioenergy land use scenario. In this thesis I aimed to determine to what extent do the perennial bioenergy crops affect the delivery of multiple ES when cultivated as bioenergy buffers. To reach this aim, I combined a systematic revision of literature on ES provided by perennial bioenergy crops with a field experiment on bioenergy buffers. Applying an impact scoring methodology to the effects on ES extracted from literature, I showed that, cultivating perennial bioenergy crops along field margins of former croplands offer a great opportunity to sustain the provision of multiple ES. The cultivation of perennial bioenergy crops on field margins can improve climate, biodiversity and water regulation services, sustain soil health and provide biomass for energetic purposes. On the contrary, grassland conversion showed a net negative impact on multiple ES provision. Nevertheless, I found two main shortcomings related to bioenergy buffers establishment and management. First, several site-specific factors along field margins must be taken into account, because they can affect crop establishment and buffers long-term productivity. Second, regarding to biomass supply chain, a limited working space for the farm machinery operations has been recognized as the main disadvantages of bioenergy buffers compared to large-scale bioenergy plantations. This spatial logistics constraint may inevitably increase harvest and collection operation times and fossil fuel consumption. Conducting a field experiment with bioenergy buffers in a nitrate-enriched shallow groundwater, I showed that miscanthus and willow buffers are able to efficiently intercept and remove from groundwater the incoming NO3-N as much as buffer strips with spontaneous species. Yet, due to their deep rooting systems, bioenergy buffers promote significant plant-microbial linkages along the soil profile. At deeper soil layers, a higher fine root biomass led perennial bioenergy crops to outperform patches of adventitious vegetation in terms of biological N removal from soil and belowground GHG mitigation potential. The results on biomass production and N removal via harvesting further confirmed that the cultivation of perennial bioenergy crops along watercourses is an effective win-win strategy: biomass production and protection of the environment. In conclusion, the revealed potential of perennial bioenergy crops on multiple ES provision implies that their cultivation as perennial landscape elements in strategic locations within landscape is a promising option to promote the ecological sustainable intensification of agroecosystems.
13

Aptidão agrícola, mudanças de usos dos solos, conflitos e impactos diretos e indiretos da expansão da cana-de-açúcar na região sudoeste goiano / Agricultural suitability, lands use changes, conflicts and direct and indirect impacts of sugar cane expansion in Goiás's sowth-west region

Trindade, Silas Pereira 30 March 2015 (has links)
Submitted by Erika Demachki (erikademachki@gmail.com) on 2015-12-10T16:21:28Z No. of bitstreams: 2 Tese - Silas Pereira Trindade - 2015.pdf: 6316279 bytes, checksum: 32da20157e5e99192704f93bc4a03beb (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Erika Demachki (erikademachki@gmail.com) on 2015-12-10T16:22:41Z (GMT) No. of bitstreams: 2 Tese - Silas Pereira Trindade - 2015.pdf: 6316279 bytes, checksum: 32da20157e5e99192704f93bc4a03beb (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2015-12-10T16:22:41Z (GMT). No. of bitstreams: 2 Tese - Silas Pereira Trindade - 2015.pdf: 6316279 bytes, checksum: 32da20157e5e99192704f93bc4a03beb (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2015-03-30 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / During the last 40 years, Cerrado in Goiás crossed to big changes of land use associated with the Green Revolution and the Agriculture Modernization. These modifications were based on grains production, cattle raising, in minor scale, sugar cane production. Goiás Sowth-west Planning Region (RPSG) was a great notability in this scenery that, since 1980 decade, because your elevated agricultural aptness, turned great objective of Agroindustrial complexes, grains and meat and, more recently, of sugar cane. Recently, the sugar cane sector retakes your expansion starting a new phase in 2004, extending from the same anterior surface from east, where more able soils dominated. Since this, a strong and fast expansion has been realized in this route, reaching the RPSG extreme west in 2008. The present thesis objective to recognize the special standard in these two sugar cane expansion phases in RPSG, between 1985 and 2013 and identify your relations with the lands use changes and with the agricultural aptness classes, for presenting the particular spatial standards of sugar cane expansion and having uses conflicts discrepancy indicators. It was used remote sensing and geoprocessing techniques, specially SIG, for the mapping of environmental characteristics, agricultural aptness and uses and soil uses conflicts, in historic succession of representative five years of use changes and sugar cane expansion; they were 1985 and 1995 in the first phase, and 2005, 2010 and 2013 in the second phase. The cartography results were submitted on statistic analyze ANOVA Fatorial and Principal Component Analyses (PCA). The results showed that the recent sugar cane expansion presented two spatial standards: the first, until 2005, in surfaces with more agricultural aptness, before with grains culture; the second, since 2005, in moderately or very fragile soils zones, able for natural pastures or recommended for flora e fauna conservation. It still revealed that sugar cane expansion reprises the agroexporting model, this time including the national market of ethanol consumption, however, in two successive itineraries: the first, that represents the itinerary resulting of spatial selectivity irradiated type, also practiced in Agricultural Frontier expansion (1970-80), looking for more able soils to cultivates with high technology level and taking advantage of structure, specially the logistic. The second, after 2005, that runs away this standard and goes to the extreme west of region, upon less able soils, in general sandy soils, with elevated erodibility, little fertility and cohesion, named fragile soils, with pasture and Cerrado’s reminders. It discusses that this process caused direct and indirect impacts in successions of covering/cane and pasture/cane, respectively, in consequence of deforestation, upon areas with moderated or elevated use discrepancy in respect to agricultural aptness. It concludes that the sugar cane expansion is occurring in RPSG for spatial irradiated selectivity, expanding upon the best lands (1960-80 in the east) and, before, 2005, for diffusion, in dispersed spots on direction to extreme west upon less able lands with fragile soils. In the first, the impacts were directs, by reconversion grains/cane; in the second, it were directs (like the first, added for pasture/cane and remaining/cane) and indirects (grains/pasture, remaining/pasture) also associated to the remaining deforestation. It was noted that the privation/insufficiency of regulatory marks for sugar cane expansion and planning and environmental govern in levels of state and region, favoring pressure upon natural resources and the installation of environmental (un)sustentability sceneries. / Durante os últimos 40 anos, o Cerrado Goiano passou por grandes mudanças de uso do solo associadas à Revolução Verde e à Modernização da Agricultura. Estas alterações foram baseadas na produção de grãos, pecuária de corte e, em menor escala, produção sucroalcooleira. Grande destaque deste cenário foi a Região de Planejamento do Sudoeste Goiano (RPSG) que, a partir da década de 1980, devido a sua elevada aptidão agrícola, tornou-se alvo grande dos Complexos Agroindustriais, de grãos e de carne e, mais recentemente, da cana-de-açúcar. Recentemente, o Setor Sucroalcooleiro retoma sua expansão iniciando uma nova fase em 2004, se estendendo a partir da mesma área anterior a leste, onde dominam solos mais aptos. Desde então vem implementando uma forte e rápida expansão nesse rumo atingindo o extremo oeste da RPSG em 2008. A presente tese objetiva reconhecer o padrão espacial dessas duas fases da expansão da cana-de-açúcar na RPSG, entre 1985 a 2013, e identificar suas relações com as mudanças de usos dos solos e as classes de aptidão agrícola, de modo a apresentar os padrões espaciais específicos da expansão canavieira e obter indicadores de discrepância e conflitos de usos. Utilizou-se técnicas de sensoriamento remoto e geoprocessamento, sobretudo SIG para o mapeamento do meio físico, da aptidão agrícola e dos usos e conflitos de uso do solo, em sucessão histórica de cinco anos representativos das mudanças de uso e da expansão da cana, sendo 1985 e 1995 da primeira fase e 2005, 2010 e 2013 da segunda. Os resultados cartográficos foram submetidos à análise estatística ANOVA Fatorial e Análise das Componentes Principais (PCA). Os resultados revelaram que a recente expansão da cana apresentou dois padrões espaciais: o primeiro (até 2005), nas áreas de maior aptidão agrícola, antes com cultivo de grãos; o segundo, desde 2005, nas áreas de solos moderadamente e muito frágeis, aptas para pastagens naturais e, ou conservação de flora e fauna. Ainda revelaram que a expansão canavieira reprisa o modelo agroexportador, desta vez incluindo o mercado nacional de consumo do etanol, porém em dois itinerários sucessivos: o primeiro representa o itinerário resultante de seletividade espacial do tipo irradiado, também praticado na expansão da Fronteira Agrícola (1970-80), buscando solos mais aptos às lavouras altamente tecnificadas, aproveitando a infraestrutura e, principalmente a logística da região. O segundo, de 2005 em diante, que foge desse padrão e segue rumo ao extremo oeste da região, sobre solos menos aptos, em geral arenosos, de elevada erodibilidade, baixa fertilidade e coesão, ditos frágeis, com pastagens e remanescentes de Cerrado. Discute-se que esse processo causa impactos diretos e indiretos nas sucessões de cobertura/cana e pastagem/cana, respectivamente, em consequência de desmatamento, sobre áreas de moderada a elevada discrepância de uso em relação à aptidão agrícola. Conclui-se que a expansão canavieira na RPSG vem ocorrendo por seletividade espacial de padrão irradiado, expandindo-se sobre as melhores terras (1960-80 no leste em 2004) e, após 2005, por difusão, em manchas dispersas em direção ao extremo oeste sobre terras menos aptas com solos frágeis. Nas primeiras os impactos foram diretos, por reconversão grãos/cana, nos segundos foram diretos (idem mais pastagens/cana e remanescentes/cana) e indiretos (grãos/pastagens, remanescentes/pastagens) associados também ao desmatamento de remanescentes. Nota-se a falta/insuficiência de marcos regulatórios para a expansão canavieira e de planejamento e governança ambiental nos níveis estadual e regional, favorecendo pressão sobre os recursos naturais e a instalação de cenários de insustentabilidade ambiental.
14

Une approche interdisciplinaire de la pertinence et de la faisabilité d'une co-gestion de la pêche récréative sur l'île d'Oléron : l'étrille, Necora puber (Linnaeus, 1767), comme modèle biologique / An interdisciplinary approach to assess the relevancy and feasibility of recreational fishing co-management on Oléron island : a target species, the velvet swimming crab (Necora puber, Linnaeus, 1767)

Coz, Richard 17 September 2013 (has links)
Parmi les nombreuses activités exercées sur les systèmes socio-écologiques littoraux, la pêche récréative a connu un essor important devenant ainsi un enjeu de développement durable. En France, les défauts de gouvernance de l'État dans la gestion du DPM invitent à s'interroger sur la pertinence et la faisabilité d'une co-gestion de ces pratiques de loisir. Ce paradigme, se voulant une alternative à une gestion top-down, prône la participation accrue des populations locales dans la gestion de l'environnement pour améliorer ses résultats. L'île d'Oléron ne déroge pas à ces constats qui sont renforcés par les modifications sociétales spécifiques aux territoires insulaires. Dans le cadre de recherches dont l'objet d'étude est une problématique sociétale, il est approprié de faire appel à une approche interdisciplinaire pour améliorer la pertinence des réponses apportées. Concernant la pêche à pied récréative à l'étrille, les résultats obtenus en biologie et en écologie mettent en évidence des caractéristiques qui semblent indiquer un faible impact potentiel à court comme à long termes de ces perturbations ponctuelles sur les populations locales. D'un point de vue sociétal, la pertinence d'une co-gestion de la pêche récréative est clairement établie par les nombreux conflits d'usages impliquant les pêcheurs récréatifs, le manque de moyens pour gérer la pratique et acquérir des données scientifiques, le manque de concertation, etc. La dynamique de développement du territoire oléronais et les initiatives locales à l'instar des conflits d'usages soutiennent l'idée de l'existence d'une « fenêtre politique » pouvant permettre la mise en place d'une co-gestion de la pratique dans les prochaines années, sous réserve d'une communication suffisante et d'une réelle volonté des acteurs concernés par la gestion de la pratique. / Among several other activities practice on coastal socio-ecological system, recreational fishing ones have significantly increased over the past few years, becoming an issue for sustainable development. In France, the weakness of states governance concerning DPM management, questions the relevancy and feasibility of a co-management policy for these leisure activities. This paradigm, constituting a good substitute for top-down management, recommends an increased participation of local populations for managing environments and improving their outcomes. Oléron Island is thus affected by these observations, which are intensified by societal changes distinguishing island territories. In the current research context, aiming at solving societal problematic, it is relevant to consider an interdisciplinary approach to provide relevant answers. Concerning recreational shellfish gathering targeting the velvet swimming crab, results in biology and ecology highlight some characteristics which should indicate a weak short and long terms potential impact of the disturbances affecting local populations. As regards to societal aspects, the relevancy of co-management is clearly demonstrated by several land-use conflicts, a lack of means to manage the practice and scientific data, the lack of consultation, etc. The territorial dynamic and local initiatives, as well as land-use conflicts, underline the existence of a “political window” which should allow the implementation of a co-management process for recreational fishing in the following years, subject to further efficient communication and a real desire from stakeholders concerned by the management of this practice.

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