184 research outputs found
Cognition, culture and utility:Plant classification by Paraguayan immigrant farmers in Misiones, Argentina
Background: This study was conducted in three rural communities of small farmers of Paraguayan origin living in the province of Misiones, Argentina. These Criollos (Mestizos) hail chiefly from departments located in the east of Paraguay, where the climate and flora have similar characteristics as those in Misiones. These ecological features contribute to the continuation and maintenance of knowledge and practices related to the use of plants. Methods: Fieldwork was conducted between September 2014 and August 2015. Forty five informants from three rural localities situated along the Parana River participated in an ethno-classification task. For the classification event, photographs of 30 medicinal and edible plants were chosen, specifically those yielding the highest frequency of mention among the members of that community (based on data obtained in the first stage of research in 2014). Variation in local plant classifications was examined and compared using principal component analysis and cluster analysis. Results: We found that people classify plants according to application or use (primarily medicinal, to a lesser extent as edible). Morphology is rarely taken into account, even for very similar and closely-related species such as varieties of palms. In light of our findings, we highlight a dominant functionality model at work in the process of plant cognition and classification among farmers of Paraguayan origin. Salient cultural beliefs and practices associated with rural Paraguayan plant-based medicine are described. Additionally, the manner by which residents’ concepts of plants articulate with local folk epistemology is discussed. Conclusions: Culturally constructed use patterns ultimately override morphological variables in rural Paraguayans’ ethnobotanical classification.Antecedentes: Este trabajo se realizó con pequeños agricultores de origen paraguayo, que habitan en la provincia de Misiones, Argentina. Los criollos (mestizos) en su mayoría provienen de departamentos ubicados al oriente del Paraguay, donde el clima y la flora presentan características similares a la provincia de Misiones. Estas características ecológicas contribuyen a la continuación y el mantenimiento de los conocimientos y las prácticas relacionados al uso de las plantas. Métodos El trabajo de campo se realizó entre septiembre de 2014 y agosto de 2015. En la etnoclasificación participaron 45 informantes, provenientes de tres localidades rurales, situadas a lo largo del río Paraná, frontera entre los dos países. Para la clasificación se utilizaron imágenes fotográficas de 30 especies -comestibles y medicinales- preseleccionadas como las de mayor frecuencia de mención entre los habitantes de la región (a partir de los datos obtenidos en una primera etapa de investigación en el año 2014). Por medio del análisis de componentes principales y el análisis de agrupamiento (cluster) se contrastaron y compararon las variaciones en las etnoclasificaciones locales de plantas. Resultados Se encontró que los pobladores clasifican sus plantas según su aplicación y uso (mayormente asociadas a la categoría medicinal y en menor medida a la comestible). Mientras, la morfología rara vez se tiene en cuenta, incluso en aquellas especies muy similares y estrechamente relacionadas como las palmeras. A la luz de los hallazgos, se destaca un modelo de funcionalidad dominante en el proceso de cognición y de clasificación de las plantas entre los agricultores de origen paraguayo. Se describen las principales creencias y prácticas culturales asociadas a la medicina rural paraguaya. Adicionalmente, se discuten algunos de los conceptos de las plantas que mantienen los paraguayos y su articulación con la epistemología local. Conclusiones En la clasificación etnobotánica de los pobladores de origen paraguayo los patrones de uso construidos culturalmente tienen mayor peso que las variables morfológicas.Fil: Kujawska, Monika. University Of Lodz; ArgentinaFil: Jiménez Escobar, Néstor David. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Antropología de Córdoba. Universidad Nacional de Córdoba. Facultad de Filosofía y Humanidades. Instituto de Antropología de Córdoba; ArgentinaFil: Nolan, Justin M.. University Of Arkansas; Estados UnidosFil: Arias Mutis, Daniel. University of Groningen; Países Bajo
Consequences of various landscape-scale ecosystem management strategies and fire cycles on age-class structure and harvest in boreal forests
At the landscape scale, one of the key indicators of sustainable forest management is the age-class distribution of stands, since it provides a coarse synopsis of habitat potential, structural complexity, and stand volume, and it is directly modified by timber extraction and wildfire. To explore the consequences of several landscape-scale boreal forest management strategies on age-class structure in the Mauricie region of Quebec, we used spatially explicit simulation modelling. Our study investigated three different harvesting strategies (the one currently practiced and two different strategies to maintain late seral stands) and interactions between fire and harvesting on stand age-class distribution. We found that the legacy of initial forested age structure and its spatial configuration can pose short- (<50 years) to medium-term (150-300 years) challenges to balancing wood supply and ecological objectives. Also, ongoing disturbance by fire, even at relatively long cycles in relation to historic levels, can further constrain the achievement of both timber and biodiversity goals. For example, when fire was combined with management, harvest shortfalls occurred in all scenarios with a fire cycle of 100 years and most scenarios with a fire cycle of 150 years. Even a fire cycle of 500 years led to a reduction in older forest when its maintenance was not a primary constraint. Our results highlight the need to consider the broad-scale effects of natural disturbance when developing ecosystem management policies and the importance of prioritizing objectives when planning for multiple resource use
Estimating the opportunity costs of environmental conservation in the Feijão River watershed (São Carlos-SP, Brazil)
The effects of spatial legacies following shifting management practices and fire on boreal forest age structure
Forest age structure and its spatial arrangement are important elements of sustainable forestry because of their effects on biodiversity and timber availability. Forest management objectives that include specific forest age structure may not be easily attained due to constraints imposed by the legacies of historical management and natural disturbance. We used a spatially explicit stochastic model to explore the synergetic effects of forest management and fire on boreal forest age structure. Specifically, we examined (1) the duration of spatial legacies of different management practices in the boreal forest, (2) how multiple shifts in management practices affect legacy duration and the spatial trajectories of forest age structure, and (3) how fire influences legacy duration and pattern development in combination with harvesting. Results based on 30 replicates of 500 years for each scenario indicate that (1) spatial legacies persist over 200 years and the rate at which legacies are overcome depends on whether new management targets are in synchrony with existing spatial pattern; (2) age specific goals were met faster after multiple management shifts due to the similar spatial scale of the preceding management types; (3) because large fires can erase the spatial pattern created by smaller disturbances, scenarios with fire had shorter lags than scenarios without fire. These results suggest that forest management goals can be accelerated by applying management at a similar spatial scale as existing spatial patterns. Also, management planning should include careful consideration of historical management as well as current and likely future disturbances
Diversity of small land mammals in a subtropical Atlantic forest in the western region of the state of Santa Catarina, southern Brazil
Competitive Asymmetries in the Use of Supplementary Food by the Endangered Iberian Lynx (Lynx pardinus)
Background: As a conservation tool, supplementary feeding programs may be directed to specific individuals or sectors of the target population whose productivity or survival is thought to be limited by food scarcity. However, the use of supplemental food by different sex and age classes has received little attention. We studied individual variation in the access of the endangered Iberian lynx (Lynx pardinus) to supplementary food.
Methodology/Principal Findings: From 5349 pictures taken with automatic cameras placed in 25 feeding stations, we identified 28 individuals whose sex and age were known. All individuals known to live in areas subjected to supplementation regularly visited feeding stations. Food consumption was not proportional to expected variations in energy demand within sex and age classes. Food consumption by males was higher than by females, and increased with age, in agreement with a despotic distribution. Food consumption also increased with lynx body mass, and this pattern held for individuals sharing the same breeding territories. The access of inferior competitors increased with the number of feeding stations available within lynx territories.
Conclusions/Significance: All lynx exposed to food supplementation made a regular use of extra food but individuals predicted to be competitively dominant visited stations more frequently than subordinates of the same breeding territory. Our results suggest that insufficient provision of supplementary food could restrict the access of juveniles, or even adult females, to feeding stations. Limited consumption by these target individuals may compromise the efficiency of the supplementary feeding programme at the population level, in endangered species that, as the Iberian lynx, exhibit marked sexual dimorphism in body size.Peer reviewe
Soil oribatid mite in four typical vegetation communities of Misiones forest in the Iguazú area, Argentina
Butterflies (Lepidoptera: Papilionoidea and Hesperioidea) of the Parque Ecológico João Vasconcelos Sobrinho, Caruaru, Pernambuco, Brazil
Genetic Diversity and Population History of a Critically Endangered Primate, the Northern Muriqui (Brachyteles hypoxanthus)
Social, ecological, and historical processes affect the genetic structure of primate populations, and therefore have key implications for the conservation of endangered species. The northern muriqui (Brachyteles hypoxanthus) is a critically endangered New World monkey and a flagship species for the conservation of the Atlantic Forest hotspot. Yet, like other neotropical primates, little is known about its population history and the genetic structure of remnant populations. We analyzed the mitochondrial DNA control region of 152 northern muriquis, or 17.6% of the 864 northern muriquis from 8 of the 12 known extant populations and found no evidence of phylogeographic partitions or past population shrinkage/expansion. Bayesian and classic analyses show that this finding may be attributed to the joint contribution of female-biased dispersal, demographic stability, and a relatively large historic population size. Past population stability is consistent with a central Atlantic Forest Pleistocene refuge. In addition, the best scenario supported by an Approximate Bayesian Computation analysis, significant fixation indices (ΦST = 0.49, ΦCT = 0.24), and population-specific haplotypes, coupled with the extirpation of intermediate populations, are indicative of a recent geographic structuring of genetic diversity during the Holocene. Genetic diversity is higher in populations living in larger areas (>2,000 hectares), but it is remarkably low in the species overall (θ = 0.018). Three populations occurring in protected reserves and one fragmented population inhabiting private lands harbor 22 out of 23 haplotypes, most of which are population-exclusive, and therefore represent patchy repositories of the species' genetic diversity. We suggest that these populations be treated as discrete units for conservation management purposes
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