5 research outputs found
Las memorias de la dictadura: los vuelos de la muerte en Villa Paranacito y los centros clandestinos de detención en Entre Ríos
El plan de exterminio desplegado durante la última dictadura cívico militar involucró más de 800 Centros Clandestinos de Detención, buena parte de los cuales estuvieron ubicados en las tramas urbanas entrerrianas. En Argentina han sido señalizados más de un centenar de lugares de represión en un proceso de trabajo conjunto entre la nación, las administraciones provinciales y municipales. Estas leyes reconocen la labor realizada por los organismos en la salvaguarda de las memorias del terrorismo de Estado y establecen la preservación, señalización y difusión de sitios de memoria del terrorismo de Estado.
En la provincia de Entre Ríos estos organismos han impulsado la colocación de placas y carteles, y la señalización de distintos espacios de memoria con resultados diversos (Pisarello y Balcar, 2019). No obstante, los imaginarios sociales del litoral habitualmente plantean que la materialidad del terrorismo de estado estuvo anclada en las grandes ciudades - como Buenos Aires y Córdoba-, mientras que en las provincias del llamado “interior” no habría pasado nada (Badano, 2018).Universidad Nacional de La Plat
Limits to reproduction and seed size-number tradeoffs that shape forest dominance and future recovery
The relationships that control seed production in trees are fundamental to understanding the evolution of forest species and their capacity to recover from increasing losses to drought, fire, and harvest. A synthesis of fecundity data from 714 species worldwide allowed us to examine hypotheses that are central to quantifying reproduction, a foundation for assessing fitness in forest trees. Four major findings emerged. First, seed production is not constrained by a strict trade-off between seed size and numbers. Instead, seed numbers vary over ten orders of magnitude, with species that invest in large seeds producing more seeds than expected from the 1:1 trade-off. Second, gymnosperms have lower seed production than angiosperms, potentially due to their extra investments in protective woody cones. Third, nutrient-demanding species, indicated by high foliar phosphorus concentrations, have low seed production. Finally, sensitivity of individual species to soil fertility varies widely, limiting the response of community seed production to fertility gradients. In combination, these findings can inform models of forest response that need to incorporate reproductive potential
Limits to reproduction and seed size-number trade-offs that shape forest dominance and future recovery
International audienceThe relationships that control seed production in trees are fundamental to understanding the evolution of forest species and their capacity to recover from increasing losses to drought, fire, and harvest. A synthesis of fecundity data from 714 species worldwide allowed us to examine hypotheses that are central to quantifying reproduction, a foundation for assessing fitness in forest trees. Four major findings emerged. First, seed production is not constrained by a strict trade-off between seed size and numbers. Instead, seed numbers vary over ten orders of magnitude, with species that invest in large seeds producing more seeds than expected from the 1:1 trade-off. Second, gymnosperms have lower seed production than angiosperms, potentially due to their extra investments in protective woody cones. Third, nutrient-demanding species, indicated by high foliar phosphorus concentrations, have low seed production. Finally, sensitivity of individual species to soil fertility varies widely, limiting the response of community seed production to fertility gradients. In combination, these findings can inform models of forest response that need to incorporate reproductive potential
Globally, tree fecundity exceeds productivity gradients
Lack of tree fecundity data across climatic gradients precludes the analysis of how seed supply contributes to global variation in forest regeneration and biotic interactions responsible for biodiversity. A global synthesis of raw seedproduction data shows a 250-fold increase in seed abundance from cold-dry to warm-wet climates, driven primarily by a 100-fold increase in seed production for a given tree size. The modest (threefold) increase in forest productivity across the same climate gradient cannot explain the magnitudes of these trends. The increase in seeds per tree can arise from adaptive evolution driven by intense species interactions or from the direct effects of a warm, moist climate on tree fecundity. Either way, the massive differences in seed supply ramify through food webs potentially explaining a disproportionate role for species interactions in the wet tropics