Effects of Forest Fragmentation on Recruitment Patterns in Amazonian Tree Communities

Laurance, William F.; Ferreira, Leandro Valle; Merona, Judy M. Rankin-de; Laurance, Susan G.; Hutchings, Roger William; Lovejoy, Thomas Ε.

doi:10.1111/j.1523-1739.1998.97175.x

Cited by 133 publications

(71 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Then, this result is concordant to other studies documenting negative effects of fragmentation on native biodiversity (e.g. Saunders et al 1991, Soulé et al 1992, Gilliam et al 1995, Laurance et al 1998, Tabarelli et al 1999, Hersperger & Forman 2003, Lindenmayer & Fischer 2006, Echeverría et al 2007, Schmitt et al 2010. As with exotic species, environmental changes produced by fragmentation (Chen et al 1995, Murcia et al 1995 may be detrimental for some forest-specialist native species.…”

Section: Discussionsupporting

confidence: 80%

“…Saunders et al 1991, Soulé et al 1992, Gilliam et al 1995, Laurance et al 1998, Tabarelli et al 1999, Hersperger & Forman 2003, Lindenmayer & Fischer 2006, Echeverría et al 2007, Schmitt et al 2010, as well as increases in exotic species diversity and abundance (Brothers & Spingarn 1992, Hobbs & Huennecke 1992, Wilson et al 1992, D'Antonio 1993, Mooney & Hobbs 2000, Hobbs 2001, Rouget et al 2002, Pauchard & Alaback 2004, Sax et al 2005. These fragmentation effects may be related to micro-environmental changes in the new edges, such as increase of light, higher temperatures and the potential release of other resources (Saunders et al 1991, Brothers & Spingarn 1992, Chen et al 1995, Hobbs 2001).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Relationship between fragmentation, degradation and native and exotic species richness in an Andean temperate forest of Chile

et al. 2011

View full text Add to dashboard Cite

Human impact such as forest fragmentation and degradation may have strong effects on native and exotic plant communities. In addition, these human-caused disturbances occur mostly in lowlands producing greater fragmentation and degradation there than in higher elevations. Plant invasion should be greater in more fragmented and degraded forests and hence lowlands should be more invaded than higher elevations. In turn, native species richness should be negatively related to fragmentation and degradation and hence greater in higher elevations within a forest type or elevation belt. We assessed these hypotheses in an Andean temperate forest of southern Chile, Araucanía Region. We recorded the vascular plant composition in twelve fragments of different size, perimeter/area, elevation level and evidence of human degradation (logging, fire, cattle faeces). Based on these variables we performed a fragmentation and a degradation index. Pearson correlations were used to analyze the relationship between all these variables. We found that fragmentation and degradation were positively correlated, and each of them decreased with altitude. Furthermore, fragmentation and degradation affected native and exotic species richness in different ways. Invasion was enhanced by both fragmentation and degradation, and as consequence of the altitudinal patterns of these human-caused disturbances, invasion seems to occur mainly in lowlands. In turn, native species richness decreased with fragmentation, and it was not related to degradation nor altitude. KEYWORDS:Fragmentation, forest degradation, elevation gradient, invasion, plant diversity. RESUMENImpactos humanos tales como la fragmentación y degradación de bosques pueden tener fuertes efectos en las comunidades de especies vegetales nativas y exóticas. Además, perturbaciones antrópicas ocurren principalmente en menores altitudes produciendo mayores grados de fragmentación y degradación que en mayores altitudes. La invasión de plantas exóticas debería ser mayor en bosques más fragmentados o degradados y, por lo tanto, en menores altitudes dentro de un tipo de bosque o piso altitudinal. En cambio, la riqueza de especies nativas debería ser negativamente afectada por la fragmentación y degradación, encontrándose mayor riqueza en mayores altitudes dentro de un tipo de bosque determinado. En este trabajo evaluamos estas hipótesis en un bosque templado andino de la Región de la Araucanía, Chile. Registramos la composición de plantas vasculares en doce fragmentos de diferente tamaño, razón perímetro/área, altitud y degradación antrópica (cortas, incendios, fecas de ganado). En base a estas variables construimos un índice de fragmentación y uno de degradación para estos fragmentos. Se analizaron las relaciones entre estas variables a través de correlaciones de Pearson. Nuestros resultados sugieren que la fragmentación y degradación están positivamente relacionadas y que ambos tipos de perturbación ocurren en altitudes más bajas del tipo de bosque estudiado. Además, la fragmentación y d...

show abstract

Section: Discussionsupporting

confidence: 80%

Section: Introductionmentioning

confidence: 99%

Relationship between fragmentation, degradation and native and exotic species richness in an Andean temperate forest of Chile

et al. 2011

View full text Add to dashboard Cite

show abstract

“…Forest fragmentation modifies the structure, diversity, dynamics, and species composition of arboreal communities through habitat reduction and edge effects on tree mortality and recruitment rates (2,3), liana proliferation (4), and invasive species (5). In addition, fragmentation reduces area of habitat necessary for many vertebrates (herbivores, seed predators, or seed dispersers) to maintain viable populations (6,7).…”

mentioning

confidence: 99%

Anthropogenic disturbances jeopardize biodiversity conservation within tropical rainforest reserves

Martı́nez-Ramos

Ortiz-Rodríguez

Piñero

et al. 2016

Proc. Natl. Acad. Sci. U.S.A.

117

102

View full text Add to dashboard Cite

Anthropogenic disturbances affecting tropical forest reserves have been documented, but their ecological long-term cumulative effects are poorly understood. Habitat fragmentation and defaunation are two major anthropogenic threats to the integrity of tropical reserves. Based on a long-term (four decades) study, we document how these disturbances synergistically disrupt ecological processes and imperil biodiversity conservation and ecosystem functioning at Los Tuxtlas, the northernmost tropical rainforest reserve in the Americas. Deforestation around this reserve has reduced the reserve to a mediumsized fragment (640 ha), leading to an increased frequency of canopy-gap formation. In addition, hunting and habitat loss have caused the decline or local extinction of medium and large herbivores. Combining empirical, experimental, and modeling approaches, we support the hypothesis that such disturbances produced a demographic explosion of the long-lived (≈120 y old, maximum height of 7 m) understory palm Astrocaryum mexicanum, whose population has increased from 1,243-4,058 adult individuals per hectare in only 39 y (annual growth rate of ca. 3%). Faster gap formation increased understory light availability, enhancing seed production and the growth of immature palms, whereas release from mammalian herbivory and trampling increased survival of seedlings and juveniles. In turn, the palm's demographic explosion was followed by a reduction of tree species diversity, changing forest composition, altering the relative contribution of trees to forest biomass, and disrupting litterfall dynamics. We highlight how indirect anthropogenic disturbances (e.g., palm proliferation) on otherwise protected areas threaten tropical conservation, a phenomenon that is currently eroding the planet's richest repositories of biodiversity.H uman activities operate as dominant drivers of biodiversity change and disruption of ecosystem processes in tropical forest ecosystems (1). Forest fragmentation modifies the structure, diversity, dynamics, and species composition of arboreal communities through habitat reduction and edge effects on tree mortality and recruitment rates (2, 3), liana proliferation (4), and invasive species (5). In addition, fragmentation reduces area of habitat necessary for many vertebrates (herbivores, seed predators, or seed dispersers) to maintain viable populations (6, 7). Fragmentation also facilitates poaching of game animals (7,8), which, in turn, disrupts trophic interactions that are critical for the maintenance of species diversity (9, 10). More specifically, fragmentation reduces population sizes of some shadetolerant tree species while fostering the presence of generalist and pioneer plant species (5, 11). Additionally, defaunation is differential, leading to the disappearance or decline of medium and large herbivores (12), and favors the proliferation of large-seeded, shadetolerant tree species (13). All these changes reduce tree diversity in forest fragments (14,15). Studies documenting the effects of forest fr...

show abstract

“…The absence of edge effects in open tropical formations has also been reported by Queiroga and Rodrigues (2005) and Santos and Santos (2008), for areas of Caatinga and Cerrado, in Brazil. The opposite has been verified in dense forests, such as the Amazon (Laurance et al 1998). It is possible that the effect of the formation of an edge is inversely proportional to the natural openness of the canopy.…”

Section: Discophora Guianenses Manikara Rufula Pouteria Bangii Sorocementioning

confidence: 86%

The influence of land use on edge effect in an Atlantic forest fragment in north-east Brazil

et al. 2012

View full text Add to dashboard Cite

Influencia del uso del suelo sobre el efecto de borde en un fragmento de bosque atlántico en el noreste de Brasil SUMMARYAlthough the edge effect is a phenomenon much studied in tropical forests, the effects of edge creation in open ombrophilous forests of the Atlantic Forest of northeastern Brazil are little discussed. Plant communities with large canopy openness, including periods with partial loss of leaves may respond differently to the impacts of edge formation because species may be more light-tolerant. The matrix can have a direct influence on the edge effect. Most studies available examine the consequences of the interface between forest and agricultural areas or pasturelands. However, the effects of the creation of a water body have been little studied, despite being frequent in the last century.In this study, we analyze the edge effect in two faces of a fragment, the first edge in contact with sugarcane crop, and the second with a lake formed by a dam. To neutralize the effect of selective logging and avoid counting species established before the edge formation, we analyzed the composition and density of the juvenile layer (≤ 1m). The results pointed out that the construction of a dam (water body) has caused an edge effect in the forest fragment, which seems to be not relevant in the area adjacent to sugarcane cultivation.Key words: rain forest, fragmentation, edge effect, Atlantic forest, Brazil. RESUMENSi bien el efecto de borde es un fenómeno ampliamente estudiado en bosques tropicales, los efectos de la creación de bordes en bosques abiertos ombrófilos del bosque atlántico del noreste de Brasil han sido poco discutido. Comunidades vegetales con una gran apertura de copa, incluyendo periodos con pérdida parcial de hojas pueden responder de manera diferenciada a los impactos de la formación de bordes ya que las especies pueden ser más tolerantes a la luz. La matriz puede tener una influencia directa sobre el efecto de borde. La mayoría de los estudios disponibles examinan las consecuencias de la interface entre el bosque y las áreas agrícolas o praderas. Sin embargo, los efectos de la creación de un cuerpo de agua han sido poco estudiados a pesar de ser frecuentes en el último siglo. En este estudio se analiza el efecto de borde en dos lados de un fragmento, el primer borde en contacto con un cultivo de caña y el segundo con un lago formado por una represa. Para neutralizar el efecto de madereo selectivo y evitar el conteo de especies establecidas antes de la formación del borde, se analiza la composición y densidad de la capa juvenil (≤ 1m). Los resultados indican que la construcción de una represa (cuerpo de agua) ha causado un efecto de borde en el fragmento de bosque, que parece no ser relevante en el área adyacente al cultivo de caña.Palabras clave: bosque lluvioso, fragmentación, efecto de borde, bosque atlántico, Brasil.

show abstract

Effects of Forest Fragmentation on Recruitment Patterns in Amazonian Tree Communities

Cited by 133 publications

References 13 publications

Relationship between fragmentation, degradation and native and exotic species richness in an Andean temperate forest of Chile

Relationship between fragmentation, degradation and native and exotic species richness in an Andean temperate forest of Chile

Anthropogenic disturbances jeopardize biodiversity conservation within tropical rainforest reserves

The influence of land use on edge effect in an Atlantic forest fragment in north-east Brazil

Contact Info

Product

Resources

About