Impact of Land Use and Land Cover Change on Carbon Storage and Sequestration: The Case of Addis Ababa City and Surrounding Oromia Special Zone .

Abstract

Land use land cover (LULC) change is the key factor that triggers declines in terrestrial carbon stocks all over the world. LULC change particularly in urban areas is becoming the major factor in reducing regional carbon sequestration capacity. While LULC change detection has been the focus of numerous studies in Addis Ababa city and the surrounding Oromia special zone, few efforts have been made on assessing LULC change impacts on carbon storage and sequestration. Therefore, this study aims at analyzing the impact of LULC change on carbon storage and sequestration. The study employed Landsat images from 1990 to 2020 and employed Land Change Modeler (LCM) model to explore the LULC dynamics in the study area to assess where LULC changes are expected to occur in 2050 under businessas-usual (B-a-U) scenario and green scenario. Afterward, the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) model was employed to estimate carbon stored in the study area, analyzing their variations over time (2020?�?2050) under the two scenarios. The results from predicting the B-a-U scenario indicates that a decrease in forest and shrubland, by -29% and -50%, respectively and an increase in built-up, grassland, and cropland by 92%, 17%, and 2%, respectively in 2050. The green scenario indicates an increase in forest land roughly by 19% in 2027. However, the long-term effect of the greenery planning in 2050 reveal that the forest land will decline by -15% between 2027 and 2050.Cosequently, the result observed from modelling carbon storage showed that the total carbon stocks decreasing from 39.1 Tg C in 2020, to 33.6 Tg C in 2050 under the B-a-U scenario. According to the model, if the trend detected in this analysis continues, sequestered carbon it is expected to be 5.5 Tg C in 2050. Correspondingly, observed result depicts sequestered carbon (-2.11 Tg C) by the end of 2050 under the green scenario. The results of the study thus infer that changes in land cover have an effect on carbon stocks, with considerable decline in carbon stocks under the B-a-U scenario in 2050s. Similarly, the green scenario has less impact on the landscape in the long run (2050). If this trend is expected to continue in the coming decades, the consequences will be substantial environmental degradation and decline in carbon storage unless proper measures will be taken. Therefore, a potential policy measures should be taken to mitigate negative effects of LULC change on carbon stocks within the study area.