Dissertations / Theses on the topic 'Agro-pastoral'

Mestrado em Engenharia do Ambiente - Instituto Superior de Agronomia - UL<br>The present dissertation aims at understanding how the future climate change scenarios may affect the production of grassland biomass in the montado agro-sylvo-pastoral system, by studying the effects of precipitation, aridity and topography (slope) in both the field, in different sites along a climatic gradient in Alentejo, and in greenhouse trials, using the seedbank collected at those sites. The impact of these three factors was studied independently, in order to understand the importance of each of them for biomass productivity and, consequently, determine the main driving factors. The results showed a stronger effect of precipitation during the growing season on biomass productivity, in both field and greenhouse trials, thus highlighting this factor, among the three studied, as the major driver of biomass response and consequently of future changes in the landscape of montado agro-sylvo-pastoral system in Alentejo. The comparison of field and greenhouse trial was also intended to study the seedbank ability to retain information regarding the past climate history of its site of origin – ‘memory’. Results showed that in greenhouse, regardless of the locations from where the soil samples were taken, the seed bank responded similarly in terms of biomass production, vegetation cover, species richness and flowering onset when subjected to similar favorable conditions in the greenhouse – regular and abundant watering.<br>N/A

Notre thèse porte sur la relation entre projet de développement et éthique de la solidarité. Nous faisons l’hypothèse que les deux concepts sont longtemps restés, dans l’analyse, comme dans la pratique, étrangers l’un à l’autre sur le continent africain et particulièrement au Togo, bien que les discours actuels sur le développement insistent sur la dimension humaine. Le réductionnisme économique qui caractérise la pensée économique depuis plusieurs siècles, en poussant à négliger d’autres dimensions essentielles du développement, est peut-être un des facteurs majeurs qui ont conduit à la fragilité voire à l’insuccès de tant de projets de développement sur le continent africain. Mais si le développement est un phénomène complexe, en raison de son caractère multidimensionnel, comment le repenser dans le contexte du Togo à partir de l’analyse d’une étude de situation, à savoir celle d’Avati ? L’ambition de cette étude est de contribuer à penser autrement les politiques de développement ; en particulier à partir de la notion de solidarité : celle-ci est assurément un concept aussi complexe que celui de développement, mais elle a l’avantage de mettre l’accent sur les conditions et les finalités du développement, c’est-à-dire d’en rappeler les dimensions anthropologique et éthique. Notre étude défend ainsi l’idée que le développement ne peut être un moyen de libération de l’homme que si la dignité de celui-ci lui est reconnue, tant dans sa dimension personnelle et interpersonnelle, que dans sa dimension collective<br>Our doctoral research aims at examining the relation between development projects and solidarity ethics. We assume that for a long time, the two concepts remained in their analysis as well as in practice, unfamiliar to each other on the African continent and particularly in Togo although the present discourses on development tend to emphasize human dimension. The economic reductionism which characterizes the economic thinking for several centuries while encouraging the neglect of other essential dimensions of development is perhaps one of the major factors which led to the fragility or even the failure of so many development projects on the African continent. But if development is a complex phenomenon because of its multidimensional aspect, we wonder how it can be reconsidered in the context of Togo from the analysis of a particular situation, namely Avati situation. The aim of this study is to contribute to thinking development policies differently, particularly from the concept of solidarity which is undoubtedly a concept as complex as that of development, but with its advantage of emphasizing the conditions and the aims of the development, i. E. To remind us of its anthropological and ethical dimensions. Thus, our study stands up for the idea that development can be a way of liberating human beings if only their dignity is being acknowledged, in a personal dimension as well as in an interpersonal dimension rather than in a collective dimension

European mountains have a long history of human presence and exploitation: during the last centuries, agro-pastoral activities determined a lowering of the treeline ecotone and shaped community composition of plants and animals, creating peculiar semi-natural habitats, on which high levels of biodiversity depend on. Currently, two contrasting phenomena are occurring in the rural areas: the abandonment of traditional farming systems in most of the areas and the overexploitation of some remaining pastures. We identified two different approaches to study these events by using insects as bio-indicators. The first one is multi-taxonomic approach, to assess the effects of grazing management on community composition and structure of macro-invertebrates at local scale. The second one is single species approach, the study of population dynamics, habitat preferences and dispersal ability of a target butterfly (included in Annex II of Habitats Directive) to define specific management plans designed for the species conservation. 1) In 2013, the Gran Paradiso National Park started a project in an overgrazed alpine pasture (2000 m a.s.l.), located on a steep stony slope, which was historically grazed but now improperly managed. Indeed, an excessive number of cattle and manure drain on the slope near to dairy barn, threaten ecological integrity of the area. To create an appropriate management plan for biodiversity conservation, a monitoring protocol has been developed to evaluate macro-invertebrates composition at different grazing levels. Four taxa were monitored (Coleoptera Scarabeidae, Coleoptera Carabidae, Orthoptera, Lepidoptera Rhopalocera) by means of semi-quantitative sampling techniques. At a local scale, we evaluated the taxa responses to different grazing pressures and we identified the most suitable indicator (functional) groups for the early detection of grazing impact. 2) Across its European range, the Euphydryas aurinia complex (Annex II of the Habitats Directive) includes a series of distinct populations. At least three taxa occur in Italy, each showing slight morphological differences and distinct eco-ethological features. All of them occupy habitats protected at European level (Habitat 6410, Molinia meadows; Habitat 6210, semi-natural dry grasslands on calcareous substrates; Habitat 4060, Alpine and boreal heaths), threatened by land use changes, which modify both structural and functional connectivity of habitat patches and the quality of the habitat itself. We collected data on adults flight by Mark Release and Recapture method in 15 patches for 2 populations, focusing on specimen density and distribution as a function of landscape and patches’ characteristics (topography and vegetation). We studied E. (a.) glaciegenita population in the mesophilous alpine grasslands (2000-2300 m) and E. (a.) provincialis in the mediterranean dry grasslands (700 m). As shown by results the two populations have different needs. For E. (a.) provincialis a wooded matrix is an unsuitable habitat. Nevertheless, the specimens aggregate in marginal areas of patches, near the edges where thermal conditions are probably more appropriate. The natural reforestation could increase mortality during inter-patch movements. The creation of corridors of suitable habitats between occupied patches and maintaining them by mowing, can definitely help the Mediterranean populations. Since E. (a.) glaciegenita is highly sedentary, changes in grassland management (e.g. increasing grazing regime) could seriously threaten this population, especially during the larval stage. The presence of a heterogeneous environment, also favoured by grazing, can surely support the Alpine populations at landscape, patch and microhabitat levels. The conservation of Alpine and Mediterranean populations may be a key to preserve all the members of the Euphydryas aurinia complex in Italy.

La matière organique (MO) remplit de multiples fonctions dans les systèmes agro-pastoraux ouest-africains. Or l'offre en ressource organique y diminue depuis plusieurs décennies. Afin d'estimer la viabilité d'un terroir agro-pastoral dans le sud du Sénégal, les bilans (stocks et flux) du carbone (C), de l'azote (N) et du phosphore (P ; assimilable seulement dans le sol et noté POD) y ont donc été établis.<br />Le terroir choisi était organisé en auréoles, avec une intensification croissante des pratiques de la périphérie (auréole de brousse) vers le village (champs de case).<br />Les stocks dans le système sol-plante étaient de 54,7 tC, 2,63 tN et 43,5 kgP ha-1 dans les jachères âgées, soit des croîts respectifs de 97, 29 et 251 % par rapport aux cultures de brousse (l'augmentation ayant lieu essentiellement dans la biomasse végétale). Les stocks mesurés dans le sol des champs de case étaient supérieurs à ceux des cultures de brousse, essentiellement dans l'horizon 0-10 cm. Cependant, la faible réponse globale des stocks de carbone des sols sableux à la jachère et à la fumure ne peut être interprétée qu'en réévaluant le rôle bio-thermodynamique joué par le carbone dans l'intégrité des agroécosystèmes locaux.<br />Les stocks moyens sur le terroir contrôlables par l'homme furent estimés à 29,7 tC, 1,52 tN and 28,6 kgP ha-1 en 1997. Le carbone était stocké surtout dans le sol. Elevage, récoltes et collecte de bois ont représenté respectivement 59, 27 et 14 % des prélèvements de carbone dans le terroir. Grâce à eux, des flux importants de carbone ont été établis vers les champs de case (3,8 tC ha-1 an-1), et les pertes minérales globales ont été estimées à 4 kgN et 1 kgP ha-1 an-1. Le terroir était donc proche de l'équilibre minéral.<br />Mais selon la dynamique démographique actuelle, la perte de carbone pourrait atteindre 0,38 tC ha-1 an-1, et la demande en carbone doubler durant les 30 prochaines années. Sans intensification des pratiques, ceci remettrait en cause la viabilité du système.

Bien caractérisée à l'échelle du Haouz, la région de Chichaoua-Imin'Tanout et de sa bordure est dotée d'une incontestable personnalité, physique et humaine. Cet ensemble (versants subatlasiques) qui forme un paysage divisé en trois faciès : le dir, la montagne et la plaine, apparait fort diversifié au niveau de l'occupation du sol. Certes, l'étagement de ses terroirs en amont, permet une vie agricole réduite par une irrigation traditionnelle et archaïque au fond des vallées. Cette vie est complète par une vocation pastorale en haute montagne et dans les vastes plaines. Cet étagement a toujours poussé à l'exploitation en complémentarité de ces différents compartiments physiques : plaine-montagne et piémont. Les cultures vivrières occupent une place importante dans le système de production. La population dans cette région, a depuis longtemps occupe le piémont et les vallées en faisant de ces lieux où jouxtent l'habitat et les cultures des zones de prédilection. Par contre la haute montagne et la plaine sont restées des lieux ou se déroulent une complémentarité amont-aval. La haute montagne est un lieu de parcours d'été et la plaine sert comme parcours d'hiver. Entre ces deux territoires, la naissance d'une polyculture sélective dans les vallées marque chaque paysage. En effet, le monde de vie est fait de contrastes, d'ambiguïtés, de paradoxes, mais aussi de valeurs sociales et culturelles ancestrales qui engendrent un équilibre fragile. Ces valeurs sont pourtant les bases de cette société qui vit dans cet espace, malgré les contraintes et les ressources insuffisantes. La micropropriété, l'exiguïté des parcelles et l'insuffisance des eaux d'irrigation ne permettent pas à la population d'investir plus dans les travaux du sol. Cette société a vocation agro-pastorale, commence à perdre son héritage de base, qui est la transhumance et l'arboriculture, sous l'effet de la sècheresse. C’est ainsi que le haut atlas occidental commence à vivre un développement d'autres secteurs tels que le commerce au détriment de l'économie de base (l'arboriculture et l'élevage). Or, vu le développement et les mutations qu'a connu la région récemment et qui ont engendré des phénomènes sociaux tel que l'émigration, il semble impératif pour l'état d'entreprendre une politique socio-economique globale et vigoureuse pour ces zones fragile comme les piémonts et les montagnes.

Malgre les potentialites naturelles qu'elle recele, tabarka a connu le declin economique le plus accentue. Les contraintes naturelles et socio-economiques s'opposent non seulement a la croissance agricole mais elles provoquent la rupture des ecosystemes. Cette perte de ressources naturelles (foret, sol, gibier, etc. . . ) est aggravee par l'expansion demographique. Pour refaire face a la situation, l'etat lance des projets agricoles dont les retombees locales sont modestes et des projets touristiques qui impliquent des consequences environnementales et marginalisent la petite paysannerie. L'auteur, apres avoir analyse les aspects socio-economiques et ecologiques, presente la these d'un developpement local, a la fois differencie et integre dans le cadre du systeme agro-sylvo-pastoral qui ameliore les conditions paysannes et sauvegarde les ressources forestieres. Il le demontre avec sensibilite et surtout avec objectivite<br>In spite of its natural potentialities, tobarka underwent the most severe economical drop. Natural and socio-economical restraints not only stand in the way of agricultural growth but cause the breaking of the ecosystems. This loss in natural resources (forests, soils, game, tec. ) is aggravated by demographic expansion. To meet this situation, the government launched agricultural projects with very modest local results and touristic projects entailing environmental effects and contributing to the leaving out apart of the small peasantry. The author, after analysing the ecological and socio-economical aspects, exposes the thesis of a local development, at the same time differentiated and integrated in the framework of the agro-sylvo-pastoral system, that would better the peasants' condition and preserve forests resources. The author demonstrates this with sensibility ans, above all, objectivity

La matiere organique (mo) remplit de multiples fonctions dans les systemes agro-pastoraux ouest-africains. Or l'offre en ressource organique y diminue depuis plusieurs decennies. Afin d'estimer la viabilite d'un terroir agro-pastoral dans le sud du senegal, les bilans (stocks et flux) du carbone (c), de l'azote (n) et du phosphore (p ; assimilable seulement dans le sol et note p o d) y ont donc ete etablis. Le terroir choisi etait organise en aureoles, avec une intensification croissante des pratiques de la peripherie (aureole de brousse) vers le village (champs de case). Les stocks dans le systeme sol-plante etaient de 54. 7 tc, 2. 63 tn et 43. 5 kgp ha 1 dans les jacheres agees, soit des croits respectifs de 97, 29 et 251% par rapport aux cultures de brousse (l'augmentation ayant lieu essentiellement dans la biomasse vegetale). Les stocks mesures dans le sol des champs de case etaient superieurs a ceux des cultures de brousse, essentiellement dans l'horizon 0-10 cm. Cependant, la faible reponse globale des stocks de carbone des sols sableux a la jachere et a la fumure ne peut etre interpretee qu'en reevaluant le role bio-thermodynamique joue par le carbone dans l'integrite des agroecosystemes locaux. Les stocks moyens sur le terroir controlables par l'homme furent estimes a 29. 7 tc, 1. 52 tn and 28. 6 kgp ha 1 en 1997. Le carbone etait stocke surtout dans le sol. Elevage, recoltes et collecte de bois ont represente respectivement 59, 27 et 14% des prelevements de carbone dans le terroir. Grace a eux, des flux importants de carbone ont ete etablis vers les champs de case (3. 8 tc ha 1 an 1), et les pertes minerales globales ont ete estimees a 4 kgn et 1 kgp ha 1 an 1. Le terroir etait donc proche de l'equilibre mineral. Mais selon la dynamique demographique actuelle, la perte de carbone pourrait atteindre 0. 38 tc ha 1 an 1, et la demande en carbone doubler durant les 30 prochaines annees. Sans intensification des pratiques, ceci remettrait en cause la viabilite du systeme.

Texte remanié de: Th. doct.--Sci. de l'environnement--Montpellier--ENGREF, 2001.<br>Mention parallèle de titre ou de responsabilité : Organic matter dynamics in mixed-farming systems of the West African savanna, a village case study from South Senegal. La couv. porte en plus : "environnement" Bibliogr. p. 209-235.

Botswana has the unusual reputation of being the only country in Southern Africa that has experienced consistently high rates of rapid economic growth since independence. Researchers emphasise this exceptionality, and many times the case of Botswana has been invoked to support the thesis that the feasibility of development in the Third World hinges on the existence of compatible political democratic structures and economic developmental efforts. The dynamics of internal development, however, have by and large been neglected, giving rise to undue and often misleading generalisations. This thesis is a critique of the Botswana postcolonial development model. It deploys a structural approach to dissect and analyse the economic development of Botswana in an historical perspective. Development literature is replete with macro-economic analyses that purport to illustrate how the Botswana state achieved optimal economic gains through prudent management of the economy and political liberalisation. However, there is, as yet, little else to indicate how the state has broadened the set of beneficiaries - especially amongst the peasantry. The present study demonstrates how agrarian transformation, stimulated by widespread borehole technology in the face of consistently available revenue from a booming mining sector, has influenced social relations of production and class differentiation in Botswana. It shows how the state ruthlessly exploited available revenue to sustain its hegemony - ensuring the preservation of a minority ruling class coalition and the marginalisation of well over two-thirds of the population in the process. The analysis thus demonstrates that Botswana, just like other mineral-rich African countries, has failed to direct development towards the rural sector. It essentially debunks the myth surrounding the exceptionality of the Botswana state.

I sistemi pastorali possono fornire una vasta gamma di servizi ecosistemici che vengono definiti dal Millennium Ecosystem Assessment come “i benefici che le persone ottengono dagli ecosistemi” e vengono classificati in quattro gruppi: i) supporto (necessari per la produzione di tutti gli altri servizi ecosistemici; es. produzione primaria), ii) approvvigionamento (prodotti forniti dagli ecosistemi; es. cibo, acqua), iii) regolazione (benefici ottenuti dalla regolazione dei processi ecosistemici; es. regolazione del clima) e iv) valori culturali (benefici non materiali che la popolazione ottiene dagli ecosistemi; es. esperienze estetiche). L’obiettivo principale della tesi è stato quello di utilizzare le analisi di alcuni dei più importanti servizi ecosistemici forniti dai sistemi agro-pastorali estensivi della regione Marche (Italia centrale), a supporto dei processi di co-progettazione di misure agro-climatico ambientali. Nel capitolo iniziale, attraverso un lavoro di review della letteratura scientifica, la tesi esamina le tendenze e gli approcci utilizzati nell’analisi di alcuni servizi ecosistemici forniti dai sistemi pastorali alla luce dei principi del Millennium Ecosystem Assessment. Successivamente, la tesi si concentra principalmente sull’analisi delle emissioni di alcuni gas ad effetto serra generati da diversi sistemi colturali e diverse gestioni: (i) respirazione del suolo di una prateria montana a dominanza di Bromus erectus sottoposta a diverse intensità di utilizzazione; (ii) emissioni di N2O in un sistema medica-frumento, con e senza l’applicazione di biochar, in un’area collinare. Nell’ultimo capitolo, la tesi analizza i processi di progettazione di misure agro-ambientali per la gestione di problematiche ambientali a scala territoriale in numerosi casi di studio. L’analisi della letteratura ha rivelato una generale confusione da parte dei portatori d’interesse relativamente al concetto di servizio ecosistemico. La biodiversità viene considerata un servizio ecosistemico di per sé e la visione antropocentrica dei servizi ecosistemici non è accettata o compresa. Dalla review emerge inoltre lo scarso utilizzo di un approccio multi-settoriale nell’analisi dei servizi ecosistemici, nonché quello di un’integrazione delle diverse conoscenze. In aggiunta, i servizi ecosistemici culturali risultano scarsamente studiati, nonostante siano considerati di grande importanza per i portatori d’interesse sia locali che generali e che, insieme ad altri importanti servizi ecosistemici, potrebbero favorire l’adozione di politiche e misure agro-ambientali. Dall’analisi della prateria a dominanza di Bromus erectus, non emerge nel breve periodo un impatto significativo dell’intensità di utilizzazione sulla respirazione del suolo né sulla produzione primaria. Nel sistema medica-frumento, l’analisi delle emissioni di N2O suggerisce che: i) la lavorazione posticipata in autunno può mitigare la perdita di azoto sottoforma di N2O; ii) gli effetti dell’applicazione del biochar dovrebbero essere analizzati nel lungo periodo per verificare i possibili effetti dell’invecchiamento del biochar, anche sulla produttività della coltura. I risultati ottenuti da questa ricerca potrebbero contribuire alla condivisione di conoscenze e alla formazione di una conoscenza ibrida che, insieme al cambio di ruolo dei portatori d’interesse del sistema, sono risultati elementi chiave del processo di co-progettazione di misure agro-climatico ambientali sito specifiche, condivise e a scala territoriale.<br>Grazing systems can provide a wide array of ecosystem services, defined by the Millennium Ecosystem Assessment as “the benefits that people obtain from ecosystems” and classified in four main groups: i) supporting (necessary for the production of all other ecosystem services; e.g. primary production), ii) provisioning (products obtained from ecosystems; e.g. food, fresh water), iii) regulating (benefits obtained from the regulation of ecosystem processes; e.g. climate regulation) and iv) cultural (non-material benefits people obtain from ecosystems; e.g. aesthetic experiences). The thesis aims to investigate some relevant ecosystem services provided by extensive agro-pastoral systems in the territory of the Marche region (central Italy) to support the co-design process of agrienvironmental climate measures. The thesis originates from a review paper that analyses the trends and approaches used in the analysis of relevant ecosystem services provided by grazing system, according to the framework principles of the Millennium Ecosystem Assessment. In a following step, the research focuses on the analysis of the greenhouse gases emissions under different cropping systems and management options: soil respiration from a Bromus erectus-dominated grassland under different mowing intensities in the uplands and N2O emissions in a alfalfa-wheat system with biochar application in the lowlands. A final chapter analyses the design process of agri-environmental measures at landscape scale implemented in several case studies. The literature review revealed a misunderstanding concerning the concept of ecosystem services among stakeholders. The biodiversity was considered an ecosystem services per se and the anthropocentric vision of the ecosystem services was not accepted or understood, moreover a lack of a multi-sectoral approach in the analysis of ecosystem services and the integration of different knowledge emerged. Furthermore, cultural ecosystem services were poorly studied despite being considered the most relevant for local and general stakeholders and with some other relevant services, could foster agri-environmental schemes. From the analysis of the soil respiration from a Bromus erectus-dominated grassland emerged that more intensive use did not significantly impact soil respiration and primary production on the short term. The analysis of the N2O emissions in the alfalfa-wheat system suggests that: i) postponed tillage in autumn may mitigate nitrogen losses as N2O after alfalfa termination; ii) the effects of biochar application on N2O emissions and crop productivity should be analysed in a long term perspective to verify the ‘biochar aging’. The results obtained from the research could feed the hybrid knowledge, that with shift of the stakeholder role in the system are key elements for the co-design process of site specific, shared and landscape agrienvironmental measures.

The question of agro/pastoral livelihoods adaptation is gaining attention in the rural development arena but little empirical evidence exists that has examined the performance and impact of diversified enterprises on agro/pastoral livelihoods and the environment in the ASAL, and on how to effectively support such initiatives. Additionally, there has been little evaluation of the type of behavioural patterns that agro/pastoral communities need to evolve in order to engage in such initiatives. This research study endeavours to bridge this knowledge-gap and assist the ASAL communities, NGOs, CBOs and government departments to understand the skills and resources required to develop climate-resilient, environmentally and economically sustainable bio-enterprises. This study examines the roles of bio-enterprise initiatives in enabling agro/pastoralists to develop more resilient livelihoods and incentivising positive community-led natural resource management and draws on different bio-enterprise initiatives located across the drylands of Kenya. In this study data was collected through interviews, focus group discussions and from secondary data. The analysis of four agro/pastoral bio-enterprise initiatives compares the level of success of specifically orientated development-funded support schemes. A more in-depth study was made of one of the initiatives, the BDP. Two surveys were made one year apart and secondary data was collected of the BDP impact. This highlighted the probable factors that influence the communities’ up-take of these bio-enterprises. Results show that this diversification requires stakeholders and support-actors to gain a greater understanding of business development approaches. Other factors such as capacity development to ensure production meets market standards, strong linkages with ethical commercial operators, access to trade-finance and ongoing mentoring proved to be the main drivers of success in these initiatives. The results show that the outputs of the BDP service-providing activities and the ethical trade facilities have been a major factor in the level of success achieved by the BDP. The main policy implications that this study has shown are: Agro/pastoralists realise that they can improve their resilience, food security and incomes by developing bio-enterprises. If conducted using conservation practices, this is an effective conservation and drought management tool. Communities do not possess the necessary skills and business acumen to diversify from traditional activities. Due to the lack of market knowledge, business acumen and technical skills many development and government instigated rural enterprise initiatives have failed. The commercial sector has strong transferable skills and will assist in developing bio-enterprises where commercial gains can be attained. This study has shown that where government, development and the private sector work in synergy projects are more socially, environmentally and economically successful. International standards and certification for sustainable harvesting of indigenous plant materials will effectively assist communities to manage their natural resource utilization and market their products more competitively. Women have shown that they have control over small-scale diversified activities and are able to choose how to use the revenue they have raised. Due to the orientation of agro/pastoralists to collective-action a wide ripple-effect can be seen from well-targeted business development assistance such as: mentoring, skills development, access to affordable trade finance/capital, improved market opportunities and value-addition.

La durabilité du fonctionnement des agro-écosystèmes et la gestion des services écosystémiques associés représente un des enjeux majeurs des sciences agronomiques et environnementales.Les systèmes agro-sylvo-pastoraux d'Afrique de l'Ouest (SASP-AO), étudiés depuis longtemps par la communauté scientifique, offrent un cas d’étude pertinent. La fertilité de ces agro-écosystèmes repose traditionnellement sur un taux de recyclage des nutriments très élevé au sein de l'agro-écosystème via la pratique de la jachère et des transferts de nutriments par les mouvements du bétail.Les SASP-AO sont soumis à des pressions socioéconomiques et démographiques fortes qui entrainent des modifications de leur organisation spatiotemporelle et des pratiques agricoles, notamment celles relatives à l'élevage.Dans cette thèse, nous nous sommes intéressés à l'impact de ces modifications sur la production végétale et animale à l'échelle de l'agro-écosystème.Nous avons choisi d’étudier les SASP en développant et analysant des modèles mathématiques de type méta-écosystème. Dans chacun des trois modèles proposés, nous avons cherché à représenter un SASP le plus simplement possible, en incluant les mécanismes biogéochimiques les plus importants (croissance des plantes, minéralisation, lessivage, dépositions…) et les pratiques agricoles d’intérêt. L’objectif était à la fois de comprendre comment ces mécanismes interagissent en fonction des pratiques et d’identifier des propriétés émergentes à l'échelle de l'agro-écosystème.Chacun des modèles a été développé pour étudier l'effet d'un nombre limité de pratiques agricoles portant sur l'organisation des composantes spatiales ou sur la connectivité entre les composantes spatiales.Dans la première partie de cette thèse, nous avons étudié l'influence de la structure des SASP-AO sur la production agricole de ces systèmes. Dans le modèle, quatre sous-systèmes interconnectés sont représentés : l’auréole de case, l’auréole de brousse, la savane et le village. Le modèle est de plus saisonnalisé, la dynamique de la saison sèche étant différente de celle de la saison humide. Avec ce modèle, nous avons étudié l’influence de trois leviers : (1) la durée de rotation et la durée des jachères dans les rotations, (2) la proportion de surface allouée aux différentes zones cultivées (case/brousse) de l'agro-écosystème et (3) la présence/absence du bétail dans l'agro-écosystème. Les résultats issus de ces travaux ont mis en évidence les services écosystémiques fournis par la savane, le rôle de du bétail comme « pompe à nutriments » des zones de pâturage vers les zones cultivées et les interactions entre les effets du bétail et les effets de la jachère sur les flux de nutriments. Dans la seconde partie, nous avons utilisé des outils issus de la théorie du contrôle afin de tenir compte de la variabilité dans le temps des pratiques agricoles. Nous avons ainsi montré qu'en faisant varier la pression d'herbivorie de manière adéquate, un gain supplémentaire de production est possible par rapport à une pression d'herbivorie constante pour une même quantité de nutriments transférée des pâturages vers les cultures.Dans la dernière partie de ce travail, l’optimisation multicritère du fonctionnement de l’agro-écosystème permet d’aborder la complexité des objectifs des SASP-AO comme système de production et de prendre en compte la gestion des risques dans ces systèmes. Nos résultats mettent en avant que les compromis entre production végétale et animale sont liés au choix des plantes cultivées. Nos résultats montrent également que les sources extérieures de nutriments permettent d’augmenter les productions, mais que leur efficience diminue quand leur quantité augmente.À l’interface entre écologie et agronomie, et grâce à l’utilisation conjointe d'outils issus d'autres disciplines, ces travaux de modélisation offrent de nouvelles perspectives pour l'optimisation de la production végétale et la gestion de la fertilité dans les SASP<br>The sustainability of agro-ecosystem functioning and the management of the associated ecosystem services is one of the major challenges of agronomic and environmental sciences. West African agro-sylvo-pastoral systems (WA-ASPS), which have been studied by the scientific community for a long time, offer an interesting case study. Traditionally, the fertility of these agro-ecosystems relies on a very high rate of nutrient recycling within the agro-ecosystem maintained by both fallowing and livestock induced nutrient transfers.Socio-economic and demographic pressures lead to major changes in the spatial and temporal organization of WA-ASPS and in the associated agricultural practices, including those related to livestock. In this thesis, we are interested in the impact of these changes on crop and meat production at the scale of the agro-ecosystem.We chose to study ASPS by developing and analyzing mathematical models using the ecological concept of meta-ecosystems. In each of the three models proposed, we tried to represent the ASPS as simply as possible, by including the key biogeochemical mechanisms (plant growth, mineralization, leaching, deposition...) and the agricultural practices of interest. The aim was both to understand how mechanisms interact according to the practices and to identify emerging properties at the scale of the agro-ecosystem.Each model was developed to study the effect of a limited number of agricultural practices on the organization of spatial components or on the connectivity between spatial components.In the first part of this work, we studied the influence of the structure of the WA-ASPS on the agricultural production of these systems. In the model, four interconnected subsystems are represented: the compound ring, the bush ring, the savanna and the dwellings. The year is decomposed in two seasons: the dry and the rainy seasons, the dynamic of the system being different for each season. With this model, we studied the influence of three driving-forces on the crop production: (1) the rotation duration and duration of fallows within rotations, (2) the proportion of the agro-ecosystem surface allocated to the different cropland areas (compound/bush) and (3) the presence/absence of livestock in the agro-ecosystem. The results of this work highlight the ecosystem services provided by the savanna, the role of livestock as a "nutrient pump" from rangeland to cropland and the interactions between livestock effects and fallow effects on nutrient fluxes. In the second part, we used tools provided by control theory to take into account the variability over time of agricultural practices. We showed that by varying the herbivory pressure over time in an appropriate way, an additional gain in production is possible (compared to the one obtained with a constant herbivory pressure) for the same amount of nutrients transferred from rangelands to croplands.In the last part of this work, the multi-criteria optimization of the functioning of the agro-ecosystem makes it possible to address the complexity of the objectives of WA-ASPS as a production system and to take into account risks management in these systems. Our results highlight that trade-offs between crop and animal production may be linked to the choice of crops. Our results also show that external sources of nutrients can lead to an increase in productions, but that their efficiency decreases as their quantity increases. At the interface between ecology and agronomy, and by using tools from other fields, this modeling work offers new perspectives for optimizing crop production and fertility management in ASPS

Comme l'a montré l'échec des PPBS et de la RCB dans les décennies soixante et soixante dix, l'action publique ne saurait se construire sur la rationalité instrumentale inspirée des sciences exactes. Toute politique publique est plutôt un construit social dans la mesure où elle résulte nécessairement du diptyque cognitivo-normatif : c'est la manière dont les acteurs dominant l'arène politique d'un secteur perçoivent la situation jugée problématique (dimension cognitive) qui structure l'action-réponse souhaitable (dimension normative). Aussi sera-t-elle forcément subjective et n'aura de pertinence qu'aussi longtemps que lesdits acteurs sauront convaincre les protagonistes de l'action, opération dont dépendra le plus ou moins de succès de la mise en œuvre. C'est dans cette perspective que s'inscrit ce travail. Après une mise au point sur les outils théoriques de l'analyse des politiques publiques, il montre que les référentiels des politiques de développement initiées au Burundi au fil du temps sont construits en Occident, donc en amont. Les actions induites se révèlent des diktats dès lors que le gouvernement et les bailleurs font l'impasse sur l'environnement socio-culturel des destinataires. Aussi s'explique leur insuccès, ce que nous montrons à partir d'un cas empirique : le projet agro-sylvo-pastoral de Rutana (Burundi). En conclusion, cette thèse suggère que l'action publique est le meilleur thermomètre de la légitimité de l'Etat (on le juge non à partir de ce qu'il dit être/faire mais de ce qu'il fait "in concreto") et s'avère une des meilleures méthodes de l'analyse de l'Etat.

Une agriculture éco-spirituelle peut-elle développer l’Afrique en cette ère de crise écologique ? Telle est la question à laquelle cette thèse répond à travers l’étude d’un projet de développement dont l’objectif est d’être pour le Bénin, un «vivier» de développement socio-économique, à partir de l’homme dont le profil est celui d’un «entrepreneur de type nouveau», «moralement équipé» et doté d’un important capital humain. Ce type d’homme est à «monter» de toutes les pièces du «savoir-être», du «savoir-faire» et du «savoir tout court» par une formation pratico-pratique, suivant le double principe pédagogique : «Apprends en faisant» et «Utilise ce que tu as pour avoir ce que tu veux». Apprendre à faire quoi ? Faire de l’agriculture un levier du décollage économique. Une agriculture écologique et entrepreneuriale, dont la méthode de production et de gestion, met en synergie la culture, l'élevage et la pisciculture d'une part, la production, la transformation et la commercialisation d’autre part et enfin, le social, l’économique et l’écologique, le tout dans une perspective plutôt théocentrique que cosmocentrique ou anthropocentrique<br>Can eco-spiritual agriculture develop Africa in this era of ecological crisis ? This present thesis tries to answer the above question through the study of Songhaï development Project whose objective is to be for Benin Republic a breeding ground for socio-economic development from the man which profile is “a new type of entrepreneur”, “morally equipped” endowed with an important human resources. This type of man is to be fully assembled with the “behavioural skills”, the “know-how”, and simply the “knowledge” by an in-depth practical training based on the double pedagogical principle : “Learn by doing” and “Use what you have to get what you need”. Learning to do what ? Transforming agriculture into the gear lever of economic progress. An ecological and entrepreneurial agriculture of which the productive and management methods take into account culture, breeding and fish farming in one hand, and production, transformation and marketing on the other, and finally its spiritual, social and economical dimensions

Le milieu montagnard andin constitue un systeme geographique complexe ou les composantes, naturelles et anthropiques, interferent a differentes echelles spatiales et temporelles dans la dynamique des bassins versants. Notre objectif consiste donc a comprendre l'organisation de cet espace, a identifier ses aptitudes et la nature de ses contraintes et enfin a connaitre ses tendances d'evolution. La fragilite naturelle de ce milieu est indeniable, principalement a cause de la raideur des pentes. La conjonction de plusieurs facteurs : pluies plus ou moins agressives, materiaux lithologiques instables et absence de couverture vegetale protectrice, contribuent largement a cette fragilite. Mais c'est le type et l'intensite de l'intervention anthropique qui jouent le role le plus important dans la reproduction et la survie de ce milieu. En vingt ans, avec la substitution de cultures traditionnelles, l'introduction de nouvelles varietes a hauts rendements et l'application de techniques modernes, l'agriculture du torbes a connu des changements significatifs. Mais ces changements n'ont pas ete radicaux dans toute la region, du fait qu'on trouve encore des noyaux d'une agriculture nettement traditionnelle. On a construit deux scenarios pour expliquer les futures tendances possibles d'evolution : le scenario de la continuite, qui nous semble le plus proche de la realite future du torbes, et le scenario ecologique, plus souhaitable, mais qui, dans les conditions economiques et politiques instables du pays, a peu de chances de se concretiser<br>The andean mountain environment consitutes a complex geographical system whose components, both natural and anthropic, interfere at different spatial and temporal levels in the dynamics of watershes. Our objectives consist, therefore, of understanding the organization of this environment, identifying its potential and its natural limitations, and finally, to know the tendencies of its future development. The natural fragility of this environment is undeniable, principally duc to the abruptness of the slopes. The accumulation of several factors : more or less violent rainfall, unstable lithic matter, and the absence of protective vegetation cover, contribute greatly to this fragility. But it is the type and the intensity of anthropic intervention that play the most important role in the reporduction and survival of this environment. Over twenty years, with the substitution of traditional crops, the introduction of new high yield varieties, and the adoption of modern technques, agriculture in the torbes region has undergone significant changes. But these cha nges have not been as radical throughout the whole region, duc to the subsistence of pockets of purely traditional agriculture. We have conceived two scenarios to explain the eventual tendencies of future development : the scenario of continuity, which scems to us to be the most probable future reality of torbes, and the ecological scenario, more desirable, but which, in the unstable economic and political conditions of the country, has little chance of realisation

Made available in DSpace on 2016-08-10T10:54:09Z (GMT). No. of bitstreams: 1 JULIANE VILELA FERREIRA SALOMAO.pdf: 21401363 bytes, checksum: 49ff8c7bb4789219260c2e907dc3497e (MD5) Previous issue date: 2013-04-01<br>In Brazil the environmental degradation has always been linked to the agro-pastoral development. This development generates relevant impacts to the natural biomes and one of the major issues are the venomous animal s accidents as these animals lose their natural habitats and end up establishing populations in crop areas or around urban areas looking for food and shelter. This study evaluated the incidence of venomous animal s accidents during the agro-pastoral expansion in the region of western Bahia between 2007 and 2011. The data collected at the DIRES of Barreiras, Ibotirama and Santa Maria da Vitória (western Bahia) indicated 5,649 venomous animals accidents, with 1,324 (23.4%) caused by venomous and nonvenomous snakes and 4,325 (76.5%) by venomous arthropods. By comparison with the national average we observed that the scorpion s accidents are more representative, with 96.1% of the cases in western Bahia, and the overall snake accidents are similar. Therefore, in the last 20 years there was an important increase in the local demography and land use which could lead to an increase in venomous animal s accidents. However, this situation occurred only with the venomous arthropods and is probably due to the land use with highly mechanized technology decreasing the rural human population and with a probable migration to urban areas together with their easy adaptation to this new habitat.<br>No Brasil a degradação ambiental sempre esteve muito ligada ao desenvolvimento da agropecuária. Este avanço gera impactos relevantes aos biomas naturais, e um dos agravos mais importantes são os acidentes por animais peçonhentos, uma vez que estes animais perdem seu habitat natural e acabam se estabelecendo em áreas de cultivo ou migram para áreas urbanas em busca de alimento e abrigo. O presente estudo avaliou a incidência de acidentes por animais peçonhentos durante a expansão agropastoril na região do oeste baiano entre 2007 e 2011. Os dados coletados nas DIRES de Barreiras, Ibotirama e Santa Maria da Vitória (oeste baiano) indicam 5.649 acidentes por animais peçonhentos, sendo 1.324 (23,4%) ocasionados por serpentes peçonhentas e não peçonhentas e 4.325 (76,5%) por artrópodes peçonhentos. Em comparação com a média nacional, observou-se que os acidentes por escorpiões são mais representativos, com 96,1% dos casos no oeste baiano, já os acidentes com serpentes venenosas apresentaram semelhança com os dados do país. Portanto nos últimos 20 anos houve um aumento importante na demografia e uso do solo na região do oeste baiano, que poderia esperar um aumento significativo no número de acidentes por animais peçonhentos. Entretanto, esta situação ocorreu apenas para os artrópodes peçonhentos, e provavelmente se deve à ocupação do solo com o uso de tecnologia e mecanização, diminuindo a mão de obra no campo e uma possível migração para as cidades, somado a sua facilidade de adaptação a esse novo habitat.

DUARTE, Rones da Mota. Natureza, Terra e Economia Agropastoril - SOURE (CE): 1798-1860. 2012. 154f. – Dissertação (Mestrado) – Universidade Federal do Ceará, Programa de Pós-graduação em História, Fortaleza (CE), 2012.<br>Submitted by Márcia Araújo (marcia_m_bezerra@yahoo.com.br) on 2013-10-10T16:35:45Z No. of bitstreams: 1 2012-DIS-RMDUARTE.pdf: 1468851 bytes, checksum: 1d69dbd779c72db952d322d4f604bb41 (MD5)<br>Approved for entry into archive by Márcia Araújo(marcia_m_bezerra@yahoo.com.br) on 2013-10-10T17:30:23Z (GMT) No. of bitstreams: 1 2012-DIS-RMDUARTE.pdf: 1468851 bytes, checksum: 1d69dbd779c72db952d322d4f604bb41 (MD5)<br>Made available in DSpace on 2013-10-10T17:30:23Z (GMT). No. of bitstreams: 1 2012-DIS-RMDUARTE.pdf: 1468851 bytes, checksum: 1d69dbd779c72db952d322d4f604bb41 (MD5) Previous issue date: 2012<br>This work seeks to understand the way of life of the farmers in Soure during the first 60 years of the nineteenth century, taking into account land access, agro-pastoral production and the relationship these people had with nature. First I shall consider the colonization process of the west coast of Ceará, which initiated the formation of an agro-pastoral zone destined for commercial purposes. To this end, I shall examine the first expeditions to be sent to this coast, and seek to identify, from the accounts left by Father Luis Figueira and Martins Soares Moreno, the landscape and natural features of the area found by the settlers. Conquest of the territory was later carried out by soldiers from the Fortress of Nossa Senhora da Assunção, who began to apply for land grants in the region. I therefore look at the social profile of those who received these grants, and the advance into indigenous lands that caused disputes between natives and settlers throughout the territory. I shall then look into the effects of the Land Law of 1850, which was intended to consolidate the agro-pastoral zone in this region, and from the land registry of the Parish of São José do Ribamar, and from post-mortem inventories, I shall identify forms of land access, size and location of properties, and the agrarian landscapes created up until 1860. Finally, I shall look at the agro-pastoral activities developed by these farmers, as well as their understanding of nature, as used in the quest for a better use of natural resources for agriculture activities, and the environmental impacts caused by planting techniques and the introduction of exotic plants into the ecosystems of Soure, which resulted in environmental changes and the creation of a new agrarian landscape.<br>Este trabalho procura compreender os modos de vida de produtores agrícolas em Soure nos primeiros sessenta anos do século XIX, levando-se em consideração o acesso a terra, a produção agropastoril e as relações desses sujeitos com a natureza. Inicialmente, estudo o processo de colonização do litoral oeste cearense que iniciou a formação de uma zona agropastoril com propósitos comerciais. Nesse sentido, analiso as primeiras expedições enviadas ao litoral cearense, buscando, a partir dos relatos deixados pelo padre Luís Figueira e Martins Soares Moreno, identificar as paisagens e as características naturais do território encontradas pelos colonizadores que passaram a solicitar terras nessa região, assim como o perfil social dos sesmeiros, e as disputas entre nativos e colonizadores pelo território. Em seguida analiso os efeitos da Lei de terras de 1850 para a consolidação da zona agropastoril nessa região, onde, a partir do livro de terras e dos inventários post-mortem, busco identificar as formas de acesso a terra, o tamanho das propriedades, sua localização e as paisagens agrárias constituídas até 1860. Por fim, estudo as atividades agropastoris desenvolvidas por esses produtores, assim como a leitura da natureza realizada pelos mesmos na busca pela melhor utilização dos recursos naturais para a atividade agrícola e os impactos ambientais provocados pelas técnicas de plantio e introdução de plantas exóticas aos ecossistemas de Soure que proporcionaram a criação de uma nova paisagem agrária.

Construction of the Karakoram Highway (KKH) has led to more rapid socio-economic change in areas close to highway than in more remote areas such as the Gilgit Ghizer Region (GGR) in Northern Pakistan. In the present study the aim was to compare the livestock enterprise in the developed region (i.e KKH) with the less developed area (i.e. GGR). A 2 x 3 factorial design was used with two geographical transects and three cropping zones and one village being studied within each cell. Nutritional inputs to, and productive outputs from, the livestock system, together with their interaction were investigated. Wheat straw (48%), lucerne (24%) and maize stover (13%) were the dominant feeds. Cereal crop residues and lucerne were main sources of energy and protein respectively. The main livestock species kept were cattle (51%), goats (31%), sheep (10%) and donkeys (8%). Overall, 65% of the herd was made up of non-productive animals. Feed sufficiency was 33% greater in the KKH transect (P < 0.05) and feed offered was 33% higher per unit liveweight in the KKH transect (P < 0.05). Stored feeds and herd weight per household were higher in the GGR transect (P < 0.05). Daily milk yield and calving rate were higher (P < 0.05) in the KKH (2.9 l/d and 0.82) compared with the GGR transect (2.3 l/d and 0.52). However proportions of fodder and cattle sold were higher (P < 0.05) in the GGR transect (16.5 % and 8%) than in the KKH transect (8.5% and <1). Overall, performance was higher in the KKH transect and this was related to herd size being better matched with feed resources. Larger herds in the GGR transect reduced animal performance but detrimental effects appeared to be partly masked by differences in the quality of summer pasture resources between transects.

Submitted by Cássia Santos (cassia.bcufg@gmail.com) on 2017-01-18T09:24:53Z No. of bitstreams: 2 Tese - Simone Marques Faria Lopes - 2016.pdf: 3883149 bytes, checksum: 92e37708f034204f2d69f88500561775 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5)<br>Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-01-18T10:32:46Z (GMT) No. of bitstreams: 2 Tese - Simone Marques Faria Lopes - 2016.pdf: 3883149 bytes, checksum: 92e37708f034204f2d69f88500561775 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5)<br>Made available in DSpace on 2017-01-18T10:32:46Z (GMT). No. of bitstreams: 2 Tese - Simone Marques Faria Lopes - 2016.pdf: 3883149 bytes, checksum: 92e37708f034204f2d69f88500561775 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2016-12-20<br>Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq<br>We start from the hypothesis that the land use model existent in Paraíso-GO creek and Cerrado/Cadunga-MG stream river basins has been providing significant changes in the water quality of these streams, which receive sediments and nutrients from natural and anthropic factors. In this sense, the general aim of this research is to diagnose the water quality in relation to the model of land use and physical characteristics of the basins. The methods used followed the procedures of the American Public Health Association (APHA), CONAMA legislation nº 357/2005 (surface water) and ordinance of the Ministry of Health 2914/2011 (drinking water). When comparing the geological aspects of the two basins, it was verified that they are differentiated by the presence of the unconsolidated sands in the upper part of the Paraíso creek. Regarding the soils, both are distinguished by the presence of Cambisols in the Paraíso creek, and are similar in relation to the presence of soils with hydromorphic characteristics. Studies of land use between 2005 and 2015 demonstrated the gradual disappearance of the Cerrado biome, mainly in the Cerrado/Cadunga river basin. The watershed region of the Paraíso creek presented greater erosive potential in formation areas of the Vale do Rio do Peixe, as well as the Cerrado/Cadunga stream. Heavy metals contents in those soils identified at different sampling points reveal occasional contamination, mainly related to land use. In general, the sediment results of Cerrado/Cadunga stream showed that the distribution of elements has as main contribution the urban area and the discharge of urban and industrial effluents in the drainage network, and for the soils, agro-pastoral activities. For the Paraíso creek basin, the greatest influence was linked to agricultural activities, especially sugarcane. Out of the heavy metals found in both basins analyzed, what demands greater attention, both in sediments and in soils, is cadmium. Regarding the framing of water bodies, it was verified that the Paraíso creek and the Cerrado/Cadunga stream were included in all the sampling campaigns in classes III and IV of CONAMA Resolution nº 357/2005, since the variables Phosphorus, Cadmium and Cupper showed higher values than those established by the abovementioned Resolution. According to the classification of the water bodies of both basins, they can be used for human supply, after conventional or advanced treatment, to irrigation, amateur fishing, recreation and also animal watering. In this sense, it was concluded that the land use presented in both basins, due to the use of agrochemicals, poses significant risks to water quality, as well as the release of domestic and industrial effluents, since the basins evaluated presented changes in the same parameters evaluated.<br>Partimos da hipótese de que o modelo de uso da terra, presente nas áreas das bacias hidrográficas ribeirão Paraíso-GO e córrego Cerrado/Cadunga-MG, vem proporcionando mudanças significativas na qualidade das águas das mesmas, as quais recebem sedimentos e nutrientes provenientes de fatores naturais e antrópicos. Neste sentido objetivo geral, diagnosticar a qualidade das águas em relação ao modelo de modelo de uso da terra e características físicas das bacias. Os métodos utilizados na pesquisa seguiram os procedimentos da American Public Health Association (APHA), legislação CONAMA nº 357/2005 (água superficial) e portaria do Ministério da Saúde 2914/2011 (água potável). Ao se comparar os aspectos geológicos das duas bacias, verificou-se que as mesmas se diferenciam pela presença das areias inconsolidadas na parte superior do ribeirão Paraíso. Em relação aos solos, ambas distinguem-se pela presença dos Cambissolos no ribeirão Paraíso e se assemelham em relação à presença de solos com características hidromórficas. Os estudos de uso da terra entre 2005 a 2015 demonstraram o desaparecimento gradativo do bioma Cerrado, principalmente na bacia do córrego Cerrado/Cadunga. A região da bacia hidrográfica do ribeirão Paraíso apresentou maior potencial erosivo nas áreas de formação Vale do Rio do Peixe, assim como córrego Cerrado/Cadunga. Os teores de metais pesados nos solos identificados nos diferentes pontos amostrais revelam contaminações pontuais, principalmente ligadas ao uso da terra. No geral, os resultados dos sedimentos do córrego Cerrado/Cadunga mostraram que a distribuição dos elementos tem como principal contribuição a área urbana e o lançamento efluentes domésticos e industriais na rede de drenagem, e para os solos, as atividades agropastoris. Para a bacia do ribeirão Paraíso, a maior influência esteve ligada às atividades agrícolas, com destaque para a cana-de-açúcar. Dos metais pesados encontrados em ambas as bacias analisadas, o que demanda uma maior atenção, tanto nos sedimentos quanto nos solos, é o cádmio. Em relação ao enquadramento dos corpos d’água, constatou-se que o ribeirão Paraíso e o córrego Cerrado/Cadunga se enquadraram em todas as campanhas amostrais nas classes III e IV da Resolução CONAMA nº 357/2005, pois as variáveis Fósforo, Cádmio e Cobre apresentaram valores superiores aos estabelecido pela referida Resolução. Conforme o enquadramento dos corpos hídricos de ambas as bacias, as mesmas podem ser utilizadas para abastecimento humano, após tratamento convencional ou avançado, à irrigação, pesca amadora, à recreação e, ainda, dessedentação de animais. Nesse sentido, concluiu-se que o uso da terra apresentado em ambas as bacias, em razão do uso de agroquímicos, oferecem riscos à qualidade da água, tanto quanto o lançamento de efluentes domésticos e industriais, uma vez que as bacias avaliadas apresentaram alterações nos mesmos parâmetros avaliados.

Cette thèse vise à reconstituer les dynamiques de végétation et des sols, ainsi que l’activité des feux depuis la dernière période glaciaire dans le Centre-Est de la France. L’objectif est plus particulièrement de déterminer la période à partir de laquelle les forçages anthropiques prennent le pas sur les forçages climatiques dans la dynamique des écosystèmes et à caractériser la nature et l’intensité des pratiques agro-pastorales qui accompagnent ce changement. Pour cela des analyses paléo-écologiques (palynologiques,micro-anthracologiques et géochimiques) ont été réalisées à partir de trois séquences sédimentaires lacustres du Sud-Jura et du Bas Dauphiné.Du Tardiglaciaire au début de l’Holocène, soit de 14700 à 9000 cal. BP, les évolutions des indicateurs paléo-écologiques apparaissent fortement corrélées aux oscillations climatiques régionales et globales. Jusqu’au milieu de l’Holocène, de 9000 à 5000 cal. BP environ, les données polliniques montrent un impact anthropique de faible ampleur sur la couverture forestière, qui n’engendre aucun changement significatif dans l’activité des feux et les dynamiques d’érosion. De plus, durant cette période,aucun changement climatique ne semble avoir été suffisamment intense ou durable pour engendrer des modifications remarquables des écosystèmes. A partir de 5000-4500 cal. BP, les dépôts sédimentaires enregistrent une augmentation de l’activité des feux liée à son utilisation comme outil de conquête par l’homme sur la forêt (essartage par exemple). Cette période correspond au passage d’un régime de feu sous « contrôle naturel » à un régime sous « contrôle anthropique ». Ce n’est que plus tardivement, vers 2300 cal BP (second âge du Fer), que les activités agropastorales deviennent assez intenses pour modifier durablement la couverture végétale et générer une érosion sans précédent des sols. Le régime du feu change à nouveau, suite à une modification de son usage ; il devient alors un outil de gestion des espaces agropastoraux et les analyses attestent de son rôle capital dans les dynamiques de transformation et d’évolution des paysages. La pression anthropique devient permanente et un seuil important semble avoir été franchi dans l’histoire locale des agro-systèmes.Au sein de cette période très anthropisée, trois grandes périodes se détachent : l’âge du Fer jusqu’à la période romaine, le Moyen Age et l’époque moderne se distinguent par leurs types de pratiques agro-pastorales et leurs effets sur l’érosion des sols<br>This thesis aims to reconstruct vegetation and soil dynamics, as well as ire activity variabilityin the East-central part of France since the Last-glacial period (ca. 15000 yr). The objective is mostparticularly to disentangle the role of climate and anthropogenic forcing factors in ecosystems dynamics.Actually, the problematic concerns the switch from a climatic- to anthropogenic-driven ecosystemsand the study of agro-pastoral practices impact which leads to an ecological trajectory change. Thus,palaeoecological analysis (pollen, geochemical and micro-anthracological) were performed from threelake sediment records of Southern Jura Mountains and Bas Dauphiné areas.During the Late-glacial and the early Holocene period (14700 to 9000 cal. BP), palaeoecologicalchanges appear strongly correlated to regional and global climate oscillations. Until the mid-Holocene(9000 to 5000 cal BP), pollen analysis record a small-scale human impact on forest cover and nosigniicant changes in ire activity and soil erosion. Moreover, none climate change has been suficientlyintense or sustainable to generate remarkable modiications of the ecosystem. From 5000-4500 cal. BP,the sedimentary deposits recorded an increase in ire activity related to its use as a clearing tool. Thisperiod corresponds to the switch from a natural to an anthropogenic control on ires activity.It was only from ca. 2300 cal BP (Late Iron Age) that agro-pastoral activities become enoughintense to induce sustainable change in the vegetation cover and generate unprecedented erosion of soils.In parallel, the ire use changed and it became a tool for the management of agro-pastoral areas. Therefore,the human impact can be considered as permanent and a tipping point has been reached in the history oflandscape shaping. However, three main periods: Iron Age to roman period, medieval and modern timescan be distinguished through the development of agro-pastoral practices and their impact on ecosystems,most particularly on soil erosion

L'objectif de cette thèse est de montrer la pertinence de l'analyse de la dynamique du paysage agro-forestier et lacustre du bassin hydrologique de Patzcuaro (dans l'état mexicain de Michoacán) conçue comme un outil théorique et méthodologique pour approcher l'état du développement agro-pastoral et son impact sur le couvert forestier et le milieu. Cette analyse a été faite selon une approche systémique et structurelle, synchronique et diachronique afin d'appréhender les changements dans l'espace et dans le temps du paysage dudit bassin hydrologique. A ces fins, on a utilisé les données statistiques des recensements agro-forestiers, les données spatiales livrées par la cartographie thématique régionale et les données numériques enregistrées par les capteurs embarqués sur les satellites d'observation de la terre. Dans cette thèse, des données analogiques et numériques ont été systématiquement exploitées à l'aide des traitements statistiques multivariés, de logiciels de traitement d'images et d'algorithmes adaptes à la qualité des données et aux objectifs de cette recherche. Grâce à cette démarche méthodologique il a été possible d'observer l'ensemble des variations de l'utilisation de l'espace et d'établir une typologie spatio-temporelle du paysage.

Dans le cadre du changement climatique global, mieux comprendre les interactions Hommes/Environnement/Climat au sud-ouest du Groenland est aujourd’hui un enjeu majeur pour développer des stratégies d’adaptation tout en préservant au mieux les écosystèmes. Pour cela, une approche rétrospective a été réalisée sur trois séquences lacustres retraçant l’histoire paléo-environnementale sur les 5000 derniers millénaires. Le lac d’Igaliku (N61°00’22’’, O45°26’28’’), situé à 2 km de la capitale épiscopale médiévale au cœur de la région agricole groenlandaise, a une sédimentation principalement influencée par les activités anthropiques. Un inventaire moléculaire complet a été réalisé sur cette séquence pour caractériser les dynamiques agropastorales passées et leurs impacts sur les écosystèmes. Les biomarqueurs fécaux identifié ont notamment permis de mettre en évidence deux phases agropastorales majeures (la période d’occupation viking et la période récente) séparées par le Petit Âge Glaciaire (PAG), pratiquant un élevage prédominant d’ovins. Les biomarqueurs moléculaires de végétation (n-alcanes, acétates de triterpényles) couplées à des données palynologiques montrent une réduction du couvert arbustif au cours de ces deux phases. Par ailleurs, les biomarqueurs d’érosion des sols (TTHCs) couplées aux données sédimentaires indiquent une érosion drastique qu’autour des années 1980 lors de la création de parcelles de fourrage par labour mécanisé. De même, ce n’est que sur le dernier siècle qu’une altération de l’état trophique du lac d’Igaliku associée à des pratiques de fertilisation des parcelles de fourrage est observée avec une augmentation des chaines courtes d’n-alcanes et plus particulièrement des diatomées mésotrophes. Les lacs de Qallimiut (N60°43’27’’, O45°23’12’’) et de Little Kangerluluup (N60°38’32’’, O45°38’11’’), situés en contexte faiblement anthropisé, sont alimentés par des tributaires à forte variabilité hydrologique. Ils correspondent à des systèmes sédimentaires dominés par des apports clastiques sous contrôle climatique dominant. Afin d’améliorer la résolution spatiale et temporelle des changements climatiques holocènes dans cette région, une étude sédimentaire multi-paramètre a été réalisée sur ces deux sites. Des analyses pétrophysiques, granulométriques, minéralogiques et géochimiques ont mis en évidence des niveaux de crues fréquents au cours des épisodes froids et humides comme la transition Milieu/Fin de l’Holocène (ca. 2500 BC), la transition Sub-boréal/Sub-atlantique (ca. 700 BC) et le PAG (entre ca. 1300 AD et ca. 1900 AD), synchrones à des périodes de minimas solaires. Ces épisodes de détériorations climatiques ont particulièrement influencé les sociétés humaines successives installées dès ca. 2500 BC au Groenland. Un maximum de fréquence de crues et une baisse drastique des températures sont notamment enregistrés pendant le PAG, indiquant qu’il s’agit de l’épisode le plus froid enregistré au sud du Groenland au cours de la seconde moitié de l’Holocène, responsable en grande partie de l’abandon de ces terres par les agriculteurs vikings au milieu du XVème siècle<br>In the current context of global change, understanding the interactions between Human/Environment/Climate is necessary to develop adaptive strategies and preserve ecosystems. A retrospective approach is therefore realized in three lacustrine cores to reconstruct the paleo-environmental history during the last five millennia. Lake Igaliku (N61°00’22’’, W45°26’28’’), located at 2km from the medieval episcopal cathedral in the historical farming center, has a sedimentation mainly driven by anthropogenic activities. A complete molecular inventory has been made on this sequence to characterize past agropastoral dynamics and their impacts on south Greenlandic ecosystems. The identified fecal biomarkers revealed two agropastoral phases, during the Norse settlement and recently, separated by the Little Ice Age (LIA) and mainly characterized by sheep breeding. Vegetation molecular biomarkers (n-alkanes, triterpenyl acetates) and palynological data showed a reduction of trees and shrubs cover during these two periods especially. Erosion biomarkers (TTHCs) and sedimentological data identified only one drastic erosion in the 1980s synchronous with the mechanized creation of fodder parcels. Moreover, an eutrophication of the lake waters was recorded with short chain length n-alkanes and mesotrophic diatoms. Lake Qallimiut (N60°43’27’’, W45°23’12’’) and Little Kangerluluup (N60°38’32’’, W45°38’11’’), less impacted by anthropogenic activities, are fed by major streams influenced by hydrological variations. Their sedimentation is therefore mainly driven by climate changes. To improve the temporal and spatial resolution of climate changes during the Holocene, a multi-proxy sedimentological study was made on these two sites. Petrophysical, mineralogical and geochemical analyses have identified flood events especially occurring during cooler and wetter periods such as the Middle to Late Holocene transition (ca. 2500 BC), the Sub-boreal/Sub-atlantic transition (ca. 700 BC) and the LIA (between ca. AD 1300 et ca. AD 1900). These climate pejorations have impacted local human societies. For example, during the LIA, a maximum of flood events and drop of temperatures are recorded, partly responsible of the Norse demise

The Fulbe Jelgobe, like many other Sahelian pastoral groups, are becoming increasingly vulnerable to chronic food insecurity. They live in a landscape that exhibits a complex patchiness and extremely variable rainfall patterns. When their food security is threatened, the Fulbe Jelgobe act skillfully on the basis of local knowledge in employing a complex array of coping responses that seek to meet immediate food needs while preserving a base for future livelihood activity. These responses involve the manipulation of household asset portfolios, modifying household consumption patterns, access to common property resources and the activation of networks of social relationships. The reinforcement or enhancement of such responses is a credible means of improving food security. This thesis reports on an attempt to apply action research amongst the Fulbe Jelgobe in Northern Burkina Faso, focusing on case studies of action research in two Fulbe communities. These communities provide the context for understanding a particular food insecurity situation by taking action to improve it. The process was co-designed and co-managed by action research groups formed in both locations. These groups included diverse stakeholders who cooperated with me in learning how to contextualise the Participatory Action Research process to improving local food security. A third, general action research process is underpinned by ten years of previous experience in the area and ethnographic research that provides an understanding of the context for Fulbe subsistence strategies. While the process of participatory Action Research is perceived to be useful in such vulnerable livelihood contexts, the participatory process itself is viewed as problematic and frequently more partisan than many adherents to the process would accept. There is a complex web of motivations driving local stakeholders participation. Rather than extended dialogue aimed at achieving consensus, as many popular participatory approaches envisage, it is a matter of continually re-negotiating cooperation among stakeholders with diverse interests and capabilities in order to secure continuing participation in a heuristic learning process. Treating Fulbe agro-pastoralism holistically as social praxis, a locally managed Participatory Action Research process facilitated improved food security by reinforcing coping options and enhancing local organisational capacity to interface with development organisations. Participatory Action Research provided a framework for the design and management of food-for-work programs aimed at developing an infrastructure for dry-season gardening in both locations. The action research group in one location became the management committee of an association of some 80 people that was formally registered with the government under the name of Dewral. This association, which is still functioning, facilitates the cultivation of 25 hectares of lakeside gardens. These gardens are an important addition to the members' mix of food procuring activities.

Les pelouses seches calcicoles du parc naturel regional du vercors representent un enjeu de conservation majeur dans les prealpes du sud, en raison d'une diminution de leur utilisation traditionnelle par les systemes d'elevage extensif. Le principal objectif de ce travail est la construction d'un modele multivarie de leur dynamique sous l'influence des conditions d'habitat (stress) et des modes de gestion (perturbations). La premiere partie analyse leurs influences respectives, combinees, et leurs interactions sur la composition floristique, par analyse canonique des correspondances (acc). L'effet separe de la lithologie est le plus determinant, expliquant 12% de la variabilite floristique, tandis que le meilleur modele est obtenu avec l'effet cumule des perturbations (frequence d'entretien mecanique x intensite de paturage) et de la lithologie (24%). Des groupes fonctionnels d'especes avec les memes traits biologiques et les memes reponses aux facteurs agro-ecologiques sont identifies par une analyse d'ordination a 3 tableaux (analyse rlq). La seconde partie traite de l'utilisation du modele multivarie pour evaluer les effets de la gestion conservatoire et de la restauration experimentale sur la richesse specifique, la rarete des especes et leur amplitude de niche sur les gradients agro-ecologiques. Les assemblages d'orchidees, especes cibles pour la gestion conservatoire, montrent des reponses complexes aux modes de gestion, dependant des traits biologiques des especes. Enfin, les resultats d'une experience de 6 ans de restauration de 4 pelouses par debroussaillement et paturage montrent que la richesse specifique et le nombre d'annuelles et d'especes rares ont augmente, avec des maxima atteints 3 a 4 ans apres debroussaillement. Le maintien ou la restauration de pratiques agro-pastorales extensives (combinaison de paturage et d'entretien mecanique pluri-annuel), parait donc indispensable pour conserver a long terme les pelouses calcicoles du vercors.

Thesis (M.S.)--University of Wisconsin--Madison, 2006.<br>Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 73-77).

The aim of the study was to develop strategies to reduce the unmet need for modern contraception among agro-pastoral women. The objectives of the study were to determine the prevalence of unmet need for modern contraception, determine the factors associated with unmet need for modern contraception, and explore the barriers that hindered agro-pastoral women from using modern contraception. A mixed-method research design was used to conduct the study. Data were collected from agro-pastoral women and family planning service providers. Questionnaire and individual in-depth interviews were used to collect the data. The validity and reliability of the quantitative data and trustworthiness of the qualitative data were ensured. Use of standard data collection tools, employing method and data triangulation, and documenting all the procedures of data collection and analysis were among the ways employed to do so The quantitative data were analysed using simple descriptive statistics and multivariate logistic regression. Thematic analysis was employed to analyse the qualitative data. Ethical principles of research such as beneficence, justice, informed consent, respect for persons, privacy and confidentiality and scientific integrity were considered to conduct the study. The study revealed an unmet need of 29.2% (n=112) for modern contraception among agro-pastoral women. The unmet need for birth spacing constituted 21.1% (n=81), whereas the unmet need for birth limiting was 8.1% (n=31). The age of the women, the number of living children, knowledge of modern contraceptive methods, and knowledge of FP service centres were found to be associated with women‘s unmet need for modern contraception. Lack of time and money, lack of knowledge about modern contraception, and fear of side effects were the major individual-level barriers. There were also culture-related factors such as the need for many children that hindered agro-pastoral women from using modern contraception. Moreover, the study disclosed that religious unacceptability and husband‘s and relatives‘ opposition were also among the mentioned barriers. The quality of FP service provision in terms of the competence and behaviour of health service providers, unavailability and inaccessibility of FP service, were also indicated as barriers. The findings informed the development of strategies to reduce agro-pastoral women‘s unmet needs for modern contraception in Eastern Ethiopia. The study further recommended that the health bureaus of the region, zone and district collaborate in ensuring that agro-pastoral women realise the significance of the provision of accessible, equitable, quality modern contraception. It is also essential to equip health facilities with qualified health service providers and necessary facilities. Religious leaders should be involved in disseminating vital, relevant and empowering FP information.<br>Health Studies<br>Ph. D. (Public Health)

During the months of April through July 1991 and June through July and 1992, a study was conducted to describe and compare the primary factors that affect management practices in two ecological agro—pastoral communities (Kasikeu: eco—zone IV and Mtito-Andei: eco-zone V) in Makueni district of Kenya. Sample families were chosen from Kasikeu (n=32) and Mtito Andei (n=31). A questionnaire was used for filling in the information as perceived and given by the respondents. Family heads were the interviewees but where they were absent, wives or resident sons represented them. The agro-pastoralists of Kasikeu and Mtito-Andei belong to a major bantu tribe called Akamba and generally have the same traditional and cultural background. The two communities therefore generally practised similar farm production activ ities regardless of their land ecological potential. The two communities were also affected more or less similarly by factors such as human population pressure, intro duction of a cash economy, education and amenities associated with sedentarization. Generally these factors have caused the agro-pastoralists to adopt diversified lifestyles which were normally not adopted in the old traditional systems. Such practices include habitation of tsetse fly infested areas, change of land tenure, adoption of sedentary lifestyle, use of cash as a basis for most transactions, use of livestock manure and chemicals to improve crop and livestock production, adoption of commercial horticultural farming, change of dietary habits, engagement in various small—scale business activities, and emphasis on child education and training. Albeit the differences in ecological potential of the study areas, management practices and other behaviours were similar in both study areas (eco—zones). In a few cases however, differences in the management levels existed between the two communities. For instance, the proportions of livestock owned in terms of cattle, sheep, goats, chickens, rabbits and ducks and varied (P<0.00l) between eco—zones. Kasikeu maintained higher proportions than Mtito-Andei of sheep (11.2% versus 7.2%) and rabbits (2.8% versus 0.2%) but a smaller proportion of goats (22.4% versus 30.4%). The number of donkeys encountered in the two areas were too few to warrant inclusion in the analysis. The proportions of livestock prices offered by buyers and accepted by the agro—pastoralists at the local market places, for cattle, sheep and goats varied (P<0.001) between eGo— zones. Kasikeu earned higher proportions than Mtito—Andei of the income from cattle sales (91.5% versus 79.2%) whereas Mtito-Andei earned higher proportions than Kasikeu of the income from sales of sheep (4.8% versus 1.0%) and goats (16.0% versus 7.5%). Proportions of the on—farm and off—farm watering places also varied (P<0.004) between eco—zones. Kasikeu respondents more commonly than Mtito—Andei respondents (77.4% versus 40.7%), watered their livestock on water sources located within their farms. The proportions of the total off-farm income attributed to salary/wage earning as being either greater or less than 50%, varied ( P<0.032) between eco—zones. Mtito—Andei recorded a higher proportion than Kasikeu (87.5% versus 64.5%), of the respondents receiving 50% or less of their total farm income from salary/wage earning. Although the proportions of incomes from the sources of the total off—farm income did not vary between eco—zones, those proportions varied (P<0.046) between sources in the entire study area. Greater proportions of the respondents indicated that over 50% of off—farm income came from small scale local businesses (36.5% versus 23.8% for salary/wage and 17.5% for kin remittance). The proportions of the total farm income attributed to crop and livestock production did not vary between eco—zones but varied (P<0.001) between production types in the entire study area. Crop production contributed more than a half (76.2% versus 22.2%). Similarly, proportions of the respondents ranking items of total family income expenditure in terms of purchase of foodstuff, school expenses, household expenses, purchase of clothes and miscellaneous expenses did not vary between eco— zones but varied (P<0.001) between items of expenditure in the entire study area. School expenses, had the greatest proportion (74.1%) of the respondents ranking it as number one user of total family income than any other item, Clothing and household expenses had the greatest proportions of the respondents (65. 2%) and (43 . 5%), respectively ranking them as number two users of the total family income. The following global recommendations are envisioned as necessary. 1. a. Promotion of integrated research efforts to develop technologies appropriate for small holdings in rangelands should be one of the aims within the framework of policy planners and, research and social scientists. For the agricultural research, the following areas may be given emphasis: soil and water conservation; dryland farming including small-scale irrigation methods; establishment of dryland fodder and shrub species; and improved dual purpose livestock including poultry and beekeeping, to mention a few. b. Promotion of small—scale business training and management activities the benefit of the interested farmers. c. Promotion of child basic education through government and non—governmental subsidies. d. Posting by government of adequate home—economic extension workers to teach family life education since a considerable number of respondents of the study were women. Area—specific recommendations are envisioned to include the following. 2. a. Kasikeu farmers, should promote growth of fodder crops to increase milk from cows whereas Mtito—Andei farmers should grow fodder shrubs for their goats. b. Due to small land sizes, farmers in Kasi]ceu and in Mtito— Andei should consider keeping fewer but productive dual purpose cattle and goats, respectively. c. Whereas farmers in Mtito-Andei would posssibly need to form committees to protect communal water from misuse, Kasikeu farmers would need to take care of their own individual water sources. e. Promotion of the small—scale rural industries especially in Mtito-Andei ‘area which is far away from the city for the creation of jobs. 3. Further research would be necessary to asses other agro— pastoral communities not only in Makueni district but also in other sub-divided range districts of Kenya. The design of such research should have replicated eco—zone units to allow for a wider and reliable generalization of the findings. This will be possible only if research budget, personnel and logistics are well taken care of. 4. Adoption of the above recommendations should not be expected to offer lasting solutions to the problems of farmers.

Tese de doutoramento em Biologia (Ecologia) apresentada à Fac. de Ciências e Tecnoloiga da Univ. de Coimbra<br>As a consequence of the industrial and socio-demographic changes of the last decades, the characteristic land use practices of extensive agro-pastoral systems in the region of Alentejo, Southern Portugal are being gradually abandoned and the consequences are still little understood. Land use changes are important drivers of environmental degradation, modification and fragmentation of habitats with the subsequent alterations of global carbon and hydrological cycles, global and regional climate, and decline in biodiversity. This work aims to contribute to a better understanding of the effects of abandonment in ecosystems with a long history of human management, as is the case of the agro-pastoral systems of Southern Portugal. Three land use categories were selected to represent a decrease in land use intensity (‘grazing’, ‘intermediate succession’ and advanced succession’). Following abandonment, secondary succession is expected to occur with consequent changes in soil characteristics and vegetation composition and structure. Because plant species differ in their functional traits and in their effects on ecosystem processes, an effect of land use change at this level may also be expected. Plant traits relate to universal plant functions of growth (e.g. light and nutrient acquisition, water use efficiency) and persistence (e.g. recruitment, dispersal, defence against herbivores and other disturbances). They provide a widely applicable framework for interpreting community shifts along environmental gradients, including secondary succession. The main objectives were to (1) identify changes in vegetation composition and structure in response to decreasing land use intensity; (2) Identify functional groups and changes in species traits in response to decreasing land use intensity; (3) Identify the effect of decreasing land use intensity in key ecosystem processes such as decomposition and above-ground net primary productivity (ANPP). Overall, the results from the present study showed that abandonment resulted in changes in species composition and richness, in plant functional traits and functional groups and in ecosystem processes (biomass, ANPP and decomposition). Secondary succession resulting from abandonment of grazing showed stronger changes in vegetation composition and structure than in soil characteristics. Among the soil chemical properties tested, only phosphorus, carbon and organic matter were affected by land use change. Phosphorus decreased with abandonment while organic matter and carbon showed an increase. Species richness decreased sharply after land abandonment, and this was associated with a strong turnover in species composition from grazed to abandoned sites as the vegetation changed from annual herbaceous to shrub-dominated communities. One single species (Cistus ladanifer) accounted for more than 50% of relative cover in the areas abandoned for a longer time, suggesting that this species might have an important role in possible changes in ecosystems processes. The species that colonized the different land use categories differed in plant functional traits. Therophyte life form, short canopy height, high specific leaf area (SLA), low leaf dry matter content (LDMC) and small seeds with dispersal structures were dominant at grazed plots. Within abandoned plots, chamaephytes dominanted at ‘intermediate succession’ plots and decrease in favour of nanophanerophytes in ‘advanced succession’ plots. Canopy height, LDMC and seed mass increase with abandonment time while SLA decreased. Functional response groups were found by combining life form and SLA and these were found to be sufficient to describe vegetation change. Therophytes with medium SLA were the dominant functional group in grazed areas, while nanophanerophytes with medium or low SLA were associated with later phases of abandonment. At intermediate stages of succession the dominant group was chamaephytes with medium SLA but functional diversity was highest as all the groups, except hemicriptophytes with medium SLA, were represented. Our study showed an increase in total above-ground biomass with abandonment indicating a positive effect of the shift to woody vegetation on total above-ground biomass. ANPP significantly increased in plots abandoned for longer time. This increase was strongly related with the increase in the cover of Cistus ladanifer. This is a pioneer species that colonises degraded areas and forms one of the first stages of succession of woody communities. Under favourable conditions, C. ladanifer can grow fast and attain large amounts of biomass in a short time and quickly spreads over recently disturbed areas. Regarding decomposition, shrub litter was found to be higher than herbaceous litter in nutrient content, especially nitrogen, which seemed to favour higher initial decomposition rates but lower decomposition rate in the longer term. Overall, decomposition was slower in abandoned than in grazed plots and this was positively correlated with the content of cellulose and hemicellulose of initial litter. Lower rates of decomposition were also found to be related to the increase in LDMC, a trait strongly linked to physical attributes of the leaves.<br>Em consequência da rápida evolução da indústria e alterações sócio-demográficas das ultimas décadas, assistiu-se a um abandono gradual das praticas de agricultura e pastorícia extensivas típicas dos sistemas agro-silvo-pastoris do Alentejo. Os efeitos desse abandono nas características da vegetação e no funcionamento do ecossistema são ainda pouco conhecidos. As alterações no uso do solo conduzem a perda, modificação e fragmentação de habitats e a consequentes alterações dos ciclos globais da agua e do carbono, do clima regional e global, bem como a uma diminuição da biodiversidade. Este trabalho pretende contribuir para um melhor conhecimento dos efeitos do abandono de praticas de gestão extensivas em áreas em que estas são praticadas há séculos, como e o caso dos sistemas agro-pastoris do sul de Portugal. Para tal, foram seleccionadas três áreas representativas de diferentes intensidades de uso do solo (‘pastoreio’, ’sucessão intermédia’ e ‘sucessão avançada’). O abandono das praticas agro-pastoris da inicio a um processo de sucessão secundaria, o qual, e geralmente, acompanhado por alterações físico-químicas do solo bem como por alterações da composição e estrutura da vegetação. As espécies vegetais diferem quer nos atributos funcionais que as caracterizam quer no modo como influenciam o funcionamento dos ecossistemas. Os atributos funcionais estao relacionados com aspectos como o crescimento (aquisição de luz e nutrientes, eficiência no uso da agua) e a sobrevivência (dispersão, regeneração, protecção contra herbívoros e outras perturbações). Estes permitem interpretar variações nas comunidades vegetais ao longo de gradientes ambientais, nos quais se pode incluir a sucessão secundaria. Em resposta ao abandono, foram objectivos deste trabalho identificar: (1) alterações na composição e estrutura da vegetação; (2) grupos funcionais e variações nos atributos funcionais; (3) efeitos na biomassa e produtividade primaria da parte aérea, bem como na taxa de decomposição da folhada. Os resultados deste estudo demonstraram que o abandono tem como consequências a alteração da composição e número de espécies, dos atributos funcionais e grupos funcionais, bem como das propriedades do ecossistema estudadas (biomassa e produtividade primaria da parte aérea, e decomposição da folhada). Os efeitos do abandono de praticas agro-pastoris extensivas nas áreas de estudo foram mais visíveis na composição e estrutura da vegetação do que nas características do solo. De entre os parâmetros do solo determinados, apenas se registaram alterações no conteúdo em fósforo, carbono e matéria orgânica. Observou-se uma diminuição de fósforo e um aumento de carbono e matéria orgânica em função do tempo de abandono. A riqueza específica diminuiu significativamente após o abandono e foi acompanhada por uma considerável alteração da composição florística, sendo que comunidades maioritariamente compostas por herbáceas anuais foram substituídas por comunidades arbustivas. Nas áreas de ‘sucessão avançada’ há dominância de uma espécie, Cistus ladanifer, responsável por mais de 50% da cobertura relativa, o que sugere que esta espécie pode ter um efeito importante no funcionamento destes ecossistemas. As espécies presentes nas diferentes categorias de uso do solo apresentaram diferenças nos atributos funcionais. Atributos associados as áreas com pastoreio incluem, forma de vida terofita, plantas de pequeno porte, área especifica da folha (SLA) elevada, teor de matéria seca da folha (LDMC) baixo, sementes pequenas com mecanismos de dispersão. Relativamente as areas abandonadas, os camefitos dominam nas areas de ‘sucessão intermédia’, diminuindo em favor dos nanofanerofitos nas áreas de ‘sucessão avançada’. Os atributos altura da copa, LDMC e massa da semente aumentaram com o tempo de abandono enquanto a SLA diminuiu. Através da combinação de dois atributos, forma de vida e SLA, foi possível identificar grupos funcionais de resposta. Terofitos com SLA media foram o grupo funcional dominante nas áreas de pastoreio, enquanto os nanofanerofitos com SLA media ou elevada foram o grupo dominante nas áreas de ‘sucessão avançada’. Em fases intermédias da sucessão o grupo dominante foram os camefitos com SLA média, mas a diversidade de grupos funcionais foi mais elevada do que nas restantes categorias pois todos os grupos, com excepção de hemicriptofitos com SLA média, estavam representados. O estudo apresentado mostrou um aumento da biomassa da parte aérea total com o aumento do tempo de abandono indicando um efeito positivo da substituição de espécies herbáceas por espécies arbustivas na biomassa aérea total. A produtividade primária líquida da parte aérea foi significativamente mais alta nas áreas abandonadas há mais tempo. Este aumento deveu-se em grande parte ao aumento da cobertura de Cistus ladanifer. Esta espécie e pioneira na colonização de solos degradados e forma um dos primeiros estados da sucessão de comunidades arbustivas. Em condições favoráveis esta espécie pode acumular grandes quantidades de biomassa em pouco tempo e rapidamente colonizar áreas recentemente perturbadas. A análise da qualidade inicial da folhada mostrou valores mais elevados de azoto na folhada das áreas abandonadas, o que parece ter contribuído para a decomposição rápida destes tipos de folhada em fases iniciais e mais lenta em fases mais tardias. Em termos gerais, a decomposição da folhada foi mais lenta nas áreas abandonadas do que nas áreas com pastoreio. Os resultados mostraram uma correlação positiva entre a taxa de decomposição e o conteúdo inicial de celulose e hemicelulose da folhada. Adicionalmente, registou-se uma correlação negativa entre a taxa de decomposição e a LDMC, um atributo relacionado com a composição estrutural das folhas.