In the highlands of southern Colombia and northern Ecuador, soils developed on volcanic ash deposits have specific properties: high water retention, high hydraulic conductivity and high carbon (C) contents. The main role of the soils is to regulate the water available for the dense population living in the valleys. Soil properties and land use depe...
In Mexico, 45 percent of the country suffers from land degradation, 12 percent of which, or some 23 million ha, are degraded due to water erosion. In Michoacán, a state in west-central Mexico, the figure rises to 27 percent. A study of the soil in Michoacán determined that overgrazing was a cause of degradation and a strategy was drawn up to promot...
The objective of this study was to evaluate the relationships between the spectra in the Vis-NIR range and the soil P concentrations obtained from the Pm and Prem extraction methods as well as the effects of these relationships on the construction of models predicting P concentration in Oxisols. Soil samples’ spectra and their Pm and Prem extractio...
A volcanic tuff rock known as cangahua (Ecuador) or tepetate (Mexico) is found throughout the Andes. Problems have arisen as the layers of light but fragile soil that once covered the tuff have been lost for both natural (environmental) reasons and because of over-cultivation. When the soil is gone, the tuff is impermeable and sterile. Now, a proje...
Smallholder farmers in the Taita hills and Mount Kilimanjaro recognize the need to conserve soil nutrients of fields and farms located in the upper, middle and lower zones of mountainous areas. These mountain communities depend on rain-fed subsistence agriculture which means that for sustainable subsistence crop production, they also depend on nutr...
La quinua (Chenopodium quinoa Willd.) muestra una gran variación genética, tanto molecular como morfológica, cuya organización sigue poco conocida. Por medio de ANOVAs y dendrograma caracterizamos la estructura de la variación de marcadores morfofenológicos registrados desde la emergencia hasta la madurez fisiológica en siete poblaciones de quinuas...
