Análisis de cambio en los usos del suelo: un enfoque a la expansión urbana del cantón Machala, período 1991–2019

Abstract

Changes in land use in recent decades have had repercussions on a global and national level due to the dynamics of anthropic activities, the city of Machala being part of this problem. Under this context, the present study consists of three chapters that consist of: diagnosing the problems of land use changes, then establishing an integrative proposal and finally, an analysis of the feasibility of the proposal through the technical, economic dimensions, social and environmental. Chapter I, diagnosis of the object of study, aimed to analyze the changes in land use in the urban area of ​​the city of Machala between the period 1991-2019, for this cartographic information was collected from the IGM and USGS, through the cartographic processing in ArcGis identified the four categories of land use (agricultural, urban, shrimp and forest). As a result, it was obtained that in 1991, the predominant land use was Agricultural with 63.84%, in second place, urban use with 31.23%, as for the year 2019, there was a dominance of urban use with 53.12% on 41.68% of agricultural soils. Chapter II is developed based on an integrating proposal whose objective is the development of a prospective model for the year 2040 in the urban area of ​​Machala. The simulation of predictive scenarios of Markov Chains was applied in IDRISI-SELVA, with the results obtained a cross-tabulation was made between the period 2019-2040 where 12 transitions of land use change were shown, the coverage with the greatest dominance of changes is the agricultural and urban, coinciding with what was stated in chapter I. The third chapter analyzes the feasibility of the dimensions: technical, economic, social and environmental. The technical dimension was developed through a diagram of the technical process of collecting and processing information until obtaining the maps of land use change and prospecting for the next 21 years, the economic dimension is based on the model of avoided or induced costs, in which it is demonstrated that the application of cartography can avoid future expenses to municipalities and autonomous governments for an effective territorial ordering; The social dimension is developed according to a SWOT matrix, while to understand the feasibility of the environmental dimension, a matrix of the PER Model (Pressure-State-Response) has been developed where the environmental pressures that are occurring in Machala are visible. the current state, impacts and responses to mitigate them. In conclusion, the changes in land use in the period 1991-2019 were related to the reduction of 1587.35 hectares of agricultural land, and an increase of 1616.53 hectares of urban land, in addition the surface of the territory presented 29.38% of changes, while which remained at 70.61%. The predictive model carried out in the IDRISI SELVA software showed that the area of ​​agricultural use will be reduced by the continuous expansion of urban coverage, presenting a significant change of 629.16 ha.