Serviço ecossistêmico do solo de estoque de carbono e plano de segurança da água

Abstract

The soil system is an important carbon storage compartment, with this ecosystem service playing a key role in the balance of greenhouse gases. Another ecosystem service (SES) that we depend on are those related to the water cycle, such as provisioning, regulation, support and cultural services. These SES must be evaluated when preparing Water Safety Plans (PSA) in systems with collection from groundwater wells or surface reservoirs. Soil analysis provides us with data on the regulation and retention of water in the environment, essential to complement the PSAs methodology, which aims to analyze the risks and dangers on supply sources that threaten the quality and quantity of this natural resource for the population.Knowledge of soil classes, soil cover/use and management and the quantification of the C stock in the cities of Alagoinha, Curral de Cima, Itapororoca and Riachão do Poço in the state of Paraíba strengthened the PES methodology, because with the quantitative and qualitative assessment it was possible to understand that good environmental preservation practices influence the carbon stock in the soil, this stock being an environmental conditioner that promotes the retention and regulation of water in the systems by improving the physical, chemical and biological attributes of the soil. In the cities studied, between 3 (three) and 7 (seven) profiles were opened where samples were collected by pedogenetic profile and fixed layers of 10cm, for morphological, physical and chemical characterization with an emphasis on carbon stock. The profiles corresponding to the town of Alagoinha showed a carbon stock - CE ranging from 36 to 403 Mg ha-1 in the pedogenetic horizons and from 0.5 to 6 Mg ha-1 in the fixed layers, the CE of Curral de Cima ranged from 2 to 61 Mg ha-1 in the horizons and from 0, 5 to 15 Mg ha-1 in the fixed layers, the CE of Itapororoca ranged from 8.9 to 96 Mg ha-1 in the horizons and from 4.4 to 15 Mg ha-1 in the fixed layers and the CE of Riachão do Poço ranged from 9.5 to 178 Mg ha-1 in the horizons and from 0.7 to 19 Mg ha-1 in the fixed layers. Based on these values, the cities studied showed potential for environmental and economic valuation, and projects for the acquisition of carbon credits could be implemented in these municipalities. The importance of evaluating soils in terms of the ecosystem service of carbon stock is understood, as this service conditions the environment and maintains life, since soil is the main ecological stratifier and source of the main ecosystem services.