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31.
Rubber tappers promoted extractive reserves as a sustainable alternative to forest destruction in the Brazilian Amazon. However, the significance of rubber tapping itself has declined since the creation of extractive reserves, which raises questions about the contemporary cultural content of the rubber tapper identity. This paper therefore evaluates rubber tapper identity, using the case of the Chico Mendes Extractive Reserve (CMER) in Acre, Brazil. We first draw on household survey data from the CMER to construct a statistical model of who self-identifies as a rubber tapper. The model shows that socio-economic background, household assets, institutional context, and knowledge of the CMER’s management plan are relevant to understanding rubber tapper self-identification, but not resource management practices, including rubber tapping itself. We therefore pursue qualitative analysis of key informant interviews to better apprehend contemporary understandings of the “rubber tapper” identity, particularly in light of recent shifts in livelihoods from rubber tapping toward cattle ranching. The qualitative analysis shows that there are now several different foundations for self-identifying as a “rubber tapper,” and that there are disagreements concerning the acceptability of cattle ranching among “rubber tappers.” These findings bear implications for research on the relationship of livelihood-based identities with resource management practices and environmental change, as well as public policies that seek to reconcile regional development with forest conservation. 相似文献
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Luc Denys 《Journal of Paleolimnology》2006,35(4):763-787
Relationships between littoral surface-sediment diatom assemblages and ambient limnological conditions were examined in 186
lentic fresh waters throughout lower Belgium (Flanders). Most of these waters were small, unstratified, alkaline and rich
in nutrients. Using weighted-averaging techniques, robust and accurate transfer functions were developed for median pH-values
ranging from 3.4 to 9.3 and dissolved inorganic carbon concentrations from <1.6 to 63 mg l−1 (jackknifed r
2≈ 0.87, RMSEP <10% of the observed range), while a less precise model was obtained for sodium (2–571 mg l−1; jackknifed r
2 0.69, RMSEP 9.9% of the range). Restricting the data set to circumneutral and alkaline sites (pH≥6.5) revealed the importance
of additional variables, including calcium, silica, chemical oxygen demand and potential gross oxygen production (a proxy
for metabolic activity and phytoplankton abundance). Calibration models for these variables were strong enough to be useful
(jackknifed r
2 0.57–0.59, RMSEP 13.1–16.4% of the observed range), although estimations should not always be considered entirely independent.
Except for the predominant pH gradient, removal of all taxa with a distribution unrelated to the variable of interest improved
model performance. In general, such taxa were proportionally represented among taxa classified according to their principal
habitat. Application of the present models to diatom assemblages of shallow-water sediments obtained from historical samples
and, most importantly, herbarium-macrophyte specimens, will improve hindsight into regional freshwater conditions and add
to base-line setting of ecological quality standards in a highly impacted region.
Electronic supplementary material Electronic supplementary material is available for this article at
and accessible for authorised users. 相似文献
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Patrick Hesp Janete Abreu de Castilhos Graziela Miot da Silva Sergio Dillenburg Caroline Thais Martinho Débora Aguiar Michele Fornari Milene Fornari Glauco Antunes 《地球表面变化过程与地形》2007,32(4):561-573
This paper examines a seemingly anomalous situation in southern Brazil where the dunefields on Santa Catarina Island (e.g. Joaquina Beach) migrate to the NNW, almost completely the opposite direction (c. 160) to the dunefields immediately to the south (e.g. Pinheira Beach), and some much further to the north (e.g. Cabo Frio) which migrate to the SSW. A variety of mechanisms are examined to explain the differences in dunefield migration including grain size variations, topographic effects on local winds, shoreline orientation, and regional wind field changes. The mean grain sizes of the two beaches, Pinheira and Joaquina, are not sufficiently different to restrict aeolian sediment transport in either place, nor to account for a lack of transport from the NNE to the SSW in the case of Joaquina. Some topographic steering of the wind is likely but could not account for the long‐term average difference in migration trends of the island dunefields compared to the mainland dunefields. While the orientation of the shoreline to prevailing winds is an important control on beach and dune sediment transport, it is not the dominant controlling mechanism. An analysis of the regional wind patterns demonstrates that there is a major shift in the regional wind field near the island such that the dominant island winds blow from the SW/SSW while those further south blow from the NE. It is concluded that this is the predominant reason for the divergence in the direction of migration of the dunefields. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
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Felício Cassalho Samuel Beskow Carlos Rogrio de Mello Maíra Martim de Moura Leroi Floriano de Oliveira Marilton Sanchotene de Aguiar 《水文研究》2019,33(7):1101-1116
Due to the severity related to extreme flood events, recent efforts have focused on the development of reliable methods for design flood estimation. Historical streamflow series correspond to the most reliable information source for such estimation; however, they have temporal and spatial limitations that may be minimized by means of regional flood frequency analysis (RFFA). Several studies have emphasized that the identification of hydrologically homogeneous regions is the most important and challenging step in an RFFA. This study aims to identify state‐of‐the‐art clustering techniques (e.g., K ‐means, partition around medoids, fuzzy C‐means, K ‐harmonic means, and genetic K ‐means) with potential to form hydrologically homogeneous regions for flood regionalization in Southern Brazil. The applicability of some probability density function, such as generalized extreme value, generalized logistic, generalized normal, and Pearson type 3, was evaluated based on the regions formed. Among all the 15 possible combinations of the aforementioned clustering techniques and the Euclidian, Mahalanobis, and Manhattan distance measures, the five best were selected. Several watersheds' physiographic and climatological attributes were chosen to derive multiple regression equations for all the combinations. The accuracy of the equations was quantified with respect to adjusted coefficient of determination, root mean square error, and Nash–Sutcliffe coefficient, whereas, a cross‐validation procedure was applied to check their reliability. It was concluded that reliable results were obtained when using robust clustering techniques based on fuzzy logic (e.g., K ‐harmonic means), which have not been commonly used in RFFA. Furthermore, the probability density functions were capable of representing the regional annual maximum streamflows. Drainage area, main river length, and mean altitude of the watershed were the most recurrent attributes for modelling of mean annual maximum streamflow. Finally, an integration of all the five best combinations stands out as a robust, reliable, and simple tool for estimation of design floods. 相似文献
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Aguiar Eva Mourre Baptiste Juza Mélanie Reyes Emma Hernández-Lasheras Jaime Cutolo Eugenio Mason Evan Tintoré Joaquín 《Ocean Dynamics》2020,70(2):273-288
Ocean Dynamics - In numerical ocean modeling, dynamical downscaling is the approach consisting in generating high-resolution regional simulations exploiting the information from coarser resolution... 相似文献
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Robert Barouki Manolis Kogevinas Karine Audouze Kristine Belesova Ake Bergman Linda Birnbaum Sandra Boekhold Sebastien Denys Celine Desseille Elina Drakvik Howard Frumkin Jeanne Garric Delphine Destoumieux-Garzon Andrew Haines Anke Huss Genon Jensen Spyros Karakitsios Jana Klanova Iida-Maria Koskela Francine Laden Paolo Vineis 《Chemie der Erde / Geochemistry》2011
The outbreak of COVID-19 raised numerous questions on the interactions between the occurrence of new infections, the environment, climate and health. The European Union requested the H2020 HERA project which aims at setting priorities in research on environment, climate and health, to identify relevant research needs regarding Covid-19. The emergence and spread of SARS-CoV-2 appears to be related to urbanization, habitat destruction, live animal trade, intensive livestock farming and global travel. The contribution of climate and air pollution requires additional studies. Importantly, the severity of COVID-19 depends on the interactions between the viral infection, ageing and chronic diseases such as metabolic, respiratory and cardiovascular diseases and obesity which are themselves influenced by environmental stressors. The mechanisms of these interactions deserve additional scrutiny. Both the pandemic and the social response to the disease have elicited an array of behavioural and societal changes that may remain long after the pandemic and that may have long term health effects including on mental health. Recovery plans are currently being discussed or implemented and the environmental and health impacts of those plans are not clearly foreseen. Clearly, COVID-19 will have a long-lasting impact on the environmental health field and will open new research perspectives and policy needs. 相似文献
38.
Robert Barouki Manolis Kogevinas Karine Audouze Kristine Belesova Ake Bergman Linda Birnbaum Sandra Boekhold Sebastien Denys Celine Desseille Elina Drakvik Howard Frumkin Jeanne Garric Delphine Destoumieux-Garzon Andrew Haines Anke Huss Genon Jensen Spyros Karakitsios Jana Klanova Paolo Vineis 《Chemie der Erde / Geochemistry》2013
The outbreak of COVID-19 raised numerous questions on the interactions between the occurrence of new infections, the environment, climate and health. The European Union requested the H2020 HERA project which aims at setting priorities in research on environment, climate and health, to identify relevant research needs regarding Covid-19. The emergence and spread of SARS-CoV-2 appears to be related to urbanization, habitat destruction, live animal trade, intensive livestock farming and global travel. The contribution of climate and air pollution requires additional studies. Importantly, the severity of COVID-19 depends on the interactions between the viral infection, ageing and chronic diseases such as metabolic, respiratory and cardiovascular diseases and obesity which are themselves influenced by environmental stressors. The mechanisms of these interactions deserve additional scrutiny. Both the pandemic and the social response to the disease have elicited an array of behavioural and societal changes that may remain long after the pandemic and that may have long term health effects including on mental health. Recovery plans are currently being discussed or implemented and the environmental and health impacts of those plans are not clearly foreseen. Clearly, COVID-19 will have a long-lasting impact on the environmental health field and will open new research perspectives and policy needs. 相似文献
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