Browsing by Autor "Alejandra I. Domic"

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Allometry and effects of extreme elevation on growth velocity of the Andean tree Polylepis tarapacana Philippi (Rosaceae)
(Springer Science+Business Media, 2009) Alejandra I. Domic; José M. Capriles
Carbon dynamics in high‐<scp>A</scp>ndean tropical cushion peatlands: A review of geographic patterns and potential drivers
(Wiley, 2024) Mary Carolina García Lino; Simon Pfanzelt; Alejandra I. Domic; Isabell Hensen; Karsten Schittek; Rosa Isela Meneses; Maaike Y. Bader
Abstract Peatlands store large amounts of carbon (C), a function potentially threatened by climate change. Peatlands composed of vascular cushion plants are widespread in the northern and central high Andes (páramo, wet and dry puna), but their C dynamics are hardly known. To understand the interplay of the main drivers of peatland C dynamics and to infer geographic patterns across the Andean regions, we addressed the following question: How do topography, hydrology, temperature, past climate variability, and vegetation influence the C dynamics of these peatlands? We summarize the available information on observed spatial and inferred temporal patterns of cushion peatland development in the tropical and subtropical Andes. Based on this, we recognize the following emerging patterns, which all need testing in further studies addressing spatial and temporal patterns of C accumulation: (1) Peatlands in dry climates and those in larger catchments receive higher sediment inputs than peatlands from wet puna and páramo and in small catchments. This results in peat stratigraphies intercalated with mineral layers and affects C accumulation by triggering vegetation changes. (2) High and constant water tables favor C accumulation. Seasonal water level fluctuations are higher in wet and dry puna, in comparison with páramo, leading to more frequent episodes of C loss in puna. (3) Higher temperatures favor C gain under high and constant water availability but also increase C loss under low and fluctuating water levels. (4) C accumulation has been variable through the Holocene, but several peatlands show a recent increase in C accumulation rates. (5) Vegetation affects C dynamics through species‐specific differences in productivity and decomposition rate. Because of predicted regional differences in global climate change manifestations (seasonality, permafrost behavior, temperature, precipitation regimes), cushion peatlands from the páramo are expected to mostly continue as C sinks for now, whereas those of the dry puna are more likely to turn to C sources as a consequence of increasing aridification.
Climate change and the distribution and conservation of the world's highest elevation woodlands in the South American Altiplano
(Elsevier BV, 2015) Griet An Erica Cuyckens; Duncan A. Christie; Alejandra I. Domic; Lucio R. Malizia; Daniel Renison
Eliana Flores Bedregal (1954 - 2017): Ornitóloga y conservacionista boliviana
(2017) José M. Capriles; Alejandra I. Domic
ENSAMBLES DE AVES DE LOS BOSQUES ENDEMICOS DE POLYLEPIS PACENSIS EN BOLIVIA
(2019) Isabel María Gómez Barreto; Rodrigo Calbimonte; Alejandra I. Domic; Arely N. Palabral-Aguilera; Rosember Hurtado; Máximo Liberman
Resumen ∙ Los bosques de Polylepis pacensis son endémicos de Bolivia y se distribuyen en los departamentos de La Paz (inmediaciones al nevado Illimani, Quime e Inquisivi) y Cochabamba (Cotacajes). En este estudio, se evaluó el ensamble de aves en cuatro fragmentos de bosque de P. pacensis ubicados en las faldas del nevado Illimani, La Paz, Bolivia. En estos fragmentos de bosque se observaron 31 especies de aves, incluyendo dos especies endémicas de Bolivia, Colibrí Negrito (Aglaeactis pamela) y Pinchaflor Carbonero (Diglossa carbonaria), y dos especies fuertemente especializadas a bosques de Polylepis, Tijeral de Yánac (Leptasthenura yanacensis) y Conirrostro Gigante (Conirostrum binghami). Los bosques de Polylepis pacensis están altamente amenazados por actividades humanas como quema, extracción de leña y agricultura; las cuales podrían estar causando la deforestación y degradación de este importante hábitat para las aves. Es crucial implementar programas de conservación que incluyan la participación activa de la población local.Abstract ∙ Bird assemblages in endemic Polylepis pacensis woodlands in Bolivia Polylepis pacensis woodlands are endemic to Bolivia, distributed in La Paz (near Illimani, Quime, and Inquisivi) and Cochabamba (Cotacajes) departments. In this study, we evaluated the bird assemblages of four fragments of P. pacensis woodlands located in the foothills of nevado Illimani, La Paz, Bolivia. In these woodlands, we recorded 31 bird species, including two endemic species of Bolivia, Black-hooded Sunbeam (Aglaeactis pamela) and Grey-bellied Flowerpiercer (Diglossa carbonaria), and two species strongly specialized to Polylepis woodlands, Tawny Tit-spinetail (Leptasthenura yanacensis) and Giant Conebill (Conirostrum binghami). Polylepis pacensis woodlands are highly threatened by human activities, such as burning, logging and agriculture; which may be causing of deforestation and degradation of this important habitat for bird species. It is crucial to implement conservation programs involving the active participation of local people.
Estudios etnobotánicos y florísticos de los bosques amenazados de Polylepis incarum y Polylepis pacensis (Rosaceae) en Bolivia
(Instituto de Botánica del Nordeste, 2018) Rosember Hurtado; Arely N. Palabral-Aguilera; Alejandra I. Domic; María Isabel Vargas; Máximo Liberman
Los bosques de Polylepis (Rosaceae) constituyen hábitats importantes para la flora y fauna altoandina y proveen servicios ecosistémicos directos a las comunidades indígenas. Sin embargo, existen pocos relevamientos florísticos así como estudios etnobotánicos en estos ecosistemas boscosos. Evaluamos la composición florística, los usos socioeconómicos de las especies y la valoración local sobre los bosques de P. pacensis y P. incarum en los Andes occidentales bolivianos. Registramos un total de 46 especies de plantas en los bosques de P. pacensis y 58 especies en los bosques de P. incarum. Cada uno incluye dos especies endémicas, respectivamente, Aa trilobulata y Calceolaria bartsiifolia, e Hieracium padcayense y Calceolaria bartsiifolia. En total 13 especies medicinales son utilizadas para tratar una variedad de enfermedades. Las comunidades indígenas locales utilizan Polylepis como combustible, medicina, material de construcción y poseen un importante valor ritual. El 54% de los entrevistados mencionaron que la cobertura de P. pacensis se mantuvo durante los últimos 10 años; mientras que el 44% de los entrevistados consideró que los bosques de P. incarum aumentaron y el 40% consideró que éstos disminuyeron. Se precisan programas de conservación que involucren la participación activa de las comunidades indígenas locales, paramejorar la valoración de estos ecosistemas boscosos
Evaluating the fitness effects of seed size and maternal tree size onPolylepis tomentella(Rosaceae) seed germination and seedling performance
(Cambridge University Press, 2020) Alejandra I. Domic; José M. Capriles; Gerardo R. Camilo
Abstract In vascular plants, larger seeds are generally associated with higher germination potential, healthier seedlings and overall higher rates of survivorship. How this relationship holds or what other physiological tradeoffs evolved in plants adapted to high-altitude environments, such as the tropical and subtropical highland Polylepis tree, remain unclear. In this study, we evaluated the relationship between seed mass and seedling performance by testing the reserve effect, the metabolic effect, and the seedling-size effect hypotheses in Polylepis tomentella Weddell (Rosaceae). Since the relationship between fitness and seed size can often depend on maternal plant size, we additionally investigated the association between germination success, seedling performance (survival, relative growth rate (RGR) and height), and size of bearing-seed trees under controlled greenhouse conditions. Our results showed that heavier seeds are more likely to germinate, but we did not find evidence that could support the reserve effect, metabolic effect or seedling-size effect. As seedlings from larger and medium seeds exhibited comparatively similar RGR, survival percentages and final size, maternal plant size was positively associated with improved seed quality and seedling performance. These results demonstrate that seed mass and maternal size during early seedling establishment are critical for Polylepis persistence, demography and conservation.
Fenología reproductiva de la kewiña (Polylepis tomentella, Rosaceae) en la puna semihúmeda de Chuquisaca (Bolivia)
(2013) Alejandra I. Domic; Evelina Mamani; Gerardo R. Camilo
Fenología reproductiva de la queñua (Polylepis incarum, Rosaceae) durante un ciclo anual en la puna mesofítica de La Paz, Bolivia
(2018) Cecilia L. López Alipaz; Alejandra I. Domic; César Mayta; Emilia García; Silvia C. Gallegos
In this study, the phenology of queñua (Polylepis incarum, Rosaceae) was evaluated during an annual cycle in the mesophytic puna of La Paz. The species is endemic to the Lake Titicaca basin. Like other species of the genus Polylepis, P. incarum is categorized as Endangered for Bolivia due to anthropic activities as firewood extraction and crop expansion. During one year (March 2015 - February 2016), we conducted monthly evaluations in a woodland located in the community of Kopacati, Copacabana department, La Paz, Bolivia. The objectives of the study were to identify flowering and fruiting times, and to assess the relationships between plant size, environmental factors and plant reproductive success. The species produces floral buds between July and August. The production of flowers in the female state occurs between July and November, and flowers in the male state, between July and October. The highest production of immature fruits took place in November, reaching maturity in December and January. Both precipitation and temperature showed a significant influence on flowers and fruits production. Diameter at breast height (DBH) was the only allometric character significantly associated to the production of flowers and fruits between trees and shrubs. There was no significant difference in the production of flowers and fruits between trees and shrubs. The phenological patterns informed for this species are similar those reported for P. tomentella and P. besseri. The results of the present study contribute to the knowledge about the reproductive biology of Polylepis incarum and to promote programs of conservation and reforestation of the species.https://doi.org/10.25260/EA.18.28.1.1.516
Fishing and environmental change during the emergence of social complexity in the Lake Titicaca Basin
(Elsevier BV, 2014) José M. Capriles; Katherine M. Moore; Alejandra I. Domic; Christine A. Hastorf
High-altitude adaptation and late Pleistocene foraging in the Bolivian Andes
(Elsevier BV, 2016) José M. Capriles; Juan Albarracín-Jordán; Umberto Lombardo; Daniela Osorio; Blaine Maley; Steven T. Goldstein; Katherine Herrera; Michael D. Glascock; Alejandra I. Domic; Heinz Veit
Local Management of Andean Wetlands in Sajama National Park, Bolivia
(International Mountain Society, 2014) Elena Katia Villarroel; Paula Lady Pacheco Mollinedo; Alejandra I. Domic; José M. Capriles; Carlos Espinoza
Andean wetlands or bofedales are commonly used by indigenous communities for livestock production. Decisions regarding management of bofedales involve the active participation of local people and their social institutions. Consequently, any action addressing emerging challenges must be implemented in coordination and agreement with local actors. This decision process requires an understanding of the local socioeconomic and cultural dynamics, especially those related to land and natural resource management. In many Andean communities, the ayllu is the institution that governs decisions on regional land use. However, in the face of increasing challenges such as climate change and population growth, use of the ayllu has declined in favor of individual decision-making. Here we discuss how the Andean camelid herders of Sajama National Park in highland Bolivia rely on both the ayllu and family-level decision-making to manage their pastoralist landscapes, including their bofedales. Using a rights mapping methodology, we describe how water and wetlands are managed, and determine which decisions are taken at the community level and which are made at the family level. We conclude that indigenous collective organization networks are still significant for managing the system at a regional scale and possibly determinant for mitigating risks associated with climate change on sensitive ecosystems such as bofedales.
Phylogenetic placement of Leptosphaeria polylepidis, a pathogen of Andean endemic Polylepis tarapacana, and its newly discovered mycoparasite Sajamaea mycophila gen. et sp. nov.
(Springer Science+Business Media, 2020) Marcin Piątek; Pamela Rodriguez‐Flakus; Alejandra I. Domic; Arely N. Palabral-Aguilera; María Isabel Gómez; Adam Flakus
Abstract Polylepis tarapacana forms one of the highest-altitude woodlands worldwide. Its populations are experiencing a decline due to unsustainable land-use practices, climate change, and fungal infection. In Sajama National Park in Bolivia, Polylepis tarapacana is affected by a disease caused by the pleosporalean fungus Leptosphaeria polylepidis , recently described in 2005. In this study, the integrative morphological and molecular analyses using sequences from multiple DNA loci showed that it belongs to the genus Paraleptosphaeria (Leptosphaeriaceae, Pleosporales). Accordingly, the appropriate new combination, Paraleptosphaeria polylepidis , is made. Pseudothecia of Pa. polylepidis were found to be overgrown by enigmatic conidiomata that were not reported in the original description of this fungus. Morphological and molecular analyses using sequences from two DNA loci revealed that they belong to an undescribed genus and species in the family Dictyosporiaceae (Pleosporales). The new generic and specific names, Sajamaea and S. mycophila , are introduced for this unusual fungus.
Plant community assembly is predicted by an environmental gradient in high-altitude wetlands in the semiarid western Bolivian Andes
(International Mire Conservation Group and International Peat Society, 2021) Alejandra I. Domic; José M. Capriles; Rosa Isela Meneses; Paula Pacheco; Rosa Isela Meneses; Universidad Católica del Norte, Programa de Doctorado en Antropología, San Pedro de Atacama, Chile; Paula Pacheco; Centro de Apoyo a la Gestión Sustentable del Agua y el Medio Ambiente “Agua Sustentable”, La Paz, Bolivia
The floristic composition and distribution of plant communities is the product of species-specific responses to localized environmental conditions often structured following environmental gradients. Although the importance of Andean high-elevation wetlands (bofedales) for provisioning ecosystem services has been critically emphasized in various studies, very little is known about how different micro-environmental factors shape their zonation and community assembly. Here we examined and quantified differences in herbaceous plant composition, alpha diversity, and aboveground biomass within waterlogged and dry habitats in three bofedales located in western Bolivia. Our results show that although alpha diversity was similar between both habitats, obligate wetland taxa were more abundant in waterlogged habitats whereas upland graminoids and halophytes were predominant in desiccated habitats. Furthermore, aboveground biomass of obligate wetland graminoids was higher in waterlogged habitats, while saline tolerant forbs exhibited higher aboveground biomass in desiccated habitats. Together these results suggest that soil water and organic matter content largely governs plant composition and biomass production but not alpha diversity in the studied high-altitude Andean wetlands. These results have important consequences for predicting plant species’ response to changes in the hydrological cycle due to habitat degradation and aridification caused by land use intensification and global climate change.
Pollen limitation and reproductive incompatibility system in a critically endangered tree, Polylepis incarum (Bitter) M. Kessler & Schmidt-Leb (Rosaceae)
(Taylor & Francis, 2021) Cecilia L. López; Alejandra I. Domic; César Mayta; Emilia García; Jorge A. N. Quezada; Silvia C. Gallegos
Anemophilous species depend on wind for sexual reproduction. When plants do not receive enough pollen and/or pollen has poor quality, they may experience pollen limitation. This can reduce the production of fruits and seeds with negative consequences on population dynamics. The self-compatibility system also plays an important role on the likelihood of a species suffering pollen limitation as it determines if plants can produce fruits and seeds in the absence of compatible mates. Here, we studied the breeding system of the Andean anemophilous tree Polylepis incarum, a critically endangered species endemic to Lake Titicaca. We conducted controlled experimental pollination experiments and florescence microscopy analysis to assess whether pollen limitation and the incompatibility system constrain fruit and seed production. Results showed that the seed set is limited by pollen availability, that P. incarum exhibits a pre-zygotic compatibility system and early inbreeding depression manifested during seed development. Therefore, self-pollination is a factor that could be partially associated with the production of non-viable seeds.
Pollination Ecology ofPolylepis tomentella(Rosaceae), an Andean Anemophilous Tree Presenting a Potential Floral Fungal Infection
(University of Chicago Press, 2017) Alejandra I. Domic; Peter Bernhardt; Retha Edens-Meier; Gerardo R. Camilo; José M. Capriles
Premise of research. Anemophily is considered to be a mechanism that evolved to promote pollination success. However, reproductive output can decrease if pollen loads are scarce due to low abundance of compatible mates or floral infections. Here we analyze the effects of breeding system, pollen limitation, and a potential floral fungal infection on the reproductive output of the Andean tree Polylepis tomentella (Rosaceae).Methodology. We performed pollen supplementation experiments in the field to assess the extent of the effect of pollen limitation on fruit and seed set and to identify any pre- or postzygotic self-incompatibility responses within receptive pistils. Supplementary scanning electron microscopy and epifluorescence microscopy were used to observe the possible effects of a potential floral fungal infection on sexual reproduction.Pivotal results. Pollen supplementation did not increase fruit and seed set, suggesting weak evidence of pollen limitation. Most stigmas from self- and cross-pollinated flowers showed germinated pollen grains and pollen tubes in the style, indicating that the species exhibits prezygotic self-compatibility. The presence of three Ascomycota genera in stigmas and styles appears to have negatively affected the germination of pollen grains by inhibiting pollen tube growth, but we did not find evidence suggesting that hyphae are able to penetrate the ovary.Conclusions. This study showed that P. tomentella possesses a prezygotic self-compatible system and that fruit and seed set are not affected by pollen limitation. Therefore, reproductive assurance is achieved through pollen transfer between plants by wind and the role played by self-compatibility that allows selfing in the species. However, it is possible that the potential fungal infection could reduce the fecundity of its tree host, as hyphae are able to penetrate pollen grains.
Polylepis incarum (Rosaceae) una especie En Peligro Crítico en Bolivia: Propuesta de reclasificación en base al área de ocupación y estructura poblacional
(2017) Alejandra I. Domic; Arely N. Palabral-Aguilera; María Isabel Vargas; Rosember Hurtado; Noel Ortuño; Máximo Liberman
Small‐scale Farming and Grazing Reduce Regeneration of Polylepis tomentella (Rosaceae) in the Semiarid Andes of Bolivia
(Wiley, 2013) Alejandra I. Domic; Gerardo R. Camilo; José M. Capriles
Abstract In the Andean highlands, Polylepis woodlands are a rare and unique ecosystem of the treeline. Although human activities have caused the loss of extensive forested areas and decreased woodland regeneration, few systematic and quantitative assessments have been carried out in Polylepis forests. This study compares differences in habitat characteristics, population structure, and reproductive output in populations of Polylepis tomentella subject to different levels of human disturbance in the south‐central Andes of Bolivia. We selected P. tomentella because the species still covers large extensions in the form of fragmented forest patches. Results show that human activities affected all the studied populations. Moderately disturbed populations exhibited a lower percentage of farmed area (0.6%) and browsed plants (4%) than strongly disturbed populations (5% and 12%, respectively). All populations exhibited similar proportion of plants with logging scars. Potassium content and canopy closure were 1.5 and 2.5 higher, respectively, in strongly disturbed populations. The density of saplings and seedlings were 75 percent and 80 percent lower in strongly disturbed populations than in moderately disturbed population, even though reproductive individuals produced twice more flowers and fruits. Our results suggest that fruit production does not limit regeneration of P. tomentella and post‐dispersal mechanisms may decrease seed germination and increase seedling mortality. Overall, strongly disturbed populations will be less likely to regenerate, leading to population decline. Conservation programs should facilitate forest recovery by promoting seedling establishment, reducing overharvesting and over‐browsing, and protecting remaining adult plants.
Two Thousand Years of Land-Use and Vegetation Evolution in the Andean Highlands of Northern Chile Inferred from Pollen and Charcoal Analyses
(Multidisciplinary Digital Publishing Institute, 2018) Alejandra I. Domic; José M. Capriles; Katerine Escobar‐Torrez; Calógero M. Santoro; Antonio Maldonado
The European conquest of the New World produced major socio-environmental reorganization in the Americas, but for many specific regions and ecosystems, we still do not understand how these changes occurred within a broader temporal framework. In this paper, we reconstruct the long-term environmental and vegetation changes experienced by high-altitude wetlands of the southcentral Andes over the last two millennia. Pollen and charcoal analyses of a 5.5-m-long core recovered from the semi-arid puna of northern Chile indicate that while climatic drivers influenced vegetation turnaround, human land use and management strategies significantly affected long-term changes. Our results indicate that the puna vegetation mostly dominated by grasslands and some peatland taxa stabilized during the late Holocene, xerophytic shrubs expanded during extremely dry events, and peatland vegetation persisted in relation to landscape-scale management strategies by Andean pastoralist societies. Environmental changes produced during the post-conquest period included the introduction of exotic taxa, such as clovers, associated with the translocation of exotic herding animals (sheep, cattle, and donkeys) and a deterioration in the management of highland wetlands.
Wetlands of Mountain Regions of Bolivia
(2025) Alejandra I. Domic; Óscar Plata; Rosana Moraes
Andean mountain wetlands are ecosystems found in the semiarid and arid Bolivian Andes between 3500 and 5000 m a.s.l. They are characterized by the presence of unique and distinctive plant communities adapted to extreme environmental conditions, including large daily temperature variations, night frosting, and exposure to high levels of UV light. Indigenous communities rely heavily on mountain wetlands, and they have developed a suite of strategies to maintain and expand peatlands over generations. Despite major efforts to document the flora and fauna associated with these ecosystems during the past decades, global warming and land-use intensification constitute major threats to the stability of these ecosystems. Conservation programs should include the active participation of local indigenous communities to develop new strategies for conservation planning in the light of climate change.