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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
191

Analysis and organization of the family based agricultural production system in the Poroma community of Oropeza province

Burgoa Chopitea, Marco Antonio Domingo 01 January 2000 (has links) (PDF)
This research analyzed the management strategies and organization of crop production in a family agricultural system. This study took place in the Poroma community, Oropeza province, Chuquisaca Department, in Bolivia, at the so called “red zone”, so named for its extreme poverty. The agricultural system used in this study is unique to the pre-puna area of Bolivia and is located in a meso-thermal valley with wet summers. This agricultural system uses a diverse number of native and cultivated plants and animals and incorporates interrelated production strategies in agriculture, animal husbandry, forestry, and crafts. Two important production sectors have been identified in the community: sunny and shady. The four main crops in these sectors are potato, corn, wheat, and barley, with an additional 35 complementary crops. Additionally, 78 crops were identified with specific agronomic and nutritious characteristics. These crops included two used for candy; 56 for human health, and 36 for firewood, wood, dye, and tanning procedures. Limitations with this agricultural system are weak community structural organization, the presence of pests and diseases in crops, and the lack of traditional cultivation practices.
192

Quantification of pollinating insects of the superfamily Apoidea in three ecological niches of three communities in the municipality of Coroico-Nor Yungas, department of La Paz

Claros Sossa, Óscar Jaime 01 January 2008 (has links) (PDF)
The superfamily Apoidea (commonly referred to as bees), are insects whose diet consists of the nectar and pollen from flowering plants. Therefore, they are essential pollinators of many species, both wild and cultivated. Bees are similar to other Hymenoptera in appearance, size, and color variety. The superfamily Apoidea contains 17,000 known species and could possibly contain up to 30,000. Bees perform many tasks that benefit humanity such as pollinating the flowers of both wild and cultivated plants. Without this work, fruits and seeds necessary for the survival of different species, for our own food supply, and for industry would not be able to be produced. The study was done in three communities in the Yungas (Carmen Pampa, San Pablo, and San Juan de la Miel). In each community, three Malaise traps were introduced in three ecological ni ches (Forest, Forest Edge, and Crop Area). Each collection was done every 14 days throughout the six months of winter and spring. The quantification and identification of the Apoidea was conducted in a laboratory through identification keys for families, genera, and species. In total, 83 different morphospecies were identified. In the three communities, a total of 1117 individuals were recorded during the six months of field work. With regard to the niche factor, Partamona sp. (sp2) and Apis mellifera (sp1) were those species that contributed most to the abundance of individuals. In addition, both species contributed to the similarity and dissimilarity seen in the three ecological niches of the three communities. This indicates that they are the most abundant groups within the Yungas forests. They nest primarily in wood, are highly general, are highly social, and are present throughout the year. It is also worth mentioning that the community and station factors do not contribute to the differences in species diversity. Based on the results of this research, a new phase was initiated to identify the species contained within the 83 morphospecies found in the Yungas of La Paz.
193

Determination of four production indicators in llama (Lama glama) herds in Ayllu Pumasara, Saucari, Oruro

Herrera Lopez, Magin 01 January 2004 (has links) (PDF)
Camelid exploitation, despite its economic antiquity in our nation, recently has awakened greater interest in investigators. Currently, there are more than 2,500,000 llamas in the Altiplano, which is the highest number of camelids on the world. Production is organic, with the llama capital of Bolivia being the department of Oruro. This work's objective is to determine four production parameters: composition and structure of llama herds, percentage of births, cria [calf] mortality, and crias that reach 5 months old, in 3 communities of Ayllu Pumasa of Saucar’ province, department of Oruro. The llama-raising system is traditional and herds contain more than 50 llamas per family. Exploitation of llama products still does not have much importance more than commercialization of llama meat in local markets. This study occurred with 9527 llamas from 60 herds, in which the composition of llamas by breed, class, age, and sex was determined, along with birth, mortality, and crias that reached 5 months old, through living in the communities that permitted specialized registration in adequate moments according to the llamas' behavior with families selected for this purpose. The analysis of variance reveals that the communities' composition is highly significant at P<0.01, as well as the communities' behavior, but the interaction between community and composition is not significant (P>0.05). The herds were composed of 26% lone females, 21% nursing females, 21% crias, 16% pregnant females, 13% ancutas, 2% studs, and 1% geldings. In reproductive management, the community does not intervene aside from pasturing in different properties to practice rotation during the rainy season. The breed composition in the communities is highly significant at P>0.01; the herds are of predominantly q'ara stock (42%), with hybrids at 39%, t'ajalli at 13%, and others at 6%. In the age observations, the females (nursing, pregnant, and alone) are animals more than 5 years old. The opposite occurs with the males, which are very young due to the commercialization of high-quality llama meat. Birth rates in the communities are not significant at P<0.01. The average is 34.01% with a 16.58% coefficient of variation. The communities' mortality is significant at P<0.01 between the communities, having an average of 2.58% mortality among llama herds. The variance analysis of crias reaching 5 months old at P<0.01 is not significant. The average was 92.51% in the communities' herds. The llama herds do not totally belong to the families living in the communities. The combined llamas belong to brothers and/or children (who live in the cities), and in some cases the community member is simply a guardian.
194

Food and nutrition situation in the villa Santa Chacoma, Hancara, Hichuraya Grande and Pan de Azucar communities of the Ingavi province in the department of La Paz, Bolivia 1996

Iglesias Sandoval, Teresa Beatriz 01 January 1997 (has links) (PDF)
A diagnosis of the Food and Nutrition situation was made of the populations of the communities of Villa Santa Chacoma, Hancara, Hichuraya Grande and Pan de Azúcar, pertaining to the Ingavi province of the La Paz department. The principle objective was to: identify the Nutritional Food Situation of these communities, the secondary objectives were to: Identify the nutritional state of the inhabitants of the communities, identify the physical availability of food, identify the habits of breastfeeding and supplementary feeding, identify the level of ingestion, establish the consumption of food and identify the level of education of householders; to these ends a cross-sectional descriptive study was designed, with a scope that is limited to the entire population of these communities. The data found in the prevalence of malnutrition in children under 18, according to the indicators of Weight/Age, Weight/Height and Height/Age which are significantly higher. The Global Nutritional State (P/E) presented a 21%, the actual nutritional state (P/T) has a prevalence of 19%; according to the indicator of Height/Age reflecting the nutritional history of child malnutrition showed a prevalence of 32%. These types of malnutrition are expressed more intensely in the male sex and groups of 6 to 17 years. The highest prevalence corresponds to the chronic malnutrition which indicates the under nourishment that children from the earliest years of life and which manifests itself as time goes on.
195

Spacing between rows and plants in two ecotypes of Kanawa (Chenopodium pallidicaule Aellen) in the northern highlands

Marín Parra, Wilfredo Pablo 01 January 2002 (has links) (PDF)
The study "Distance between rows and plants in two ecotypes of canihua (Chenopodium pallidicaule Aellen) in the northern Altiplano" was conducted during the agricultural period of 1999-2000 in the community of Achaca, Tiahuanaco canton, Ingavi province, department of La Paz, Bolivia. It was at 3854 meters above sea level, 16°35' South latitude by 68°41' West longitude. Precipitation was 474.6 mm and the soil was a loose sandy texture. The genetic material was composed of the ecotypes of yellow Lasta, red Lasta, yellow Saihua, and red Saihua, from the Belén Experimental Station, part of the Faculty of Agronomy, San Andrés Higher University. With the objective to evaluate the effect of distance between rows and between plants on the agronomic behavior of two ecotypes of Canihua in the northern Altiplano, planting took place on December 20, 1999, in rows 20, 40, and 60 cm apart, at a density of 4 kg/ha, all of it under a random block design with plots sub-subdivided. The principal plot set the distance between rows, the subplot set the distance between plants, and the sub-subplot the different ecotypes. Thirty-five days after planting the plants were thinned by hand, and with the use of a cord they were located at pre-established distances of 10, 20, and 30 cm between plants. The effects of the different distances on the ecotypes gave the following results and principal conclusions: The height and stem width of canihua was directly proportional to the different distances between plants and rows, and inversely proportional to the number of plants per area. The maximum values reached for height (21.4 cm) and diameter (2.5mm) occurred with 60 cm between rows and 101,852 plants per hectare. Also, the yellow Saihua ecotype was taller than the rest of the ecotypes at 19.1 cm. As for diameter, the ecotypes presented statistically similar behavior.
196

Study of Two Species of Bees (Apis mellifica) and Three Types of Beehives In and Around Chulumani (Prov. Chapare)

Pardo, Jose Cruz 01 January 2000 (has links) (PDF)
In order to improve the diet of the comunarios of Chulumani, and to expect a better production of honeybee; it has been introduced the Apis mellífica cárnica queen in Apis mellífica scutellata colonies. It was also carried out comparative tests among beehives Langstroth, Schirmer and Dadant. The nucleus “S” was only used as an introduction of queens, and the nucleus “M” and “K” were utilized for the development of the colony (submúltiplos of the beehive Schirmer). The study was carried out totally at random with the experimental design with factorial arrangement, and the meaning of the comparative analysis it was determined by the test of Dunnett. As a result of the substitution of queens more docile colonies were obtained with yields of honey of 22-26 Kg/beehive; being the beehive Schirmer the one that gathered the best size, weight and geometric space similar to which the bees develop in natural form. This way, it has been obtained a technically and economically viable beekeeping with carniolan bees in beehives Schirmer.
197

Analysis of genetic variability of quinoa (Chenopodium quinoa Wild.) germ plasm around Lake Titicaca

Pinto Porcel, Milton Víctor 01 January 2002 (has links) (PDF)
With the goal of analyzing the genetic variability of quinoa (Chenopodium quinoa Willd) germ plasm around Lake Titicaca, which is conserved in the National Bank of High Andean Grains of the PROINPA Altiplano Regional Foundation, the agromorphological behavior of 432 quinoa samples from the surrounding area (both Bolivian and Peruvian) were characterized and evaluated. This activity occurred at agricultural step 99/2000 of Belén Agricultural Station (16°1' South by 68°42' West), with the San Andrés Higher University Faculty of Agronomy, which because of its proximity to the lake represents climate conditions like those of the studied material's origin. In order to determine standards of genetic variation, identify the most discriminating quantitative variables, and classify sample groups of different genetic variability, two multivariate methods were applied using 17 quantitative variables: 5 phenotypic, 10 morphological, yield, and harvest index. The descriptive statistical analysis showed a wide genetic variability regarding the phenologic cycle and the size of the quinoa plants. According to the simple correlation analysis, the most important associations between phenologic variables corresponded to 50% of flowering at the beginning and end of flowering. The morphological variables highlight associations between leaf width with leaf length and stalk length. Likewise, the associations between yield and stem diameter, length of the grain bunch, diameter of the grain bunch, and plant height are statistically significant. All of these are positively associated with the other phenotypic variables. The architecture of the plant, in contrast, negatively influenced the yield and harvest index. The analysis of principle components identified 4 significant components that contributed more than 69% of total variance. The first principal component identified tall plants with thick stems, with large leaves and grain bunches, but with a late phenologic cycle and, as such, with low harvest indexes. The second principal component identified early plants of medium size that tend to develop relatively thick stems, with medium leaves, grain bunches and good-quality grain. Consequently, they produced the best yield. Similarly, the proportion of total variance contributed by each variable over the 4 significant components was determined. It was found that the most important and discriminating variables were 50% flowering, flowering index, and end of flowering, followed by weight of 100 grains, grain diameter, yield, and finally the length of the grain bunch, length of leaves, stem diameter, and leaf width. A non-hierarchical K-medium grouping technique permitted the classification of quinoa samples around Lake Titicaca in two groups. Group 1 consisted of 161 late quinoa plants with tall heights, large grain bunches, and low harvest indexes. Group 2 consisted of 271 early quinoa plants of medium size, leaves, and grain bunches, with small grains that at the same time have high harvest indexes.
198

Evaluation of hair production in angora rabbits (Oryctolagus cuniculus), fed with three different rations of reed in the Desaguadero municipality - department of La Paz

Sullca Mamani, Angel 01 January 2007 (has links) (PDF)
This study was carried out in the Azafranal community of the Desaguadero municipality, which is in the Ingavi Province of the Department of La Paz. It was conducted at an altitude of 3350 meters above sea level at 16°20’00” south latitude and 69°00’00” west longitude. The study went from December 20, 2003 to June 20, 2004. Our objective was to evaluate hair production in angora rabbits (Oryctolagus cuniculus) fed with three different rations of reed. The experimental trial was done at the Angorita farm over a 135 day period that was divided into three smaller periods of 45 days. The experiment was done via a completely randomized block design. The means from each treatment (A, B, C, and D) were analyzed by a Duncan test with a level of 95% confidence. The population consisted of 16 male and 16 female English angora rabbits between 90 and 98 days of age. These were divided into four groups of eight individuals. Each group was then subjected to one of four treatments: 1) ration A with 40% reed content, 2) ration B with 30% reed content, 3) ration C with 20% reed content, and 4) ration D as a control with 0% reed content. The variables measured and studied were: hair weight (g), hair diameter (µ), hair length (cm), and length of a lock of hair (cm). The results reflect a positive effect on hair diameter with rations C and A, which had average diameters of 9.48 µ and 9.64 µ respectively. Furthermore, with respect to hair length, ration A had an average of 4.87 cm and ration C had an average of 4.68 cm. Lastly, with respect to length of a lock of hair, ration A had an average of 4.74 cm and ration B had an average of 4.52 cm (P0.05).
199

Brucellosis in alpacas (Lama pacos) in communities of the city Ulla Ulla, Franz Tomayo province, department of La Paz

Suxo Blanco, Macario 01 January 2005 (has links) (PDF)
This investigation was performed in the Altiplano Altoandino sub-humid region in the Ulla Ulla district, Pelechuco township, Franz Tomayo province, department of La Paz, Bolivia. The objective of this study was to quantify and compare the presence of Brucellosis in male and female alpacas (Lama pacos) at ages 2, 3, 4, 5, 6, and 7 years. Blood samples were taken from the jugular vein of 500 alpacas from the Hichucollo, Huacuchani, Ucha Ucha, and Ulla Ulla communities. The serum from each sample was separated and a serological diagnosis was performed by rapid agglutination with Rose Bengal chemical stain. In the Ulla Ulla district, 11.0% of alpacas were suspected of being infected. Of that 11.0%, 9.6% represented female alpacas while the remaining 1.4% represented male alpacas. By community, the overall results were 0.6%, 0.2%, 7.4%, and 2.8% for Hichucollo, Huacuchani, Ucha Ucha, and Ulla Ulla respectively. With regards to gender in each community, 1.4%, 1.6%, 13.3%, and 11.1% of female alpacas and 2.7%, 0.0%, 1.2%, and 1.9 % of male alpacas were suspected of being infected in Hichucollo, Huacuchani, Ucha Ucha, and Ulla Ulla, respectively. According to age, 0.8%, 2.6%, 3.8%, 2.0%, 11.8%, and 0.0% were suspected of Brucellosis in alpacas 2, 3, 4, 5, 6, and 7 years old, respectively in the Ulla Ulla district. The analysis of variance among the results does not present significant differences (p ≥ 0.05), failing to reject the given hypothesis. The final prevalence point found in the Ulla Ulla district was 11.0%. It was concluded that the prevalence of suspected cases of Brucellosis in alpacas is a consequence of the antigenic characteristics of each biotype. Furthermore, the results affirm that the poor management of livestock and livestock health lead to significant problems with alpaca health. It is therefore necessary to implement control strategies as well as disease monitoring in communities by following a detailed program of diagnostic tests for Brucellosis. Also, non-infected flocks must be protected against infection.
200

Introducing Lesser-Known Wood Species from Certified Forests in Bolivia to the U.S. Market

Cossio Antezana, Victor H. 20 September 2007 (has links)
A nationwide mail survey was conducted among importers and other members of the supply chain linked to the importation of tropical hardwood products to assess the market potential for Bolivian lesser-known wood species (LKS) in the U.S. market. One hundred and eleven companies responded to the questionnaire and provided information on their interest in importing lesser-known wood species, their willingness to pay for a Bolivian wood species substitute, percentage of their imports that are environmentally certified, and important factors considered to try new wood species. The results indicate that tropical hardwoods represent 33% of the product mix of companies that purchased wood products. Typically, companies imported less than 100 MBF in 2006. Sawnwood was the product that was imported the most, followed by plywood, veneer and flooring. Six Bolivian LKS are among the top 16 new wood species purchased by respondent companies in 2006 and three Bolivian LKS are part of the top 12 common tropical wood species imported in the U.S. Sixty-seven percent of overall respondents stated that they have plans to increase the imports of tropical hardwoods in 2007. Typically, members of the supply chain tried 1 to 2 new wood species in 2006. Retailers were the sector that tried the most, on average 5 new species. Price and availability were the major reasons to try new wood species. A MS-Access database was developed that allows comparisons of 20 potentially marketable Bolivian LKS with 10 common U.S. domestic hardwoods and 20 common tropical hardwoods imported into the U.S. Finally, strategic marketing recommendations are suggested to promote Bolivian LKS in the U.S. Results indicate that there are good opportunities for Bolivian LKS in the U.S market. / Master of Science

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