Effects of human activities on hydrophysical and chemical soil properties in montane forest and páramo ecosystems in the Ecuadorian Andes
Thursday, 9 June 2016
Pablo Quichimbo1,2, Franklin Marín3, Carlos Quiroz3,4 and Patricio Crespo1, (1)Universidad de Cuenca, Departamento de Recursos Hídricos y Ciencias Ambientales & Facultad de Ciencias Agropecuarias, Cuenca, Ecuador, (2)Dresden University of Technology, Dresden, Germany, (3)Universidad de Cuenca, Departamento de Recursos Hídricos y Ciencias Ambientales, Cuenca, Ecuador, (4)Technische Universität München, München, Germany
Abstract:
In Ecuador, montane forest and páramo ecosystems in the Andean region are essential from an environmental and socio-economic perspective; due to they provide a number of environmental services including the hydrological services. These services are largely provided by the particular properties of their soils. However, the soils have been affected by several human activities such as the establishment of pastures, crops, and afforestation or reforestation practices. In this context, several works have been developed to study the effect of such activities. However, they have been carried out in an isolated way, either focusing only in páramo or in montane forest areas. Therefore, there are no generalizations about effects on a larger scale encompassing these two mountain ecosystems. This study aimed to assess the effects of the main human activities on the physical and chemical soil properties in areas of montane forest and páramo in the south-central Andean region of Ecuador. The following soil properties were studied: hydraulic conductivity, bulk density, texture, soil moisture content (at saturation point, field capacity and wilting point), pH, soil organic matter, base saturation, cation exchange capacity and soil nutrient content; these properties were analyzed according to the following land uses: annual crops, pastures, tussock grasslands under grazing, burned tussock grasslands and pine plantations against undisturbed soils from both ecosystems (páramo and montane forest). The results of this study show that impacts on soils were different for the two ecosystems. Thus, in montane forests, annual crops caused changes in a greater number of hydrophysical properties, significantly affecting the hydraulic conductivity, bulk density and soil moisture content. By contrast, in páramo zones, pine plantations were the cause of the biggest changes on soils, affecting both hydrophysical and chemical soil properties. Overall, human activities caused a greater impact on hydrophysical properties in the study area, having a direct effect on the movement, storage and regulation of water, aspects that should be considered for planning land use in the region.
