La pandemia del COVID-19 trajo consigo una serie de desafíos para el sector agrícola. Pequeños, medianos y grandes agricultores se han visto afectados debido a que las medidas de seguridad tomadas ...impactaron negativamente las ventas de sus productos, ocasionando pérdidas. Debido a esto, surgió la necesidad de acoger las plataformas digitales como nueva forma para comercializar sus productos. Esto ha sido un desafío, ya que el acceso a las Tecnologías de la Información y Comunicación (TIC) es limitado para estos sectores. Este artículo presenta el desarrollo del proyecto AgroTIC, el cual surgió para afrontar las necesidades mencionadas, y se ejecutó aplicando metodologías ágiles y Scrum. En él se plantean estrategias para incorporar acciones que faciliten y promuevan el uso de plataformas de comercio electrónico, eliminando intermediarios y garantizando que las transacciones se realicen directamente con los productores. De esta manera, se busca mejorar el sostenimiento socioeconómico de los agricultores del departamento de Nariño, ubicado en el sur de Colombia. Uno de los resultados obtenidos al transcurrir once meses de ejecución del proyecto es el desarrollo de la página web AgroTIC, en la cual se han registrado un total de 2.645 usuarios interactuando activamente y 325 usuarios registrados. La plataforma ha facilitado un total de 718 ventas, generando un volumen por un valor aproximado de 88.942.683 pesos colombianos. Estos resultados subrayan el impacto positivo de AgroTIC, facilitando transacciones y proporcionando una plataforma eficiente para conectar a agricultores con consumidores.
Understanding and predicting the likely response of ecosystems to climate change are crucial challenges for ecology and for conservation biology. Nowhere is this challenge greater than in the tropics ...as these forests store more than half the total atmospheric carbon stock in their biomass. Biomass is determined by the balance between biomass inputs (i.e., growth) and outputs (mortality). We can expect therefore that conditions that favor high growth rates, such as abundant water supply, warmth, and nutrient-rich soils will tend to correlate with high biomass stocks. Our main objective is to describe the patterns of above ground biomass (AGB) stocks across major tropical forests across climatic gradients in Northwestern South America. We gathered data from 200 plots across the region, at elevations ranging between 0 to 3400 m. We estimated AGB based on allometric equations and values for stem density, basal area, and wood density weighted by basal area at the plot-level. We used two groups of climatic variables, namely mean annual temperature and actual evapotranspiration as surrogates of environmental energy, and annual precipitation, precipitation seasonality, and water availability as surrogates of water availability. We found that AGB is more closely related to water availability variables than to energy variables. In northwest South America, water availability influences carbon stocks principally by determining stand structure, i.e. basal area. When water deficits increase in tropical forests we can expect negative impact on biomass and hence carbon storage.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The Peruvian scallop (Argopecten purpuratus, Lamarck 1989) is a marine bivalve of high commercial value in the aquaculture industry, with wild populations distributing from northern Peru to Chile. ...Growing demand for it in the world aquaculture markets and limited availability of hatchery‐based seeds caused long‐term seed translocations among wild populations to recover depleted local populations and for production needs. We investigated long‐term translocation effects on the genetic diversity and structure of wild populations using next‐generation RAD sequencing. We sampled individuals from Sechura, Lobos de Tierra, Samanco, and Bahia Independencia in Peru, and La Rinconada in Northern Chile. We identified 8,345 polymorphic RAD loci and 24,218 SNPs for the five populations. We estimated high observed heterozygosity for all populations and high SNP frequency compared to similar studies on marine bivalves. We detected no spatial divergence among populations in Peru (pairwise FST from 0 to 0.003), but strong differentiation with the population in Chile. Migration rate estimates suggested asymmetric directionality of seed translocation. Overall, our results support a remnant effect of an intense historic translocation and ongoing gene flow among wild populations in Peru, challenging the identification of outlier loci and certification of sustainable origin of cultured scallops using genetic markers.
General patterns of forest dynamics and productivity in the Andes Mountains are poorly characterized. Here we present the first large-scale study of Andean forest dynamics using a set of 63 permanent ...forest plots assembled over the past two decades. In the North-Central Andes tree turnover (mortality and recruitment) and tree growth declined with increasing elevation and decreasing temperature. In addition, basal area increased in Lower Montane Moist Forests but did not change in Higher Montane Humid Forests. However, at higher elevations the lack of net basal area change and excess of mortality over recruitment suggests negative environmental impacts. In North-Western Argentina, forest dynamics appear to be influenced by land use history in addition to environmental variation. Taken together, our results indicate that combinations of abiotic and biotic factors that vary across elevation gradients are important determinants of tree turnover and productivity in the Andes. More extensive and longer-term monitoring and analyses of forest dynamics in permanent plots will be necessary to understand how demographic processes and woody biomass are responding to changing environmental conditions along elevation gradients through this century.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The acid mine drainage (AMD) can causes negative impacts to the environment. Physico-chemical methods to treat AMD can have high operational costs. Through passive biological methods, such as ...anaerobic reactors, sulfate reduction, and recovery of metals are promoted. This study evaluated the performance of a horizontal anaerobic immobilized biomass (HAIB) reactor for the treatment of synthetic AMD using polyurethane foam as support material, and anaerobic sludge as inoculum. Ethanol was used as an electron donor for sulfate reduction, resulting in an influent chemical oxygen demand (COD) in the range of 500-1,500 mg/L and COD/sulfate ratio at 1. A gradual increase of sulfate and COD concentration was applied that resulted in COD removal efficiencies higher than 78%, and sulfate removal efficiencies of 80%. Higher sulfate and COD concentrations associated with higher hydraulic retention times (36 h) proved to be a better strategy for sulfate removal. The HAIB reactor was able to accommodate an increase in the SLR up to 2.25 g SO
4
2−
/L d
−1
which achieved the greatest performance on the entire process. Moreover, the reactor proved a suitable alternative for reaching high levels of metal removal (86.95 for Zn, 98.79% for Fe, and 99.59% for Cu).
Global climate crisis and severe water scarcity worldwide demand alternative genotypes that allow an adequate balance between production and water use while ensuring benefits for foresters. The ...genetic improvement of water use efficiency (WUE) in forest plantations could reduce water use without compromising yield. Above-ground biomass (AGB), saw-wood volume up to small-end diameter of 15 cm (V15), wood density (WD) and intrinsic WUE (WUE
i
) from wood carbon isotopic discrimination was evaluated in forty open-pollinated families of
G. arborea
grown in a tropical dry forest known as a water-limited environment, to select superior genotypes considering a balance in wood production and water use. Heritability of open-pollinated family means were moderate with values of h
2
f
= 0.554 for AGB, h
2
f
= 0.541 for V15, h
2
f
= 0.608 for WD and h
2
f
= 0.495 for WUE
i
. Significant genetic correlations between both WD and WUE
i
and production traits (p < 0.05) and a nonsignificant genetic correlation between WD and WUE
i
were found. Although production traits and WUE
i
showed moderate narrow-sense and family means heritabilities, considerable responses to selection of up to 13.7% in AGB, 15.5% in V15, 2.5% in WD and 3.0% in WUE
i
could be achieved from intensive selection of superior families. Our results showed that it may be possible balancing wood production and WUE by selecting open-pollinated families of
G. arborea
with higher V15 and WUE
i
. The deployment of these superior families can be used as a forest management strategy to adapt the species to future drought scenarios associated with global climate change.
The Vaupés River stands out as one of the few within the Amazon basin due to its numerous rapids. These riverine fast-flowing sections not only provide habitat to highly specialized fishes but also ...function as natural barriers hindering the movement of fish along its course. During a fish-collecting expedition in the lower Vaupés River basin in Colombia, 95 species were registered belonging to 30 families and seven orders. Despite recent inventories in the region, our comprehensive sampling efforts particularly focused on the rapids and associated rheophilic fauna, allowing us to contribute the first records of four fish species in Colombia (
Myloplus lucienae
Andrade, Ota, Bastos & Jégu, 2016,
Tometes makue
Jégu, Santos & Jégu, 2002, also first record of the genus,
Leptodoras praelongus
(Myers & Weitzman, 1956), and
Eigenmannia matintapereira
Peixoto, Dutra & Wosiacki, 2015) and six presumably undescribed species (i.e.,
Jupiaba
sp.,
Moenkhausia
sp.,
Phenacogaster
sp.,
Bunocephalus
sp.,
Hemiancistrus
sp., and
Archolaemus
sp.). In this study, a commented list of the ichthyofauna of these environments is presented, as well as a photographic catalog of fish species integrated into the CaVFish Project – Colombia.
Los bosques secos tropicales son ecosistemas complejos y frágiles con alta intervención antrópica y ciclos reproductivos restringidos. Albergan riqueza, diversidad estructural, fisiológica y ...fenológica únicas. Esta investigación se desarrolló en el valle del Alto Magdalena, en cuatro fragmentos de bosque con diferentes estados sucesionales. En cada fragmento se establecieron cuatro parcelas permanentes de 0.25 ha y se evaluó el hábitat lumínico asociado a la riqueza, abundancia relativa y rareza de especies, al igual que la dinámica del bosque que contempló mortalidad, reclutamiento y crecimiento diamétrico para un periodo de 5.25 años. En bosque ribereño maduro se encontró una riqueza de especies mayor a la reportada en otros estudios para áreas similares en el Valle del Cauca y la Costa Atlántica. Se evidencian valores de riqueza, heterogeneidad y rareza de especies mayores que los encontrados para zonas más secas del Tolima. La estructura, diversidad y dinámica del bosque se correlacionaron con el hábitat lumínico, mostrando diferencias en la arquitectura del dosel y su papel en la captura y absorción de radiación. Bosques con dosel denso presentan poca disponibilidad de radiación fotosintética activa en el sotobosque, relacionado con baja riqueza de especies, mientras que sotobosques iluminados son más ricos y heterogéneos.
Se evaluó la diversidad florística en doce fragmentos de bosque seco tropical de siete municipios del sur del departamento del Tolima (Colombia), en la Ecorregión Estratégica de la Tatacoa y su área ...de influencia del Alto Magdalena. Se estableció una red de 12 parcelas de 50 x 50 m (0,25 ha), una en cada fragmento, registrándose todos los individuos arbóreos con diámetro superior a 5 cm. Se encontraron 121 morfoespecies agrupadas en 41 familias. La riqueza varió entre 15 y 34 especies por parcela, lo que permitió clasificar las coberturas vegetales en diferentes categorías de diversidad según los índices de riqueza y uniformidad. Se determinó la riqueza estimada, cuyos máximos valores variaron entre 44 y 46 especies. Las parcelas con mayor número de especies únicas alcanzaron valores entre 9 y 11; mientras que los valores mayores de especies únicas con abundancia unitarias estuvieron entre 3 y 5. El modelo de abundancia relativa que mejor describe los bosques evaluados corresponde a la serie logarítmica, sin embargo, cuando corresponden a sucesiones tempranas la serie geométrica mejora considerablemente su ajuste. Los modelos Log-Normal y Broken Stick, tienden a ajustes intermedios. Por otro lado, las relaciones de diversidad beta para estos bosques no superaron el 50% de similaridad. Los resultados permitieron priorizar los bosques en cuanto a su diversidad florística y rareza como potenciales para la futura conservación y restauración del bosque seco tropical del Alto Magdalena.
En este texto se hace una descripción de un fenómeno de transferencia semántico-pragmática a nivel modal del quechua al castellano andino de la región nariñense. El trabajo está organizado de la ...siguiente manera: en primer lugar, se introduce el concepto de evidencialidad; después, se hace una breve descripción histórica del quechua y una introducción a su tipología, y, finalmente, se explica la manera en que el contacto lingüístico quechua-español le dio al castellano andino nariñense los aspectos que lo caracterizan. La metodología usada fue la entrevista etnográfica. Como resultado se obtuvo que la influencia del quechua en el castellano del departamento de Nariño no se dio solamente a nivel léxico o sintáctico, sino que alcanzó niveles más profundos.
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