Land Use/Land Cover (LU/LC) Changes and its impact on Soil Organic Carbon Stock in Killiar River Basin, Kerala, India: A Geospatial Approach

Sabu Joseph,Sukanya S,Rahul R

doi:10.12944/cwe.16.3.2

Abstract

The changes in the pattern of land use and land cover (LU/LC) have remarkable consequences on ecosystem functioning and natural resources dynamics. The present study analyzes the spatial pattern of LU/LC change detection along the Killiar River Basin (KRB), a major tributary of Karamana river in Thiruvananthapuram district, Kerala (India), over a period of 64 years (1957-2021) through Remote Sensing and GIS approach. The rationale of the study is to identify and classify LU/LC changes in KRB using the Survey of India (SOI) toposheet (1:50,000) of 1957, LISS-III imagery of 2005, Landsat 8 OLI & TIRS imagery of 2021 and further to scrutinize the impact of LU/LC conversion on Soil Organic Carbon stock in the study area. Five major LU/LC classes, viz., agriculture land, built-up, forest, wasteland and water bodies were characterized from available data. Within the study period, built-up area and wastelands showed a substantial increase of 51.51% and 15.67% respectively. Thus, the general trend followed is the increase in built-up and wastelands area which results in the decrease of all other LU/LC classes. Based on IPCC guidelines, total soil organic carbon (SOC) stock of different land-use types was estimated and was 1292.72 Mt C in 1957, 562.65 Mt C in 2005 and it reduced to 152.86 Mt C in 2021. This decrease is mainly due to various anthropogenic activities, mainly built-up activities. This conversion for built-up is at par with the rising population, and over-exploitation of natural and agricultural resources is increasing every year.

Highlights

Land use/land cover (LU/LC) change has been identified as one of the most potent anthropogenically driven repercussions on environment
The results of land use and land cover (LU/LC) change detection based on comparative change analysis are given in Table 1, 2 and 3
Various categories of LU/LC were delineated from the study area including agricultural land, built-up land, forest, water bodies and waste lands

Summary

Introduction

Land use/land cover (LU/LC) change has been identified as one of the most potent anthropogenically driven repercussions on environment. The latter half of the 20th century witnessed land use changes emerging as a widespread phenomenon all over the world.[1] Monitoring LU/LC changes is one of the most important components to evolve strategies for managing natural resources and monitoring environmental changes.[2,3,4] Urban development. Information on LU/LC changes helps to understand changes of environment and assist decisionmakers to plan suitable projects for sustainable development.[8,9] Landsat data provides longest record with large-scale medium spatial resolution earth observation data.[10,6,11] Urban expansion settings in many parts of the world pose a vital impact on a wide range of sectors viz., ecology, climate, hydrological systems, land use, energy flow etc., all of which can be tracked through LU/LC change detection analysis.[12,13,14]

Methods

Results

Conclusion