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Cochabamba, Bolivia

Declerck S.A.J.,Netherlands Institute of Ecology | Declerck S.A.J.,Catholic University of Leuven | Coronel J.S.,Higher University of San Simon | Legendre P.,University of Montreal | Brendonck L.,Catholic University of Leuven
Ecography | Year: 2011

Metacommunity structure can be shaped by a variety of processes operating at different spatial scales. With increasing scale, the compositional variation among local communities (beta diversity) may reflect stronger environmental heterogeneity, but may also reflect reduced exchange of organisms between habitat patches. We analyzed the spatial architecture of a metacommunity of cladoceran zooplankton in temporary pools of High Andes wetlands, with the objective of explaining the spatial dependency of its structure. The spatial distribution of the pools is hierarchical and highly discontinuous: pools are clustered within small wetlands, which lay scattered over valleys that are separated from each other by mountain ridges. We studied a total of 59 pools, belonging to six different wetlands in four different valleys. We assessed pool environmental heterogeneity and sampled active communities and dormant propagule banks of cladoceran zooplankton. Environmental heterogeneity proved very high within wetlands and showed almost no increase with increasing spatial scale. Conversely, diversity partitioning analyses indicated an increase in beta diversity with spatial scale, especially among valleys. Variation partitioning on environmental data and spatial RDA models suggested environmental heterogeneity as the most important generator of beta diversity within wetlands. At the largest spatial scale, beta diversity manifested itself mainly as a differentiation of species occurrence patterns among valleys, which could not be entirely explained by environmental variables. Our study thus presents a case where environmental control seems to be the dominant metacommunity structuring process at the smallest spatial scale, whereas neutral processes and dispersal limitation are the most likely generators of beta diversity at the largest spatial scale. © 2011 The Authors. Ecography © 2011 Ecography. Source

de-Miguel S.,University of Eastern Finland | de-Miguel S.,Center Tecnologic Forestal Of Catalonia Ctfc | Guzman G.,Higher University of San Simon | Pukkala T.,University of Eastern Finland
Forest Ecology and Management | Year: 2013

Centrolobium tomentosum is a multipurpose pioneer tree species, indigenous in tropical South America and suitable for forest restoration, agroforestry and plantation systems. Despite its economic and ecological interest, no growth and yield models have been developed for this species so far. Fixed- and mixed-effects modeling can be used in model fitting, each technique having its pros and cons. Marginal predictions can be computed from fixed-effects models or randomized mixed-effects models. In forestry practice, models are seldom calibrated and mixed-effects models are mostly used to provide conditional predictions using only the fixed parameters, assuming that the random effects are zero. This study developed the first set of individual-tree growth and yield models for C. tomentosum and, by using the models, assessed the performance of three prediction approaches: fixed-effects models, conditional predictions of mixed-effects-models and marginal predictions of mixed-effects models. The fitted models predict maximum mean annual bole volume increments of 5.6-16.6m3/ha and optimal rotation lengths ranging from 11 to 21years, depending on site quality. Fixed-effects modeling was the best approach in growth and yield prediction, followed by conditional predictions of mixed-effects models, whereas marginal predictions based on mixed-effects models were in general the least accurate. Fixed-effects models should therefore be preferred in the absence of calibration data. However, since calibration is sometimes a feasible option, research articles should report both fixed- and mixed-effects models in order to enable the computation of the best predictions with and without the possibility of model calibration. © 2012 Elsevier B.V. Source

Ledo C.,Higher University of San Simon | Soria R.,Instituto Nacional Of Salud Publica
Salud Publica de Mexico | Year: 2011

This paper describes the Bolivian health system, including its structure and organization, its financing sources, its health expenditure, its physical, material and humans resources, its stewardship activities and the its health research institutions. It also discusses the most recent policy innovations developed in Bolivia: the Maternal and Child Universal Insurance, the Program for the Extension of Coverage to Rural Areas, the Family, Community and Inter-Cultural Health Model and the cash-transfer program Juana Azurduy intended to strengthen maternal and child care. Source

Zarate M.,Higher University of San Simon
Brittonia | Year: 2016

Two new species of Gentianella, G. quechuana and G. longisepala, are described from the high Andes of Cochabamba, Bolivia. The first new species is characterized by the presence of trichomes inside the corolla tube, 5-veined leaves with papillose margins, pedicels 1–4 cm long, and corolla 2.1–3.5 cm long. These characters distinguish G. quechuana from the most similar species Gentianella kuntzei, G. ruizii, G. nitida, G. longibarbata, and G. amarella. The second new species has an erect herbaceous habit and is 20–50 cm tall, is glabrous inside the corolla, its calyx is 2.4–2.8 cm long with lobes two or more times longer than calyx tube, and its inflorescence has 1–3 flowers. These morphological characters differentiate G. longisepala from very similar species, such as Gentianella bromifolia and G. silenoides (≡Gentiana herzogii). © 2015, The New York Botanical Garden. Source

Cuevas Montilla E.,TU Braunschweig | Hillebrand S.,TU Braunschweig | Antezana A.,Higher University of San Simon | Winterhalter P.,TU Braunschweig
Journal of Agricultural and Food Chemistry | Year: 2011

In nine Bolivian purple corn (Zea mays L.) varieties the content of phenolic compounds as well as the anthocyanin composition has been determined. The phenotypes under investigation included four red and five blue varieties (Kulli, Ayzuma, Paru, Tuimuru, Oke, Huaca Songo, Colorado, Huillcaparu, and Checchi). In purple corn, phenolic compounds were highly concentrated in cell walls. Thus, simultaneous determination of soluble and bound-form phenolics is essential for analysis, extraction, and quantification. The present study reports the determination of soluble and insoluble-bound fraction of phenolic compounds by HPLC-DAD and HPLC-ESI-MS n in Bolivian purple corn varieties. Enzymatic, thermal, and alkaline hydrolyses were used to obtain the cell wall-linked phenolic compounds. Ferulic acid values ranged from 132.9 to 298.4 mg/100 g, and p-coumaric acid contents varied between 251.8 and 607.5 mg/100 g dry weight (DW), respectively, and were identified as the main nonanthocyanin phenolics. The total content of phenolic compounds ranged from 311.0 to 817.6 mg gallic acid equivalents (GAE)/100 g DW, and the percentage contribution of bound to total phenolics varied from 62.1 to 86.6%. The total monomeric anthocyanin content ranged from 1.9 to 71.7 mg cyanidin-3-glucoside equivalents/100 g DW. Anthocyanin profiles are almost the same among the different samples. Differences are observed only in the relative percentage of each anthocyanin. Cyanidin-3-glucoside and its malonated derivative were detected as major anthocyanins. Several dimalonylated monoglucosides of cyanidin, peonidin, and pelargonidin were present as minor constituents. © 2011 American Chemical Society. Source

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