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Introduction. Efforts have been made in Colombia to increase the use of certified seed. However, the lack of knowledge among producers about its advantages, the absence of a stable supply and the dependence on commercial potato prices, limit the sustainability of its production. Objective. To evaluate financially and biophysically the production of seed potatoes in the department of Nariño, Colombia. Materials and methods. The use, evolution, adoption, and costs of potato seed were evaluated between May 2016 and April 2018, to consolidate bases that allow creating sustainable production models. This information was collected through surveys to 1018 producing households in twenty-one local municipalities. To define the biophysical parameters, a semi-structured interview was used to extract ranges and aptitudes in cartographic layers, which were framed in an area with rainfall between 800 to 1600 mm year-1, loamy soils with slopes of 15 %, altitude between 2800 to 3200 m.a.s.l. and temperature of 8 to 15 ° C. The agribusiness behavior was established with a seven-year projection of production costs, based on a review of primary sources and figures of areas sown during the last ten semesters, which was compared with the estimate of the percentage of current seed use in the region to establish the potential demand. Results. The economic burden did not allow generating significant yields in a single hectare (¯X: 6 %), because they were lower than the commercial potato production (¯X: 18 %), with an average of 20 % and internal rate of return (IRR) of 28 %. Conclusion. The minimum area to overcome the profitability of commercial potato production was three hectares, managing to supply 3 % of the seed demand. The areas with greatest potential for production were the municipalities of Pasto, Tangua, and Sapuyes., Introducción. En Colombia se han realizado esfuerzos por masificar el uso de semilla certificada, sin embargo, el desconocimiento de los productores en sus ventajas, la inexistencia de una oferta estable y la dependencia al precio de papa comercial, limitan la sostenibilidad de su producción. Objetivo. Evaluar financiera y biofísicamente la producción de semilla de papa en el departamento de Nariño, (Colombia). Materiales y Métodos. Se evaluó el uso, evolución, adopción y costos de semilla, entre mayo de 2016 y abril de 2018, para consolidar bases que permitan crear modelos de producción sostenibles. Dicha información fue recopilada por encuestas a 1018 hogares productores en veintiún municipios de la localidad. Para definir los parámetros biofísicos se utilizó una entrevista semiestructurada para extraer rangos y aptitudes en capas cartográficas, que se enmarcaron en un área con precipitación entre 800 a 1600 mm año-1, suelos francos con pendientes del 15 %, altitud entre 2800 a 3200 msnm y temperatura de 8 a 15 °C. El comportamiento del agronegocio se estableció con proyección de costos de producción a siete años, a partir de revisión de fuentes primarias y cifras de áreas sembradas durante los últimos diez semestres, que fue cotejada con la estimación del porcentaje de uso actual de semilla en la región para establecer la demanda potencial. Resultados. La carga económica no permitió generar rendimientos significativos en una sola hectárea (¯X: 6 %), porque fueron inferiores al de la producción de papa comercial (¯X: 18 %), con un promedio 20 % y una tasa interna de retorno (TIR) del 28 %. Conclusión. El área mínima para superar la rentabilidad de la producción de papa comercial fue de tres hectáreas, logrando suministrar el 3 % de la demanda de semilla. Las zonas con mayor potencial para producción fueron los Municipios de Pasto, Tangua y Sapuyes.

Land-use change and intensification threaten bee populations worldwide, imperilling pollination services. Global models are needed to better characterise, project, and mitigate bees' responses to these human impacts. The available data are, however, geographically and taxonomically unrepresentative; most data are from North America and Western Europe, overrepresenting bumblebees and raising concerns that model results may not be generalizable to other regions and taxa. To assess whether the geographic and taxonomic biases of data could undermine effectiveness of models for conservation policy, we have collated from the published literature a global dataset of bee diversity at sites facing land-use change and intensification, and assess whether bee responses to these pressures vary across 11 regions (Western, Northern, Eastern and Southern Europe; North, Central and South America; Australia and New Zealand; South East Asia; Middle and Southern Africa) and between bumblebees and other bees. Our analyses highlight strong regionally-based responses of total abundance, species richness and Simpson's diversity to land use, caused by variation in the sensitivity of species and potentially in the nature of threats. These results suggest that global extrapolation of models based on geographically and taxonomically restricted data may underestimate the true uncertainty, increasing the risk of ecological surprises.