KARST IN THE CITY: URBAN SPACE PLANNING OF COZUMEL CITY, MEXICO

Abstract

Background: The growth of the urban slick represents one of the most significant challenges to territorial planning in karst territories. This growth undermines the city's planning systems, generating irregular settlements, disarticulated human settlements, lack of services, coupled with ignorance of ecosystems, a situation that is typical of cities in the northeast of the Yucatan peninsula. The absence of a knowledge system of the physiographic characteristics of the territory has overlooked the karst characteristics of this region, adapting the buildings to a highly complex urban system. Objective: This work aims to develop a model for the recognition of karst depressions and its assessment based on the use of urban land in order to guide karst action policies in the city. Methodology: The study was carried out in the city of Cozumel, Mexico. For this, the cartographic bases were developed in order to recognize the depression units in the city, which were derived from data from seven INEGI LiDAR datasets, with a resolution of 5 m in the horizontal axis, constructing a mosaic dataset that covers the urban stain of the city. Through a management of the original LAS data, an altitude contour map (from 0 to 17 meters) was modeled with an equidistance of 0.25 cm in the vertical axis and with polygons of 25m2 of resolution; subsequently, the positive and negative level contours (depressions) were differentiated. Which were characterized and differentiated by their origin (natural or anthropogenic), type (sinkhole, uvala or polje), depth (from 0.25 to 4.5 m), land use and population density at the city block level. Results: 1,219 depressions were recognized, of which 59% are orbed and orbed to oval sinkholes with less than 1 m depth. Four sectors of the city are distinguished with medium and high housing density, high population density and high density of depressions (between 50 and 90%). Implications: The identification of the units is based on the principles of remote perception and geographic information systems, so that some spatial units will be over-estimated in their number or underestimated in their territorial context of the urban area of the city of Cozumel. Conclusions: Most of the sinkholes and uvalas are located in private and business properties (mainly nurseries, ornamental gardens and water vending), government (in the form of theme parks, within land and public parks) and in vacant lots (most are characterized by being open-air dumps) and about 30% is located in the road system. The present analysis model can be implemented in all the northern cities of Quintana Roo under an ecosystem services scheme of these karst units.