Dynamics of changes in land use and estimation of co2 in mangroves in the marismas nacionales area, mexico

Abstract

In recent years, 20% of mangroves have been lost to deforestation worldwide. Mexico is one of the countries with the greatest loss in mangrove surface area, contributing to CO2 emissions and promoting climate change. However, knowledge about the factors that influence the loss and gain in mangroves, CO2 emissions, and the dynamics of land use and vegetation cover at local and regional scales is lacking. There-fore, the objectives of this study were to analyze land use dynamics in the Marismas Nacionales area (Mexico) from 1981 to 2015, to determine the rate of mangrove deforestation and annual degradation, and to estimate the CO2 emissions derived from these processes using geographic information system techniques. To determine land use changes, we used the cross-tabulation matrix and obtained various change parameters that allowed generating an equation to estimate the rates of deforestation and degradation. We used data from the National Inventory of Emissions of Greenhouse Gases and Compounds (Mexico) to estimate CO2 emissions and absorptions (equivalent, CO2e) prompted by mangrove deforestation, degradation, reforestation, and natural recovery. For the 1981–2005 period, the emissions estimate was 432.50 Gg of CO2e due to the annual mangrove deforestation rate of 0.77%, and degradation was 27.16 Gg of CO2e, with an annual rate of 7.64%. For the 2005–2015 period, the emissions estimate was 145.21 Gg of CO2e due to an annual deforestation rate of 0.44%, and degradation was 24.80 Gg of CO2e, with an annual rate of 4.94%. The greatest mangrove loss was due to transformation into land in the agricultural-livestock and anthropic development categories. Degradation was due to natural phenomena and anthropogenic activities.