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2 resultados encontrados para: AUTOR: Baraloto, Christopher
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1.
Artículo
*En hemeroteca, SIBE-San Cristóbal
Differential seedling growth response to soil resource availability among nine neotropical tree species
Baraloto, Christopher ; Bonal, Damien (coaut.) ; Goldberg, Deborah E. (coaut.) ;
Contenido en: Journal Tropical Ecology Vol. 22, no. 5 (September 2006), p. 487-497 ISSN: 0266-4674
Bibliotecas: San Cristóbal
Cerrar
SIBE San Cristóbal
B9384 (Disponible)
Disponibles para prestamo: 1
Nota: En hemeroteca, SIBE-San Cristóbal
Resumen en: Español |
Resumen en español

Although the potential contribution to tropical tree species coexistence of niche differentiation along light gradients has received much attention, the degree to which species perform differentially along soil resource gradients remains unclear. To examine differential growth response to soil resources, we grew seedlings of nine tropical tree species at 6.0% of full sun for 12 mo in a factorial design of two soil types (clay and white sand), two phosphate fertilization treatments (control and addition of 100 mg P kg[minus sign]1) and two watering treatments (field capacity and water limitation to one-third field capacity). Species differed markedly in biomass growth rate, but this hierarchy was almost completely conserved across all eight treatments. All species grew more slowly in sand than clay soils, and no species grew faster with phosphate additions. Only Eperua grandiflora and E. falcata showed significant growth increases in the absence of water limitation. Faster-growing species were characterized by high specific leaf area, high leaf allocation and high net assimilation rate but not lower root allocation.

Slower-growing species exhibited greater plasticity in net assimilation rate, suggesting that tolerance of edaphic stress in these species is related more to stomatal control than to whole-plant carbon allocation. Although relative growth rate for biomass was correlated with both its physiological and morphological components, interspecific differences were best explained by differences in net assimilation rate across six of the eight treatments. A suite of traits including high assimilation and high specific leaf area maintains rapid growth rate of faster-growing species across a wide gradient of soil resources, but the lack of plasticity they exhibit may compromise their survival in the poorest soil environments.


2.
- Artículo con arbitraje
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Resumen en: Español | Inglés |
Resumen en español

Se ofrece una evaluación del campo de la biología conservacionista con el propósito de dilucidar por qué muchos esfuerzos conservacionistas han tenido un éxito muy limitado; se proponen enfoques alternativos que pueden ser de utilidad para hecer más efectiva a la disciplina. La discusión se centra en la impresión de que la biología conservacionista falla, generalmente, en poder reconocer que las inequidades sociales son muchas veces causales de degradación ecológica; esta falla se traduce muchas veces en investigaciones y programas conservacionistas ineficaces. Se hace una descripción sobre cómo el conocimiento en profundidad y la discusión explícita del trasfondo social de los problemas de conservación ambiental pueden mejorar la efectividad de las investigaciones científicas, sin comprometer el rigor del método científico; también se delinean tres técnicas concretas que pueden ayudar a alcanzar esta meta: observación participativa, construcción de coaliciones y abogacía.

Resumen en inglés

We offer an evaluation of the field of conservation biology with the intent of elucidating why many conservation efforts meet with limited success, and we propose alternative approaches that may be useful in making the discipline more effective. Our discussion centers on our sense that conservation biology generally fails to formally acknowledge that social inequalities among people are often (although not always) basal causes of environmental degradation. This failure often results in ineffective research and conservation programs. We describe how an in-depth understanding and explicit discussion of the social background of conservation problems can help improve the effectiveness of scientific inquiry, without compromising the rigor of scientific methods, and we outline three concrete techniques that may help accomplish this goal: participatory research, coalition-building, and advocacy.