Carbon emissions in Pantanal Lagoons (Brazil) during 2019-2020

This dataset contains limnological variables and methane (CH₄) flux measurements from freshwater and saline–alkaline lagoons in the Brazilian Pantanal collected during 2019 and 2020, a period characterized by an extreme regional drought. The dataset includes measurements of water physicochemical properties (temperature, pH, dissolved oxygen, redox potential, water color, turbidity), concentrations of dissolved carbon and nitrogen (DOCw, TDCw, TDN, and sediment dissolved inorganic carbon), as well as CH₄ fluxes measured across limnetic, littoral, and terrestrial habitats. The data capture pronounced interannual changes driven by drought conditions, including substantial increases in DOCw, TDCw and TDN in both lagoon types, reflecting solute concentration linked to reduced water volume. Additional responses were lagoon-type specific: freshwater lagoons showed higher temperature, pH, dissolved oxygen, and redox potential, whereas saline–alkaline lagoons exhibited increased water color and sediment inorganic carbon. Methane fluxes documented in this dataset highlight strong sensitivity to hydrological stress. During the 2020 drought, freshwater lagoons showed increased CH₄ emissions from both limnetic and terrestrial habitats, while saline–alkaline lagoons displayed higher emissions mainly in littoral and terrestrial zones. Correlation analyses included in the dataset indicate that CH₄ fluxes are strongly associated with DOC, TDC, and TDN in the water column, with additional controls such as oxygen and redox conditions in freshwater lagoons and turbidity and nitrogen availability in saline–alkaline systems. This dataset enables investigations into how extreme climatic events modulate limnological properties, biogeochemical cycles, and greenhouse gas dynamics in tropical wetland ecosystems. It is suitable for comparative studies, ecological modeling, carbon budget assessments, climate-impact analyses, and applications supporting conservation and management of the Pantanal.