5,654 research outputs found

    Historical record of Corallium rubrum and its changing carbon sequestration capacity: A meta-analysis from the North Western Mediterranean

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    Background There is a scarcity of long time-span and geographically wide research on the health status of Corallium rubrum, including limited research on its historical ecology and carbon sequestration capacity. Objectives To reconstruct the temporal trends of the most reported C. rubrum population parameters in the Northwestern Mediterranean Sea and to determine the changes in total carbon sequestration by this species. Data sources Quantitative and qualitative, academic and grey documents were collected from scientific web browsers, scientific libraries, and requests to scientists. Study eligibility criteria Documents with original information of basal diameter, height and/or weight per colony, with a depth limit of 60 m in the Catalan and Ligurian Seas were analyzed. Synthesis methods We calculated yearly average values of C. rubrum biometric parameters, as well as estimated total weight, carbon flux, and carbon fixation in the structures of C. rubrum's colonies. Results In both study areas, the values of the selected morphometric parameters for C. rubrum decreased until the 1990s, then increased from the 2000s, with average values surpassing the levels of the 1960s (Ligurian Sea) or reaching levels slightly lower than those of the 1980s (Catalan Sea). The difference in carbon sequestered between the oldest (1960s: Ligurian Sea; 1970s: Catalan Sea) and the lowest (1990s) biomass value of colonies is nearly double. Limitations Quantitative data previous to the 1990s are very limited. Information on recent recovery trends in C. rubrum parameters is concentrated in a few areas and biased towards colonies in marine protected areas, with scarce quantitative information from colonies in other areas. Conclusions The halt in the C. rubrum decreasing trend coincided with the exhaustion of tree-like colonies and the first recovery response due to effective protection measures in some areas. Nevertheless, C. rubrum climate change mitigation capacity through carbon sequestration can be drastically reduced from its potential in only a few decades

    Local and tourist perceptions of coastal marine habitats in Cap de Creus (NE Spain)

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    Direct human pressure on Marine Protected Areas (MPAs) adds to climate change impacts on marine habitats, especially in coastal biodiversity hot spots. Understanding MPA user perception towards the Coastal marine Habitats (CMHs) could improve awareness of the challenges that such areas have to face, eventually providing insights for the design of conservation and tourism management plans. We studied perception of ecosystem services, impacts and threats of CMHs by locals and tourists (n = 624) of Cap de Creus MPA (NW Mediterranean Sea). Overall, we found that perceptions of tourists and locals are similar. Respondents perceived that CMHs provide valuable regulating services, and they assigned less value to cultural services. Locals valued the food provision ecosystem service of CMHs significantly more than tourists, probably because of the historical importance of fisheries for subsistence. Respondents ranked marine pollution of inland origin, climate change and people’s behaviour towards nature as the most impactful and threatening to CMHs, and invasive marine species as the least. Respondents also perceived that climate change impacts would increase soon, whilst the impact of people’s behaviour towards nature would decrease. Tourists perceived mass tourism as significantly more impactful and threatening to CMHs than locals did. Overall, our study shows that conservation of CMHs is highly valued, so more effort needs to be directed toward this goal

    The Role of Ethnobotanical Skills and Agricultural Labor in Forest Clearance: Evidence from the Bolivian Amazon

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    Research on the benefits of local ecological knowledge for conservation lacks empirical data on the pathways through which local knowledge might affect natural resources management. We test whether ethnobotanical skills, a proxy for local ecological knowledge, are associated to the clearance of forest through their interaction with agricultural labor. We collected information from men in a society of gatherers–horticulturalist, the Tsimane’ (Bolivia). Data included a baseline survey, a survey of ethnobotanical skills (n = 190 men), and two surveys on agricultural labor inputs (n = 466 plots). We find a direct effect of ethnobotanical skills in lowering the extent of forest cleared in fallow but not in old-growth forest. We also find that the interaction between ethnobotanical skills and labor invested in shifting cultivation has opposite effects depending on whether the clearing is done in old-growth or fallow forest. We explain the finding in the context of Tsimane’ increasing integration to the market econom

    Evaluating indices of traditional ecological knowledge: a methodological contribution

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    BACKGROUND: New quantitative methods to collect and analyze data have produced novel findings in ethnobiology. A common application of quantitative methods in ethnobiology is to assess the traditional ecological knowledge of individuals. Few studies have addressed reliability of indices of traditional ecological knowledge constructed with different quantitative methods. METHODS: We assessed the associations among eight indices of traditional ecological knowledge from data collected from 650 native Amazonians. We computed Spearman correlations, Chronbach's alpha, and principal components factor analysis for the eight indices. RESULTS: We found that indices derived from different raw data were weakly correlated (rho<0.5), whereas indices derived from the same raw data were highly correlated (rho>0.5; p < 0.001). We also found a relatively high internal consistency across data from the eight indices (Chronbach's alpha = 0.78). Last, results from a principal components factor analysis of the eight indices suggest that the eight indices were positively related, although the association was low when considering only the first factor. CONCLUSION: A possible explanation for the relatively low correlation between indices derived from different raw data, but relatively high internal consistency of the eight indices is that the methods capture different aspects of an individual's traditional ecological knowledge. To develop a reliable measure of traditional ecological knowledge, researchers should collect raw data using a variety of methods and then generate an aggregated measure that contains data from the various components of traditional ecological knowledge. Failure to do this will hinder cross-cultural comparisons

    Cash cropping, farm technologies, and deforestation: What are the connections?. Tsimane' Amazonian Panel Study Working Paper # 18, Dec-2005

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    Research suggests that cash-cropping is associated with deforestation. We use three-year data (2000-2002) from 493 households to estimate the association between cash-cropping rice and deforestation. Doubling the area sown with rice is associated with a 26-30% increase of the area of forest cleared next cropping season. We simulate the changes required to reach 1US$/person/day income with cash from rice. We find that within 10 years 1) deforestation would triple, 2) work requirements would exceed household’s labor availability, and 3) fallows duration would decrease two-fold. Avoiding growing deforestation due to cash-cropping by smallholders requires increasing productivity, diversification of income sources, or both

    Concepts and methods in studies measuring individual ethnobotanical knowledge

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    We review 34 quantitative studies that have measured individuallevel variations in ethnobotanical knowledge, analyzing how those studies have conceptualized and operationalized ethnobotanical knowledge. We found that this type of research is recent but growing, and is concentrated in indigenous peoples of developing countries. We also found that studies differ on how they conceptualize and measure individual ethnobotanical knowledge. As it is the case in other interdisciplinary research, the lack of conceptual consistency and comparable data limit the inferences that can be drawn from empirical analyses of ethnobotanical knowledge. Future research should 1) validate the consistency of measures of individual ethnobotanical knowledge; 2) analyze the reliability of data generated by the different methods developed so far; and 3) address the relationship between the various dimensions of ethnobotanical knowledge. Studies of individual ethnobotanical knowledge have the potential to contribute to a systematic understanding of humanity’s most widespread and ancient form of knowledge

    How well do foragers protect food consumption? Panel evidence from a native Amazonian society in Bolivia

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    The ability of rural people to protect their food consumption matters because it captures their economic vulnerability. How well do foragers protect consumption from adverse income shocks and does protection work equally well for all people in the household? We answer the queries with data from 156 adults and 169 children collected over five consecutive quarters from the Tsimane', a native Amazonian society of foragers and farmers in Bolivia. We estimate whether quarterly changes in the logarithm of consumption bear an association with quarterly changes in the logarithm of cash income while controlling for many confounders, including covariant shocks. We use anthropometric indices of short-run nutritional status to proxy for food consumption and use instrumental variables to abate biases from the endogeneity of income. We found that child consumption was fully protected from income growth, but adult consumption was not as well protected. Estimates of income elasticities of consumption fell toward the lower range of estimates from previous studies of farming and industrial societies. We present several hypotheses to explain how the Tsimane' smooth consumptio

    The relation between forest clearance and household income among native Amazonians: Results from the Tsimane' Amazonian panel study, Bolivia

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    The Amazon rain forest harbors some of the world's richest biological diversity. During the twentieth century, two types of actors cleared that forest: native Amazonians and outside encroachers. Of the two actors, we know more about what drives outside encroachers to clear forest than about what drives native Amazonians to clear forest. The past research focus has served well because during the twentieth century outside encroachers cleared most of the Amazonian forest. But the past research focus needs to be expanded because native Amazonians are claiming de jure stewardship of the forests they inhabit, and with tighter jurisdiction over those forests will likely come changes in the amount of forest native Amazonians clear. Prior research in rural areas of low-income nations suggests that household income affects household forest clearance. To estimate the effects of household real income on the total forest area (old-growth + fallow) cleared by households we use a panel composed of five annual household surveys (2002–2006, inclusive) from 324 households of a native Amazonian society in Bolivia (Tsimane'). We control for household and village fixed effects and use an instrumental variable for household income. We find positive and significant household real income elasticities of forest clearance of 0.35 and 0.47 and an increase in forest clearance of 5.3%/year. The main finding stood up well to sensitivity analysis. These estimates suggest that in the near future, the forest in the Tsimane' territory will likely face increasing pressure from the Tsimane' themselves, not just from outside encroacher
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