Abstract
Mangrove forests have an important ecological function as absorbing and storing carbon in efforts to mitigate global warming, overcome world climate change due to increased CO2 emissions, and reduce the impact of climate change. Carbon dioxide (CO2) acts as an indicator parameter for water and land activity, related to water-sea interactions and water productivity. The results of data processing show the concentration of CO2 in the Lagoon of the Pekalongan Regency, with the highest average and distribution values at several stations. Total organic carbon ranges between 1.12–13.67% the dissolve inorganic carbon ranges from 27.97 to 99.88 mg/L. CO2 content exceeding 20 mg/L can harm marine life and is an impact of global warming. In addition, sea water temperature varies along the station and is influenced by geographic location, land influence, and sea water mass. Station 3 has the lowest temperature, perhaps due to the influence of offshore sea water masses. This research illustrates the importance of managing mangrove ecosystems, measuring CO2 concentrations in waters, and understanding their impact on the marine environment.