66,754 research outputs found
Bryophyte diversity patterns in flooded and tierra firme forests in the Araracuara Region, Colombian Amazonia
We investigated patterns of bryophyte species richness and composition in two forest types of Colombian Amazonia, non-flooded tierra firme forest and floodplain forest of the Caquetá River. A total of 109 bryophyte species were recorded from 14 0.2 ha plots. Bryophyte life forms and habitats were analyzed, including the canopy and epiphylls. Bryophyte species did not show significant differences between landscapes but mosses and liverworts were different and with opposite responses balancing the overall richness. Independence test showed differences in both life form and habitat use distribution between the two forest types with more fan and mat bryophytes species in the floodplains, and more epiphytic liverworts in the tierra firme forest. Correspondence analysis showed differences in the bryophyte species assemblage between the two forest types where they may be responding to the higher humidity provided by the flooding. Despite of, the environmental differences detected, epiphyll species assemblages were not strongly affected. Apparently, epiphyll habitat is stressful enough to hide the environmental differences between the flooded and Tierra firme forests.Investigamos los patrones de riqueza de especies y composición florística de briofitos en dos tipos de bosque en la Amazonía Colombiana. Bosques no inundados de Tierra firme y bosques periódicamente inundados en los planos inundables del Rió Caquetá. Encontramos 109 especies de briofitos en 14 parcelas de 0.2 ha. Nosotros analizamos diferencias en la distribución de formas de vida y hábitat de los briofitos entre los dos tipos de bosque incluyendo especies del dosel y epifilas. El número de especies de briofitos no mostró diferencias significativas entre los dos tipos de bosque. Pero musgos y hepáticas si tuvieron diferencias con respuestas opuestas balanceando el número total de especies. Pruebas de independencia mostraron diferencias en la distribución de formas de vida y uso de hábitat entre los dos tipos de bosque con más especies de abanicos y esteras en los planos inundables, y más especies de hepáticas epifitas en el bosque de Tierra firme. El análisis de correspondencia mostró diferencias en la composición florística de briofitos entre ambos tipos de bosque, donde las comunidades de briofitos pueden estar respondiendo a un gradiente de humedad aportada por la inundación periódica de los planos inundables. La composición florística de los briofitos epifilos no mostró una separación tan clara entre los tipos de bosque como si fue detectada en los otros hábitat donde los briofitos fueron encontrados. Aparentemente, el hábitat epifilo es suficientemente estresante para ocultar el efecto de las diferentes condiciones ambientales de los bosques inundables y de Tierra firme
Two new Lejeuneaceae records for the Colombian liverwort flora
Two epiphyllous Lejeuneaceae, Cololejeunea surinamensis and Drepanolejeunea polyrhiza, previously known from Amazonian Brazil, are recorded for the first time in Colombia. They were found as epiphylls on understory shrubs in the middle Caquetá area in Colombian Amazonia. Cololejeunea surinamensis was found in the Tierra Firme forests and D. polyrhiza was found in the floodplains of the Caquetá River.Dos especies de Lejeuneaceae epífilas, Cololejeunea surinamensis y Drepanolejeunea polyrhiza, previamente conocidas de los bosques amazónicos de Brasil son reportadas por primera vez para Colombia. Las especies fueron encontradas como epífilas sobre hojas de arbustos del sotobosque en el área del medio Caquetá en la amazonía Colombiana. Cololejeunea surinamensis fue encontrada en los bosques de tierra firme, mientras que D. polyrhiza fue encontrada en los planos inundables del Río Caquetá
Changes in the carbon balance of tropical forest: evidence from long-term plots
The role of the world’s forests as a “sink” for atmospheric carbon dioxide is the subject of active debate. Long-term monitoring of plots in mature humid tropical forests concentrated in South America revealed that biomass gain by tree growth exceeded losses from tree death in 38 out of 50 neotropical sites. These forest plots have accumulated 0.71 + 0.34 tons of carbon per hectare per year in recent decades. The data suggest that neotropical forests may be a significant carbon sink, reducing the rate of increase in atmospheric CO2
Migration and forests in the Peruvian Amazon: a review
This paper reviews the literature on the links between migration and forests in the Peruvian Amazon. It highlights
not only the complexity of the migrant–forest interface in Peru but also the relative lack of research on these
dynamics. Historically, official narratives point to migrants as both the culprits of, and solutions to, the Amazon’s problems. At times, the government has promoted colonization of the Amazon as a means to integrate the region into the country as well as to encourage agricultural expansion and alleviate pressure on limited land in the Andes. In other periods, migrants are blamed for deforestation and environmental degradation in the region. These discourses oversimplify the complexity of the reality facing migrants to the Amazon and the factors that ‘push’ them away from their birthplaces and/or ‘pull’ them to the Amazon. They also treat migrants as a homogenous
group, underestimating: the role of migration within the Amazon, the cyclical nature of migration, processes of
urbanization and multi-site households, and the diversity of livelihoods migrants pursue upon arrival. A more
detailed understanding of migrants, migration and the related conditions and processes driving human mobility
in the Amazon should provide a more effective foundation for defining public policy in the region, for example,
for the identification of strategies to mitigate the impacts of road construction or to support sustainable models of production in areas occupied by smallholder farm families. This review is intended as a step toward a fuller
understanding of these processes by compiling existing information as a point of departure
Diet composition of fish species from the southern continental shelf of Colombia
The diet composition of 30 fish species belonging to 16 families from the Pacific Coast of Colombia is described. Benthic crustaceans (37.5%) and bony fishes (23.7%, chiefly demersal) were the most important food items for the fish species analyzed. Data on diet composition of the fish species are presented for the first time which can be a source of information for trophic modeling
A GEOGRAPHY OF ILLICIT CROPS (COCA LEAF) AND ARMED CONFLICT IN COLOMBIA
Colombia is currently the world´s largest producer of coca leaf and the principal producer of opium poppies in the Americas; the plants are the basic raw materials used to produce cocaine and heroin. This document will analyse the current relationship between these crops and illegal armed groups in Colombia, using the hypothesis that the geographical intensification of the conflict is the principal cause of expanding illicit crop production. This relationship was analysed using a theoretic model, in which an interaction between illegal armed activity and strategic territorial control lead to cocaine production. Spatial analysis techniques were then applied, especially spatial association indicators; and a clear spatial dynamic was observed, related to the two aspects mentioned above. Non parametric exercises were also carried out using matching estimators, to determine the effect illegal armed groups have on coca crops, and also to analyse the efficiency of aerial eradication policies. The results suggest that a large percentage of coca production in Colombia is due to the effects of illegal armed activity. We therefore conclude that the expansion of illegal crop growing is a consequence of the expanding conflict. In contrast, coca crops can only be used to explain a small part of the armed conflict in Colombia. In addition, we found that crop eradication via aerial spraying has not been an efficient tool in the fight against coca production in the country.Illicit crops
La nueva ronda petrolera y el derrumbe del paradigma constitucional
(plurinacionalidad-sumak kawsay-derechos de la naturaleza) con la convocatoria
a una nueva gran ronda petrolera en el centro sur de la Amazonía realizada
en el mes de noviembre de 2012
Reaching the millennium development goal for child mortality : improving equity and efficiency in Ecuador's health budget
health care; infant mortality; health policy;
Misallocation and Productivity in Colombia’s Manufacturing Industries
Following Hsieh and Klenow (2009), this paper studies productivity dispersions in Colombian industrial establishments using the Colombian Annual Manufacturing Survey (AMS) from 1982 to 1998. The United States is used as a benchmark to estimate the reallocation of capital and labor to equalize marginal products across plants in Colombia. Gains are found in manufacturing Total Factor Productivity (TFP) of approximately 3-8 percent and TPF is positively correlated with exporting status, age, size, and location in the central region of the country. There is also suggestive evidence that opening the economy in 1991 is associated with an increase in plant productivity levels for firms that export goods. The 1990 reform that reduced dismissal costs is associated with an increase in productivity, while the reform that increased labor costs in 1993 is associated with a decrease in plants’ productivity. Further work is needed to establish a causal relation between productivity and policy changes.Total Factor Productivity, Industry, Reallocating factors of production, Colombia
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