Claudia P. Romero

This research analyzes the impact on land use induced by urban solid waste landfills using the Weighted Environmental Index (WEI). The methodology used to analyze the environmental value of the landfill’s areas of influence is based on the analysis of the space-time variations of the WEI inside them. The application of this methodology allows identifying the areas where the environmental value has changed over time, providing a quantitative indicator that can be analyzed using statistical techniques. The methodology has been applied as a case study to analyze the influence over land use in all the municipal solid waste landfills currently in operation inside the Valencia Region (Spain). Results have been obtained using GIS techniques integrating the information provided by the Information System on Land Occupation in Spain land use database. Results show that, without exception, the environmental value of the territory has decreased in all the cases analyzed. WEI is a powerful tool for analyzing land use change over time, and its application allows for performing detailed statistical analyses leading to key conclusions about land use changes inside the landfill influence areas.

Usually, megacities expand without proper planning in a context of demographic growth and are increasingly dependent on the natural resources related to the occupied area. This is a major challenge for the sustainable management of these territories, justifying the need for a better knowledge of land use/land cover (LULC) distribution and characteristics to observe spatial anthropogenic dynamics. In this study, the Bogotá river basin and the Bogotá megacity were analyzed as a case study. The main objective of this work was to analyze the historical LULC dynamics from 1985 to 2014. Reliable forecasting scenarios were developed using the Land Change Modeler to support sustainable management and planning. Results show an expansion of the Bogotá megacity toward the Northeast and an increase of urban areas within the basin. These changes implied a loss of 58% of forest surface, a strategic ecosystem, from 1985 to 2014. This dynamic is expected to continue, with a 50% increase of urban areas between 2012 to 2050, thus the megacity and neighbor cities potentially become an “urban continuum”. A replacement of crop and pasture lands near the city is expected, even though Bogotá lands are among the best agricultural lands in the Andean region of Colombia.