LULC dynamics and application of nature-based solution in high erosion prone areas of Malappuram District

Abstract

Kerala State is highly vulnerable to natural disasters, mainly soil erosion due to changing climatic dynamics in the steep slope. In 2018 and 2019 flood, some districts in Kerala State were affected by significant floods due to extreme and prolonged rainfall, leads to large and small landslides. Malappuram is one of the districts that got affected in 2018 and 2019 flood. Disaster risks are augmented by a critical factor that has been silently rising in the State now, which is change in the land use pattern and practices. Hence, the Land Use and Land Cover Dynamics study was conducted in the selected watersheds (Kakkarathode – Pulikkal and Palathingal) of Malappuram district, and spotted major landslides in the area. The LULC dynamics were carried out in the different time periods like 2013, 2018 and 2020. LISS IV (5.8 m resolution) satellite images were used for the analysis and field visit, to identify the related changes. Accuracy of the classification was evaluated using error matrices and kappa statistics. The overall accuracies for 2013, 2018 and 2020 were 84.93%, 86.21% and 87.5% respectively and the corresponding Kappa values were 0.82, 0.84 and 0.85 which indicates the high accuracy of the classification. The flood has mainly affected Plantation, Paddy and Mixed Plantation which had been decreased during 2018-20 and has resulted in the emergence of more Barren land and Waste Land. LULC helps in identifying the changes in the erosion prone areas. Moreover, erosion hazardous area and its prioritization in applying the soil management and conservation practices can be effectively done using LULC change assessment. Nature based solutions such as planting trees and grasses (like shrubs, vetiver grass etc.), construction of ponds, creation of green walls and assemblage of vegetations can be adopted in the region of high-risk hazardous area depending on the categorized zone.