Spatial patterns of vacant lots and green infrastructure in urban landscapes

Studies of the spatial patterns of the green infrastructure of vacant lots and vulnerable areas in cities are fundamental to support actions aimed at urban sustainability. The present thesis had as main objectives to characterize the urban landscape of Belo Horizonte, located in southeastern Brazil, with regard to aspects of the particular composition of the land cover patterns of vacant lots; the configuration or patterns of the vacant lot arrangements and functional connectivity in vulnerable green areas of the city provided by a bird species effective in dispersing seeds of tropical plants. To achieve the objectives, combinations of ecological data, socioeconomic information, mapping, statistical analysis, spatial analysis and modeling of ecological processes were used. The results for the composition of vacant lots in the city showed a diversified land cover and the predominance of lots composed of herbaceous-shrubby vegetation. In addition, there was an expressive representation of lots consisting of trees clumps and native vegetation, capable of benefiting the city and its population, through the provision of ecological functions and potential ecosystem services for regulation and support. Regarding the landscape configuration, it was evidenced that the patterns of the vacant lot arrangements are defined mainly by the metrics related to the area and distance between lots. These metrics, in turn, responded mainly to socioeconomic factors, population density and number of protected areas within the 1500 meters perimeter around the lot. Lots of different land cover were found closer together and connected to protected areas, which reinforces structural connectivity, which can benefit elements of urban fauna and flora. In addition, high vegetation quality lots tended to be distributed over closer distances, but in neighborhoods with a low number of protected areas, which can emphasize the importance of these lots in terms of expanding the city's preserved green areas. In relation to the routes with the lowest cost or the highest probability of being used by the touco toucan (Ramphastos toco) for movement and dispersion in the northern region of Belo Horizonte, the results showed a low integral connectivity in the studied region; occurrence of few forest patches relevant to connectivity; and areas of importance for functional connectivity under threat of deforestation and disappearance. In general terms, what was evidenced is that the information generated in the study can contribute to urban planning on a sustainable basis. The temporary occurrence of vacant lots with their varied types of vegetation and land cover, as well as their particular configuration, positively impacts the environmental quality of the city. On the other hand, the regulation of land use has not contained excessive use and exposure of used lots to total impermeability, contrary to the legislation that provides for permeability ratios of 10% to 20%. There is also a need to reassess the planning for vulnerable green areas in the northern region, including aspects of conservation of ecological connectivity and consequently biodiversity.