202 research outputs found
Ecological restoration success is higher for natural regeneration than for active restoration in tropical forests
Is active restoration the best approach to achieve ecological restoration success (the return to a reference condition, that is, old-growth forest) when compared to natural regeneration in tropical forests? Our meta-analysis of 133 studies demonstrated that natural regeneration surpasses active restoration in achieving tropical forest restoration success for all three biodiversity groups (plants, birds, and invertebrates) and five measures of vegetation structure (cover, density, litter, biomass, and height) tested. Restoration success for biodiversity and vegetation structure was 34 to 56% and 19 to 56% higher in natural regeneration than in active restoration systems, respectively, after controlling for key biotic and abiotic factors (forest cover, precipitation, time elapsed since restoration started, and past disturbance). Biodiversity responses were based primarily on ecological metrics of abundance and species richness (74%), both of which take far less time to achieve restoration success than similarity and composition. This finding challenges the widely held notion that natural forest regeneration has limited conservation value and that active restoration should be the default ecological restoration strategy. The proposition that active restoration achieves greater restoration success than natural regeneration may have arisen because previous comparisons lacked controls for biotic and abiotic factors; we also did not find any difference between active restoration and natural regeneration outcomes for vegetation structure when we did not control for these factors. Future policy priorities should align the identified patterns of biophysical and ecological conditions where each or both restoration approaches are more successful, cost-effective, and compatible with socioeconomic incentives for tropical forest restoration
La vida cotidiana de los esclavos en las estancias jesuíticas de Córdoba
Fil: Crouzeilles, Carlos Alberto. Universidad Nacional de Córdoba. Facultad de Filosofía y Humanidades. Centro de Investigaciones "María Saleme de Burnichon" (CIFFyH); Argentina.El objetivo de este trabajo es abordar la vida cotidiana de los esclavos de la Compañía en relación con la producción, con la evangelización, con las festividades propias del calendario litúrgico y con las restricciones a la hora de ocupar ciertos espacios habitacionales o de labor en la cabecera de las estancias jesuíticas.Fil: Crouzeilles, Carlos Alberto. Universidad Nacional de Córdoba. Facultad de Filosofía y Humanidades. Centro de Investigaciones "María Saleme de Burnichon" (CIFFyH); Argentina.Otras Historia y Arqueologí
Religiosos y sociedad colonial : los religiosos, su ingreso a la Gobernación del Tucumán y su incidencia política en el sistema de explotación económico sobre la sociedad indígena (1535-1615)
Fil: Crouzeilles, Carlos.. Universidad Nacional de Córdoba. Facultad de Filosofía y Humanidades. Centro de Investigaciones. Área de Historia; Argentina.Este libro es una versión corregida del Trabajo Final de Licenciatura en Historia del autor. Su objetivo general es examinar la posición y actuación de los religiosos durante el período temprano de la Gobernación del Tucumán, poniendo especial atención en las políticas de dominación y explotación sobre la población indígena. El período investigado se extiende desde la entrada de los primeros religiosos al Tucumán en 1535 hasta 1615, año en que se producen una serie de acontecimientos político-eclesiásticos relevantes que modifican la postura de la Compañía de Jesús frente a los abusos de los encomenderos sobre la población indígena. El espacio estudiado corresponde al antiguo Obispado del Tucumán que fue erigido canónicamente en 1570 por el Papa Pío V, aunque se tienen en cuenta sus vínculos con las jurisdicciones de las cuales era sufragáneo y con el gobierno territorial de las congregaciones religiosas que, abarcando al Tucumán, lo superaba en extensión. En los cuatro capítulos que lo integran se profundiza sobre el período inicial de asentamiento y organización de la Iglesia, la posición y reacción de los religiosos y encomenderos frente a las ordenanzas del gobernador Gonzalo de Abreu (1576) y del visitador Francisco de Alfaro (1612), en un contexto de denuncias sobre el maltrato que padecían los indios y las presiones de un sector de religiosos y de algunos particulares para que la Corona española mandara, a través de la Audiencia de Charcas, un visitador a la región sur del virreinato y legislara sobre el tratamiento de los indios en las gobernaciones del Tucumán y del Paraguay.Fil: Crouzeilles, Carlos.. Universidad Nacional de Córdoba. Facultad de Filosofía y Humanidades. Centro de Investigaciones. Área de Historia; Argentina
DESLOCAMENTO NA MATRIZ PARA ESPÉCIES DA MATA ATLÂNTICA E A DIFICULDADE DA CONSTRUÇÃO DE PERFIS ECOLÓGICOS
INTER-HABITAT MOVIMENT FOR ATLANTIC FOREST SPECIES AND THE DIFICULTY TO BUILD ECOPROFILES. Few studies have evaluated the animals' capacity of inter-patch movement, which contributed to the buildup over the years of approaches that use a target species to represent and protect the local biodiversity. Recently, the ‘ecoprofiles' approach, seeks to fill some gaps left by other approaches. The ecoprofiles taking into account three main characteristics (type of ecosystem, area requirements and capacity of inter-patch movement) of target species, which may serve as representatives of a range of species that do not possess such information and demanding ‘similar' ecological requirements. Here, we performed a scientometric study on the subject of inter-patch movement, focusing on Atlantic Forest species. We also evaluated the possible use of ecoprofiles approach for this biome. In a general view, Brazil contributed with 0.005% to the total of published articles worldwide on the subject, which permit to conclude that the Brazilian contribution on the subject is still recent and restricted. Focusing in the Atlantic Forest biome, we found 24 papers published until January 2010, 15 of which presented explicit results on inter-patch movement for Atlantic Forest species. Among these 15 papers, the most common objective was to evaluate the species' dispersal capacity (the capacity to cross the matrix from one remnant forest to another). The non-volant mammals were the most frequent group in the articles and the birds showed the highest number of species studied. Only birds and small mammals were studied, probably because they are easily found and captured in remnant forests. This fact resulted in low values of inter-patch movement found for Atlantic Forest species. Moreover, this contribution presents a strong regional bias, since the state of Rio de Janeiro contributed all information about the subject for non-volant mammals and São Paulo for birds. Considering all the studies analyzed, although several aspects of the issue have been addressed, it is clear that knowledge about the ability to shift in the matrix is still very restricted. This fact, coupled with the lack of information on area requirements of the species, makes it virtually impossible to apply the ecoprofiles approach for the Atlantic Forest, at least in the short term.Keywords: Functional connectivity; gap crossing; perceptual range; Landscape Ecology; scientometrics.DESPLAZAMIENTO DE ESPECIES DEL BOSQUE ATLANTICO ENTRE PARCHES DE UNA MATRIZ Y LA DIFICULTAD DE CONSTRUIR PERFILES ECOLOGICOS. Pocos estudios han evaluado la capacidad de desplazamiento de especies entre parches de una matriz, que hayan contribuido a mejorar las aproximaciones que usan una especie blanco para representar y proteger la biodiversidad local. Recientemente, la aproximación de los “perfiles ecológicos” busca llenar algunos vacios dejados por otras aproximaciones. Esta tiene en consideración tres características principales de las especies blanco (tipo de ecosistema, requerimientos de área y capacidad de desplazamiento en la matriz), que pueden ser representativas de una gama de especies para la que no se posea información y tengan “similares” requerimientos ecológicos. En este trabajo realizamos un estudio cienciométrico sobre el desplazamiento entre parches de una matriz, enfocado en especies del Bosque Atlántico y evaluamos el uso posible de la aproximación de perfiles publicado mundialmente para este bioma. La contribución de Brasil es reciente y reducida. Para el Bosque Atlántico, encontramos 24 artículos publicados hasta enero del 2010, de los cuales solo 15 presentaron resultados explícitos de desplazamientos en la matriz para este bioma. De estos 15, el objetivo más común fue evaluar la dispersión de especies (capacidad de atravesar una matriz pasando de un hábitat a otro). Los mamíferos no voladores fueron el grupo más frecuente en los trabajos y las aves constituyeron el mayor número de especies estudiadas. Probablemente, por la mayor facilidad de captura y mayor ocurrencia en los parches boscosos, solo las aves y pequeños mamíferos fueron estudiados, lo que dio como resultado bajos valores de desplazamiento en la matriz para especies del Bosque Atlántico. Además, esta contribución muestra un fuerte sesgo regional ya que el estado de Río de Janeiro contribuye con toda la información sobre la temática para los mamíferos no voladores y Sao Paulo para las aves. Teniendo en consideración todos los estudios analizados, si bien algunos aspectos sobre la temática han sido considerados, se hace evidente que el conocimiento sobre la capacidad de desplazamiento de especies entre parches de una matriz es muy restringido. Este hecho junto con la carencia de información sobre requerimientos de área de las especies, hace prácticamente imposible aplicar la aproximación de los “perfiles ecológicos” en el Bosque Atlántico, al menos en el corto plazo. Palabras clave: Conectividad funcional; gap crossing; rango perceptual; Ecología del Paisaje; cienciometría.Poucos estudos têm avaliado a capacidade de deslocamento das espécies na matriz, o que contribuiu para o acúmulo ao longo dos anos de abordagens que utilizavam uma espécie alvo para representar e proteger a biodiversidade local, sendo a de perfis ecológicos a mais recente. Nesse estudo, realizamos um estudo cienciométrico com enfoque na temática deslocamento na matriz para espécies que ocorrem na Mata Atlântica e avaliamos o possível uso da abordagem de perfis ecológicos para o bioma. Em uma visão geral, o Brasil contribui com menos de 0,005% do que é publicado mundialmente sobre a temática. Com relação à Mata Atlântica, ao todo 24 artigos foram selecionados até janeiro de 2010, sendo que apenas 15 apresentaram valores explícitos de deslocamento na matriz para espécies desse bioma. Os mamíferos não-voadores foram os mais estudados e o grupo das aves foi o que apresentou o maior número de espécies estudadas. Rio de Janeiro e São Paulo são os estados que contribuem com a maior parte do conhecimento sobre a temática. Dentre os 15 artigos que apresentaram resultados explícitos sobre deslocamento na matriz, o objetivo mais comum foi avaliar a dispersão de espécies entre fragmentos florestais. A abordagem de perfis ecológicos não pode ser utilizada para a Mata Atlântica, já que não há informação suficiente sobre a capacidade de dispersão das espécies e das exigências de habitat, que é outra variável contida na abordagem. Podemos concluir que a contribuição brasileira sobre a temática é ínfima e recente, acarretando em baixos valores de deslocamento encontrados para espécies da Mata Atlântica, já que apenas aves e mamíferos de pequeno porte foram estudados. Isso ocorre por serem facilmente capturados e encontrados em fragmentos florestais, além de sofrerem um forte viés regional, já que o estado do Rio de Janeiro contribui com toda a informação sobre a temática para os mamíferos não-voadores e São Paulo para o grupo das aves. Considerando todos os estudos, diversos aspectos sobre a temática foram enfocados, no entanto, o conhecimento sobre o assunto ainda é muito restrito, o que torna a abordagem de perfis ecológicos inadequada para a Mata Atlântica
The role of natural regeneration to ecosystem services provision and habitat availability: a case study in the Brazilian Atlantic Forest
Natural regeneration provides multiple benefits to nature and human societies, and can play a major role in global and national restoration targets. However, these benefits are context specific and impacted by both biophysical and socioeconomic heterogeneity across landscapes. Here we investigate the benefits of natural regeneration for climate change mitigation, sediment retention and biodiversity conservation in a spatially explicit way at very high resolution for a region within the global biodiversity hotspot of the Atlantic Forest. We classified current land-use cover in the region and simulated a natural regeneration scenario in abandoned pasturelands, areas where potential conflicts with agricultural production would be minimized and where some early stage regeneration is already occurring. We then modelled changes in biophysical functions for climate change mitigation and sediment retention, and performed an economic valuation of both ecosystem services. We also modelled how land-use changes affect habitat availability for species. We found that natural regeneration can provide significant ecological and social benefits. Economic values of climate change mitigation and sediment retention alone could completely compensate for the opportunity costs of agricultural production over 20 years. Habitat availability is improved for three species with different dispersal abilities, although by different magnitudes. Improving the understanding of how costs and benefits of natural regeneration are distributed can be useful to design incentive structures that bring farmers’ decision making more in line with societal benefits. This alignment is crucial for natural regeneration to fulfil its potential as a large-scale solution for pressing local and global environmental challenges
Trophic consequences of introduced species: comparative impacts of increased inter-specific versus intra-specific competitive interactions
1. Invasive species can cause substantial ecological impacts on native biodiversity. Whilst ecological theory attempts to explain the processes involved in the trophic integration of invaders into native food webs and their competitive impacts on resident species, results are equivocal. In addition, quantifying the relative strength of impacts from non-native species (inter-specific competition) versus the release of native conspecifics (intra-specific competition) is important but rarely completed. 2. Two model non-native fishes, the globally invasive Cyprinus carpio and Carassius auratus, and the model native fish Tinca tinca, were used in a pond experiment to test how increased intra- and inter-specific competition influenced trophic niches and somatic growth rates. This was complemented by samples collected from three natural fish communities where the model fishes were present. The isotopic niche, calculated using stable isotope data, represented the trophic niche. 3. The pond experiment used additive and substitutive treatments to quantify the trophic niche variation that resulted from intra- and inter-specific competitive interactions. Although the trophic niche sizes of the model species were not significantly altered by any competitive treatment, they all resulted in patterns of inter-specific niche divergence. Increased inter-specific competition caused the trophic niche of T. tinca to shift to a significantly higher trophic position, whereas intra-specific competition caused its position to shift towards elevated 13C. These patterns were independent of impacts on fish growth rates, which were only significantly altered when inter-specific competition was elevated. 4. In the natural fish communities, patterns of trophic niche partitioning between the model fishes was evident, with no niche sharing. Comparison of these results with those of the experiment revealed the most similar results between the two approaches were for the niche partitioning between sympatric T. tinca and C. carpio. 5. These results indicate that trophic niche divergence facilitates the integration of introduced species into food webs, but there are differences in how this manifests between introductions that increase inter- and intra-specific competition. In entirety, these results suggest that the initial ecological response to an introduction appears to be a trophic re-organisation of the food web that minimises the trophic interactions between competing species
Incorporating habitat availability into systematic planning for restoration: A species-specific approach for Atlantic Forest mammals
AimSpecies persistence often depends not only on habitat protection, but also on habitat restoration. The effectiveness of species conservation through habitat restoration can be enhanced by explicitly considering habitat availability', the combined effects of the total amount of habitat and its spatial configuration. We develop an approach for prioritizing land for restoration in a complex biome, considering habitat availability, land acquisition cost and biogeographical representation
Natural regeneration and biodiversity: a global meta-analysis and implications for spatial planning
Natural regeneration offers a cheaper alternative to active reforestation and has the potential to become the predominant way of restoring degraded tropical landscapes at large-scale. We conducted a meta-analysis for tropical regions and quantified the relationships between both ecological and socioeconomic factors and biodiversity responses in naturally regenerating areas. Biogeographic realms, past disturbance, and the human development index (HDI) were used as explanatory variables for biodiversity responses. In addition, we present a case study of large-scale natural regeneration in the Brazilian Atlantic Forest and identify areas where different forms of restoration would be most suitable. Using our dataset for tropical regions, we showed that natural regeneration was predominantly reported within: the Neotropical realm; areas that were intensively disturbed; and countries with medium HDI. We also found that biodiversity in regenerating forests was more similar to the values found in old growth forests in: countries with either low, high, or very high HDI; less biodiverse realms; and areas of less intensive past disturbance. Our case study from Brazil showed that the level of forest gain resulting from environmental legislation, in particular the Brazilian Forest Code, has been reduced, but remains substantial. Complementary market incentives and financial mechanisms to promote large-scale natural regeneration in human-modified agricultural landscapes are also needed. Our analysis provides insights into the factors that promote or limit the recovery of biodiversity in naturally regenerating areas, and aids to identify areas with higher potential for natural regeneration
Reconciling rural development and ecological restoration: Strategies and policy recommendations for the Brazilian Atlantic Forest
Increased demand for both agricultural production and forest restoration may lead to increased competition for land in the next decades. Sustainably increasing cattle ranching productivity is a potential solution to reconcile different land uses, while also improving biodiversity conservation and the provision of ecosystem services. If not strategically implemented in integration with complementary policies, sustainable intensification can however result in negative environmental, economic and social effects. We analyzed the potential for sustainable intensification as a solution for a conflict between agricultural expansion and forest restoration in the Paraitinga Watershed at the Brazilian Atlantic Forest, a global biodiversity hotspot. In addition, we provide policy recommendations for sustainable development in the region, based on interviews with producers and local actors. We found that the Paraitinga Watershed has the potential to increase its cattle-ranching productivity and, as a result, relinquish spared land for other uses. This was true even in the most conservative intensification scenario considered (50% of the maximum potential productivity reached), in which 76,702 ha of pastures can be spared for other uses (46% of total pasture area). We found that restoration, apiculture and rural tourism are promising activities to promote sustainable development in the region, thus potentially increasing food production and mitigating competition for land. Our study shows that results from socioeconomic interviews and biophysical modelling of potential productivity increases offer robust insights into practical solutions on how to pursue sustainable development in one of the world’s most threatened biodiversity hotspots
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