La spatialisation de la biodiversité : pour la gestion durable des territoires

Depuis le sommet de Rio de Janeiro en 1992, la diversité du vivant n’est plus l’apanage des biologistes : le concept de biodiversité envisage les relations du monde biologique avec les sociétés. La diversité se trouve en effet à présent au cœur des préoccupations de développement durable et de conservation. L’Amazonie, considérée comme une région de très grande diversité, attire depuis longtemps toutes les convoitises mais suscite désormais des inquiétudes : la nature inépuisable nous apparaît dès lors comme une biodiversité en péril. Mais, comment évaluer l’état et les transformations de la biodiversité de cette immense région ? Quels sont les effets des nombreuses politiques publiques de développement et de conservation qui s’y sont multipliées ces dernières décennies ? Cet ouvrage présente d’abord la complexité de quelques situations locales amazoniennes – des systèmes agricoles indigènes aux fronts pionniers associés à l’élevage extensif. L’imagerie satellitale permet ensuite de cartographier les dynamiques de la biodiversité végétale dans l’espace et le temps à partir d’une analyse des paysages et de l’estimation de leur complexité grâce à une démarche pluridisciplinaire (de la botanique à l’anthropologie). Les transformations des paysages et les variations concomitantes de la biodiversité sont par ailleurs mises en relation avec les politiques publiques et les actions privées. L’approche méthodologique, volontairement simple, a été élaborée avec l’ambition d’être applicable à d’autres espaces forestiers tropicaux

Complexidade das paisagenes do projeto de assentamento benefica, sudeste paraense, estado do Para

International audienc

Efeitos da escala e configuração da paisagem sobre comunidades vegetais em uma paisagem antropizada no nordeste da Amazônia

O presente estudo objetiva avaliar o efeito das métricas de uma paisagem antropizada em diferentes escalas sobre os diferentes estratos da vegetação. Foram realizadas RDA entre as variáveis da vegetação vs. métricas de paisagem. As métricas proporção de área não-florestada e densidade de fragmentos influenciaram os três estratos da vegetação em todas as escalas, refletindo o forte efeito da perda de hábitat e fragmentação. As métricas relacionadas à ambientes bem preservados tem efeito consistente na escala de 2000 m

Linking spatialized indicators of desertification risks with observed land use/land cover change : an operational monitoring system of desertification

The need of useful information for decision-makers to fight against desertification in Tunisian dry zones leads to conceive assessing and monitoring systems that can supply synthetic indicators. These latter should integrate socioeconomic and environmental dimensions with their spatial and temporal diversity at the local scale. This paper proposes an example of information system entitled SIELO (information system for operational desertification monitoring at the local scale). This system attempts to create the link between i) spatialized indicators of desertification risks, built in connection with the systematic complexity of desertification and ii) observed Land Use/ Land Cover (LU/LC) Change. The first type of data arises from pre-existing environmental model: LEIS model (Local Environmental Information System). The second type of data is extracted from satellite images acquired according to regular time steps. The proposed approach is based also on the spatializing of knowledge, via the "landscape" tool in particular. We illustrate the feasibility and the operational effectiveness of a developed software prototype (SIELO v1.0) with an initial application in a Tunisian dry zone. This system showed that it has the capacity to feed an operational monitoring of desertification according to the state of LU/LC directly observed or measured in several dates. Then, it can be useful for the decision-makers in their programs of fighting against desertification, but also to manage uncertainties in southeastern Tunisia, especially climate variability and climate change

Efeitos da escala e configuração da paisagem sobre comunidades vegetais em uma paisagem antropizada no nordeste da Amazônia

O presente estudo objetiva avaliar o efeito das métricas de uma paisagem antropizada em diferentes escalas sobre os diferentes estratos da vegetação. Foram realizadas RDA entre as variáveis da vegetação vs. métricas de paisagem. As métricas proporção de área não-florestada e densidade de fragmentos influenciaram os três estratos da vegetação em todas as escalas, refletindo o forte efeito da perda de hábitat e fragmentação. As métricas relacionadas à ambientes bem preservados tem efeito consistente na escala de 2000 m

Linking spatialized indicators of desertification risks with observed land use/land cover change : an operational monitoring system of desertification

The need of useful information for decision-makers to fight against desertification in Tunisian dry zones leads to conceive assessing and monitoring systems that can supply synthetic indicators. These latter should integrate socioeconomic and environmental dimensions with their spatial and temporal diversity at the local scale. This paper proposes an example of information system entitled SIELO (information system for operational desertification monitoring at the local scale). This system attempts to create the link between i) spatialized indicators of desertification risks, built in connection with the systematic complexity of desertification and ii) observed Land Use/ Land Cover (LU/LC) Change. The first type of data arises from pre-existing environmental model: LEIS model (Local Environmental Information System). The second type of data is extracted from satellite images acquired according to regular time steps. The proposed approach is based also on the spatializing of knowledge, via the "landscape" tool in particular. We illustrate the feasibility and the operational effectiveness of a developed software prototype (SIELO v1.0) with an initial application in a Tunisian dry zone. This system showed that it has the capacity to feed an operational monitoring of desertification according to the state of LU/LC directly observed or measured in several dates. Then, it can be useful for the decision-makers in their programs of fighting against desertification, but also to manage uncertainties in southeastern Tunisia, especially climate variability and climate change