Serviços ecossistêmicos em áreas verdes urbanas no semiárido paraibano

Abstract

The disorderly urbanization process degrades urban green areas, compromising the provision of ecosystem services and the quality of life of the population. In this sense, the maintenance of these green spaces in cities in general, and especially in the semi-arid region, enhances the promotion of various ecosystem services with direct benefits for society. Given this context, the general objective of this thesis was to identify the ecosystem services provided by urban green areas in the city of Patos/PB. Initially, a bibliographical and documentary survey was carried out, followed by the geographic characterization of the study area, which consisted of public squares located in the urban area of the city of Patos/PB. Public squares were selected based on their importance to the city in holding cultural events, density of vegetation cover, health gyms and/or physical structures that promote cultural appreciation and the well-being of the population in general. In total, 06 squares were selected to carry out the research and identify the ecosystem services in loco, they are: Alcides Carneiro, Pedro Guedes, Getúlio Vargas, Edivaldo Motta, José Francisco Filho and Francisco Guedes. Subsequently, the ecosystem provision services were evaluated, based on the identification of plant species contained in the squares and the calculations of biological diversity by Shannon-Weaver and Simpson. Cultural ecosystem services were identified by monitoring (2021) the use of squares for holding cultural events and other related activities. Such ecosystem services were verified in loco and monitored in all public squares studied with adaptations to the restrictions imposed due to the Covid-19 pandemic. However, it is worth mentioning that the climate mitigation ecosystem service was evaluated only in square Getúlio Vargas, due to the availability and safety of the climate sensors used in the research. In this square, temperature and relative humidity data were collected at four points with different characteristics of land use and land cover, using thermo-hygrometers on representative days of the region's dry period. Thematic questionnaires were also applied to the local population regarding the thermal comfort conditions found in the Getúlio Vargas square. In the same way, visitors to all public squares studied were given a perception questionnaire about ecosystem services and the importance of urban green areas in the city of Patos/PB. 41 plant species were identified in all public squares evaluated in the city of Patos/PB, most of them 61,0% (n = 25) of exotic origin. The Getúlio Vargas square had the highest abundance of individuals (n = 151) and the Alcides Carneiro square had the highest ShannonWeaver biological diversity index (1,02). It was found that the sampling point with the least vegetation cover around Getúlio Vargas square had the following TDIs: partially uncomfortable (7,6%), uncomfortable (46,2%) and very uncomfortable (46,2%). The sampling point inside it, which receives the effects of shading from the trees, obtained uncomfortable (92,3%) and partially uncomfortable (7,7%) TDIs. This demonstrates the importance of urban trees in the ecosystem service of climate regulation. With regard to the perception of ecosystem services offered by the squares, the local population cites as main examples the reduction of air temperature (n = 12), socialization (n = 14) and recreation in these environments (n = 12). Public squares in Patos/PB, as urban green areas, have provided different socio-environmental benefits to the city, expressed through all ecosystem services (provision, regulation and cultural) identified in the research. Such data support the importance of conservation and sustainable use of these spaces in urban areas to promote quality of life and well-being.