Climate Change Impact On Species Distribution Of Styrax Sumatrana In North Sumatra Using Maximum Entropy Modeling Approach

• Main Author: Hadi Saputra (NIM: 25416017), M.
• Format: Theses
• Language: Indonesia
• Subjects: Masalah dan pelayanan sosial lainnya
• Online Access: https://digilib.itb.ac.id/gdl/view/28890
• Institution: Institut Teknologi Bandung

The impact of climate change shown by the ecosystem changing such as in aquatic, land and the forest area. Forest as the larger terrestrial ecosystem senses the impact of climate due to the changes in temperature and precipitation. The changes in climate and land use and land cover affected the suitable area for the tree to distribute in the specific condition. The Styrax sumatrana as one of the tree species that has a higher value in North Sumatra region has threatened by the changes of climate as well as the human activities. This species has established in Styrax garden as the main income for the farmers in North Sumatra. The authority used this species as the potential trees for rehabilitation and reforestation program due to the advantages of the non-timber product. The environment variable and future potential distribution of the species need to address to support the rehabilitation and reforestation program in the future. <br /> <br /> The objectives are to identify the environment variable that contributed to Styrax sumatrana distribution in North Sumatra region and forecast the future potential distribution by considering the climate changes scenario and land use and land cover changes. Four models and two scenarios from CMIP5 implemented in this research followed by the model of land use and land cover (LULC) changes to predict the distribution of Styrax sumatrana in the year of 2050 and 2070. Those four models are CCSM4, CNRM-CM5, MIROC5, and MRI-CGCM3. Two scenario that used are moderate scenario RCP 4.5 and business as usual scenario RCP 8.5. The Maximum Entropy (MaxEnt) model produced present and future potential distribution with 63 presences of Styrax sumatrana as the sample and bioclimatic, biophysical, and anthropogenic as environmental data. Bioclimatic variables consist of 19 climatic unit and presented in the present and future condition. Biophysical variables which are altitude, slope, aspect and soil type used as the input for MaxEnt. Anthropogenic factor represented by LULC divided into 12 categories and predicted using Artificial-Neural-Network based Cellular Automata (ANN-CA) model to generate the future condition. <br /> <br /> The result shows the mean temperature of the coldest quarter give the higher contribution to the model followed by elevation and land use and land cover changes. Styrax sumatrana higher probability to distributed in the altitude above 600 m, with the temperature below 23oC and located in shrub; garden and rice field; forest and plantation; and crop area. The suitable area in the year 2050 reduces to 3.87% and decline to 3.54% in 2070 by 4.5 scenario. The 8.5 scenario shows the suitable area below 3.04% and drops to 1.36% in the year 2050 and 2070 respectively. The changes in land use and land cover shows that the tree distribution in forest and crop classification will reduce while nearest with shrub, garden, and rice field increase the probability for Styrax sumatrana to distribute with small changes. <br /> <br /> Based on the results, the authority need to conserve the Styrax garden that was used for the farmer’s community for a decade due to the important of the tree as the main income for the farmers. Moreover, Styrax sumatrana need to be protected by allocated the space for conservation area (mostly in the northern part and highland). Regarding the prediction of LULC changes in the 2050 and 2070, it is important for the authority to reduce the conversion land and deforestation. The reforestation using Styrax sumatrana as the potential trees need to anticipate due to the small probability for the suitable area in the future. <br /> <br /> <br /> Keywords: Climate change, CMIP5, land use land cover, Styrax sumatrana, North Sumatra, SDMs, MaxEnt <br /> <br />