Papers by Jose Blancas Vazquez
Background: Management types and their intensity may vary according to indicators such as: (1) pr... more Background: Management types and their intensity may vary according to indicators such as: (1) practices complexity, (2) degree of techniques specialization, (3) occurrence and types of social regulations, (4) artificial selection intensity, (5) energy invested, (6) tools types, and (7) amounts of resources obtained. Management types of edible plants were characterized and analyzed in Náhuatl communities of the Tehuacán Valley. We expected that both natural and human pressures generate risk on plant resources availability, influencing human responses of management directed to decrease risk. We particularly hypothesized that magnitude of risk would be a direct function of human pressures favored by cultural and economic value and ecological factors such as scarcity (restricted distribution and abundance). Management practices may decrease risk of plant resources, more effectively when they are more intense; however, absence or insufficiency of management practices on endangered plants may favor loss of their populations. Understanding current management motives and their consequences on the purpose of ensuring availability of plant resources might allow us to understand similar processes occurring in the past. This issue is particularly important to be studied in the Tehuacán Valley, where archaeologists documented possible scenarios motivating origins of plant management by agriculture during prehistory. Methods: Through ethnobotanical collecting, 55 semi-structured and free listing interviews we inventoried edible plant species used in five villages of Coyomeapan, Mexico. We identified: (1) native plant species whose products are obtained exclusively through simple gathering, (2) native species involving simple gathering and other management types, and (3) non-native species managed by agricultural management. We conducted in depth studies on the 33 native species managed through gathering and other types of practices. We carried out a total of 660 sessions of detailed interviews to 20 households randomly selected. We showed to people voucher specimens and photos of the sample of species chosen and documented their cultural and economic values. Spatial availability of these plant species was evaluated through vegetation sampling. Values for each cultural, economic, and ecological indicator were codified and averaged or summed and weighed according to frequency of interviewees' responses or ecological conditions per plant species. With the standardized values of these indicators we performed a PCA and scores of the first principal component were considered as a risk index, which summarizes information of thirteen indicators of human use, demand and scarcity of each plant species. Similarly, eleven indicators of energy invested, complexity, tools and management strategies were used for performing PCA and scores of the first principal component were considered as management intensity index for each plant species. A linear regression analysis was performed to analyze the relation between risk and management intensity indexes. Amounts of variation of management data explained by ecological, cultural and economic information, as well as their risk level were analyzed through canonical correspondence analyses (CCA).
Background: Management types and their intensity may vary according to indicators such as: (1) pr... more Background: Management types and their intensity may vary according to indicators such as: (1) practices complexity, (2) degree of techniques specialization, (3) occurrence and types of social regulations, (4) artificial selection intensity, (5) energy invested, (6) tools types, and (7) amounts of resources obtained. Management types of edible plants were characterized and analyzed in Náhuatl communities of the Tehuacán Valley. We expected that both natural and human pressures generate risk on plant resources availability, influencing human responses of management directed to decrease risk. We particularly hypothesized that magnitude of risk would be a direct function of human pressures favored by cultural and economic value and ecological factors such as scarcity (restricted distribution and abundance). Management practices may decrease risk of plant resources, more effectively when they are more intense; however, absence or insufficiency of management practices on endangered plants may favor loss of their populations. Understanding current management motives and their consequences on the purpose of ensuring availability of plant resources might allow us to understand similar processes occurring in the past. This issue is particularly important to be studied in the Tehuacán Valley, where archaeologists documented possible scenarios motivating origins of plant management by agriculture during prehistory. Methods: Through ethnobotanical collecting, 55 semi-structured and free listing interviews we inventoried edible plant species used in five villages of Coyomeapan, Mexico. We identified: (1) native plant species whose products are obtained exclusively through simple gathering, (2) native species involving simple gathering and other management types, and (3) non-native species managed by agricultural management. We conducted in depth studies on the 33 native species managed through gathering and other types of practices. We carried out a total of 660 sessions of detailed interviews to 20 households randomly selected. We showed to people voucher specimens and photos of the sample of species chosen and documented their cultural and economic values. Spatial availability of these plant species was evaluated through vegetation sampling. Values for each cultural, economic, and ecological indicator were codified and averaged or summed and weighed according to frequency of interviewees' responses or ecological conditions per plant species. With the standardized values of these indicators we performed a PCA and scores of the first principal component were considered as a risk index, which summarizes information of thirteen indicators of human use, demand and scarcity of each plant species. Similarly, eleven indicators of energy invested, complexity, tools and management strategies were used for performing PCA and scores of the first principal component were considered as management intensity index for each plant species. A linear regression analysis was performed to analyze the relation between risk and management intensity indexes. Amounts of variation of management data explained by ecological, cultural and economic information, as well as their risk level were analyzed through canonical correspondence analyses (CCA).
Background: The Tehuacán Valley, Mexico is a region with exceptionally high biocultural richness.... more Background: The Tehuacán Valley, Mexico is a region with exceptionally high biocultural richness. Traditional knowledge in this region comprises information on nearly 1,600 plant species used by local peoples to satisfy their subsistence needs. Plant resources with higher cultural value are interchanged in traditional markets. We inventoried the edible plant species interchanged in regional markets documenting economic, cultural and ecological data and about their extraction and management in order to: (1) assess how commercialization and ecological aspects influence plant management, (2) identify which species are more vulnerable, and (3) analyze how local management contributes to decrease their risk. We hypothesized that scarcer plant species with higher economic value would be under higher pressure motivating more management actions than on more abundant plants with lower economic value. However, construction of management techniques is also influenced by the time-span the management responses have taken as well as biological and ecological aspects of the plant species that limit the implementation of management practices. Plant management mitigates risk, but its absence on plant species under high risk may favor local extinction. Methods: Six traditional markets were studied through 332 semi-structured interviews to local vendors about barter, commercialization, and management types of local edible plant species. We retrieved ethnobotanical information on plant management from ten communities in a workshop and sampled regional vegetation in a total of 98 sites to estimate distribution and abundance of plant species commercialized. Through Canonical Correspondence Analysis (CCA) we analyzed the amount of variation of management types that can be explained from socioeconomic and ecological information. A risk index was calculated relating distribution, abundance, economic value and management of plant resources to identify the most vulnerable species.
Background: The Peruvian Andean region is a main center of plant domestication of the world. Ther... more Background: The Peruvian Andean region is a main center of plant domestication of the world. There, several tuber species were domesticated and the area lodges one of the most important reservoirs of their varieties and wild relatives. It is also the setting of traditional cultures using and conserving them. However, crop genetic erosion has been reported in the region since several decades ago; therefore, understanding factors influencing both loss and maintenance of crop variation is relevant to design conservation policies. Previous researches have examined factors influencing agrobiodiversity conservation in the region but additional case studies are recognized to be still necessary for a deeper understanding of causes of genetic erosion and for policy design to prevent and remedy it. Our study focused on analyzing (1) variation in richness of traditional varieties of tubers cultivated among households, (2) changes in varieties richness occurred in four consecutive agricultural cycles, and (3) ecological, social, and cultural factors influencing loss and conservation of varieties.
Economic Botany, 2010
Plant Management in the Tehuacán-Cuicatlán Valley, Mexico. Plant management types currently pract... more Plant Management in the Tehuacán-Cuicatlán Valley, Mexico. Plant management types currently practiced in the Tehuacán-Cuicatlán Valley, México, were documented and analyzed based on ethnobotanical studies conducted in 13 villages with six indigenous groups and Mestizo people. The information was organized in a data base, and then detailed and guided to a consensus through six workshops carried out by ethnobotanists working in the area. From a total of 1,608 useful plant species, we identified 610 with at least one management type other than simple gathering. Managed species are mainly used as food, fodder, medicinal, and ornamental, and they belong to 101 plant families. The higher species numbers were recorded in Cactaceae, Asteraceae, Fabaceae, Crassulaceae, and Agavaceae. Nearly 60% of the managed species are native to the region and the rest are introduced from other regions of Mexico and the world. In total, 400 species are ex situ managed out of their natural environments through seed sowing and/or planting their vegetative propagules or entire young plants; 373 species are in situ managed in their natural habitats as follows: all these species are deliberately left standing during vegetation clearance, 76 species are also enhanced intentionally favoring their abundance through modifications of their habitat, or directly by planting their propagules, and 51 receive protection through regulations, particular strategies of extraction, and actions against herbivores, competitors, freezing, radiation, and drought. Most management forms involve artificial selection at different intensity levels. The information allows visualizing co-occurrence of incipient and advanced forms of management at different intensity levels within and among species, which helps to postulate testable hypotheses on factors influencing plant management and domestication in an important area for studying the origins of agriculture.
Journal of Ethnobiology and Ethnomedicine, 2013
Background: Management types and their intensity may vary according to indicators such as: (1) pr... more Background: Management types and their intensity may vary according to indicators such as: (1) practices complexity, (2) degree of techniques specialization, (3) occurrence and types of social regulations, (4) artificial selection intensity, (5) energy invested, (6) tools types, and (7) amounts of resources obtained. Management types of edible plants were characterized and analyzed in Náhuatl communities of the Tehuacán Valley. We expected that both natural and human pressures generate risk on plant resources availability, influencing human responses of management directed to decrease risk. We particularly hypothesized that magnitude of risk would be a direct function of human pressures favored by cultural and economic value and ecological factors such as scarcity (restricted distribution and abundance). Management practices may decrease risk of plant resources, more effectively when they are more intense; however, absence or insufficiency of management practices on endangered plants may favor loss of their populations. Understanding current management motives and their consequences on the purpose of ensuring availability of plant resources might allow us to understand similar processes occurring in the past. This issue is particularly important to be studied in the Tehuacán Valley, where archaeologists documented possible scenarios motivating origins of plant management by agriculture during prehistory. Methods: Through ethnobotanical collecting, 55 semi-structured and free listing interviews we inventoried edible plant species used in five villages of Coyomeapan, Mexico. We identified: (1) native plant species whose products are obtained exclusively through simple gathering, (2) native species involving simple gathering and other management types, and (3) non-native species managed by agricultural management. We conducted in depth studies on the 33 native species managed through gathering and other types of practices. We carried out a total of 660 sessions of detailed interviews to 20 households randomly selected. We showed to people voucher specimens and photos of the sample of species chosen and documented their cultural and economic values. Spatial availability of these plant species was evaluated through vegetation sampling. Values for each cultural, economic, and ecological indicator were codified and averaged or summed and weighed according to frequency of interviewees' responses or ecological conditions per plant species. With the standardized values of these indicators we performed a PCA and scores of the first principal component were considered as a risk index, which summarizes information of thirteen indicators of human use, demand and scarcity of each plant species. Similarly, eleven indicators of energy invested, complexity, tools and management strategies were used for performing PCA and scores of the first principal component were considered as management intensity index for each plant species. A linear regression analysis was performed to analyze the relation between risk and management intensity indexes. Amounts of variation of management data explained by ecological, cultural and economic information, as well as their risk level were analyzed through canonical correspondence analyses (CCA).
Journal of Ethnobiology and Ethnomedicine, 2013
Background: The Tehuacán Valley, Mexico is a region with exceptionally high biocultural richness.... more Background: The Tehuacán Valley, Mexico is a region with exceptionally high biocultural richness. Traditional knowledge in this region comprises information on nearly 1,600 plant species used by local peoples to satisfy their subsistence needs. Plant resources with higher cultural value are interchanged in traditional markets. We inventoried the edible plant species interchanged in regional markets documenting economic, cultural and ecological data and about their extraction and management in order to: (1) assess how commercialization and ecological aspects influence plant management, (2) identify which species are more vulnerable, and (3) analyze how local management contributes to decrease their risk. We hypothesized that scarcer plant species with higher economic value would be under higher pressure motivating more management actions than on more abundant plants with lower economic value. However, construction of management techniques is also influenced by the time-span the management responses have taken as well as biological and ecological aspects of the plant species that limit the implementation of management practices. Plant management mitigates risk, but its absence on plant species under high risk may favor local extinction. Methods: Six traditional markets were studied through 332 semi-structured interviews to local vendors about barter, commercialization, and management types of local edible plant species. We retrieved ethnobotanical information on plant management from ten communities in a workshop and sampled regional vegetation in a total of 98 sites to estimate distribution and abundance of plant species commercialized. Through Canonical Correspondence Analysis (CCA) we analyzed the amount of variation of management types that can be explained from socioeconomic and ecological information. A risk index was calculated relating distribution, abundance, economic value and management of plant resources to identify the most vulnerable species. * These variables were recategorized and were considered as another variable because some plant species had more than one value in this category. Values were summed in the recategorized variables.
Plant Management in the Tehuacán-Cuicatlán Valley, Mexico. Plant management types currently pract... more Plant Management in the Tehuacán-Cuicatlán Valley, Mexico. Plant management types currently practiced in the Tehuacán-Cuicatlán Valley, México, were documented and analyzed based on ethnobotanical studies conducted in 13 villages with six indigenous groups and Mestizo people. The information was organized in a data base, and then detailed and guided to a consensus through six workshops carried out by ethnobotanists working in the area. From a total of 1,608 useful plant species, we identified 610 with at least one management type other than simple gathering. Managed species are mainly used as food, fodder, medicinal, and ornamental, and they belong to 101 plant families. The higher species numbers were recorded in Cactaceae, Asteraceae, Fabaceae, Crassulaceae, and Agavaceae. Nearly 60% of the managed species are native to the region and the rest are introduced from other regions of Mexico and the world. In total, 400 species are ex situ managed out of their natural environments through seed sowing and/or planting their vegetative propagules or entire young plants; 373 species are in situ managed in their natural habitats as follows: all these species are deliberately left standing during vegetation clearance, 76 species are also enhanced intentionally favoring their abundance through modifications of their habitat, or directly by planting their propagules, and 51 receive protection through regulations, particular strategies of extraction, and actions against herbivores, competitors, freezing, radiation, and drought. Most management forms involve artificial selection at different intensity levels. The information allows visualizing co-occurrence of incipient and advanced forms of management at different intensity levels within and among species, which helps to postulate testable hypotheses on factors influencing plant management and domestication in an important area for studying the origins of agriculture.
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Papers by Jose Blancas Vazquez