CIFOR-ICRAF s’attaque aux défis et aux opportunités locales tout en apportant des solutions aux problèmes mondiaux concernant les forêts, les paysages, les populations et la planète.

Nous fournissons des preuves et des solutions concrètes pour transformer l’utilisation des terres et la production alimentaire : conserver et restaurer les écosystèmes, répondre aux crises mondiales du climat, de la malnutrition, de la biodiversité et de la désertification. En bref, nous améliorons la vie des populations.

CIFOR-ICRAF publie chaque année plus de 750 publications sur l’agroforesterie, les forêts et le changement climatique, la restauration des paysages, les droits, la politique forestière et bien d’autres sujets encore, et ce dans plusieurs langues. .

CIFOR-ICRAF s’attaque aux défis et aux opportunités locales tout en apportant des solutions aux problèmes mondiaux concernant les forêts, les paysages, les populations et la planète.

Nous fournissons des preuves et des solutions concrètes pour transformer l’utilisation des terres et la production alimentaire : conserver et restaurer les écosystèmes, répondre aux crises mondiales du climat, de la malnutrition, de la biodiversité et de la désertification. En bref, nous améliorons la vie des populations.

CIFOR–ICRAF publishes over 750 publications every year on agroforestry, forests and climate change, landscape restoration, rights, forest policy and much more – in multiple languages.

CIFOR–ICRAF addresses local challenges and opportunities while providing solutions to global problems for forests, landscapes, people and the planet.

We deliver actionable evidence and solutions to transform how land is used and how food is produced: conserving and restoring ecosystems, responding to the global climate, malnutrition, biodiversity and desertification crises. In short, improving people’s lives.

A mark-recapture study of coexisting Zygopteran populations

Exporter la citation

An analysis is presented of the coexistence of 8 springs spp. in an area in Eastern Flanders, Belgium. By counting exuviae an by the mark recapture method, the behavior of different spp. in space and time was followed the data include estimates of the translocation within the area and estimates of population size and servival rate using the method of jolly and seber and new regression method. -Between spp, (of different genera), differences in spatial and temporal performance were noted which resulted in a reduction of interaction, whether or not truly competitive. However, between the coexisting sibling spp,. Coenogrion puella and C. pulchellum, no major differences in utilization of the environment could be found. There are indications that qq of C. puella we were driven out of their favored areas, but in spite of this they continued to oviposit at the peak density of C.pulchellum. This observation lead to reconsideration of the competitive exclusion principle.
    Année de publication

    1978

    Auteurs

    van Noordwijk, M.

    Langue

    English

    Mots clés

    agroforestry, education, population

    Géographique

    Belgium

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