International Journal of Research and Innovation in Applied Science (IJRIAS) |Volume VIII, Issue II, February 2023|ISSN 2454-6194
Mangala Jayarathne1*, Lal Mervin Dharmasiri2, A.M.C. Dissanayake3
1Senior Lecturer, Department of Geography, University of Kelaniya, Sri Lanka
2Senior Professor and Carder Chair, Department of Geography, University of Kelaniya, Sri Lanka
3Land use planner, Department of Land-use Policy Planning, Sri Lanka
Received: 19 January 2023; Accepted: 03 February 2023; Published: 08 March 2023
Abstracts: Mining is one of the main methods of extracting mineral resources. Due to mining potentially decreasing biodiversity, farmland, soil fertility, and contamination from mining waste may add additional stress on environmental quality and ecosystem services. The research was conducted to identify the loss of land and land-use changes due to clay and sand mining in the left Ma-Oya riverbank of the Katana Divisional Secretariat Division (KDSD). Geographically, environmentally, and socio-economically, the Ma-Oya River basin is one of the unique river basins in Sri Lanka. Due to sand and clay mining, the Ma-Oya River basin’s left and right riverbanks have been highly degraded during the last few decades.
The study used the mixed method to identify the land use and land cover changes, especially the GIS and statistical techniques with quantitative and qualitative data. The study revealed that Ma-Oya left bank with significant modifications and land loss due to critical natural resource exploitation. Mainly clay has been excavated up to 835-meter distance from the left Riverbank of Ma-Oya, covering more than 60 hectares. According to the present value of lands in the area, it was the amount of Rs. 2,728,774,720 (27287 Rs/M). It is noted that there are four or five people lose their life annually due to drowning in these water holes. Moreover, the future prediction of land-use change has become a severe issue. Therefore, it is essential to involvement of government institutes to minimize the risk and establish sustainability.
Keywords: Land Degradation, Spatiotemporal analysis, Clay and Sand Mining, Land use and land cover change
I. Introduction
Sand is a natural aggregate formed by rock erosion over thousands of years (Dan Gavriletea 2017). Soil is an essential source of raw materials such as clay, sand, gravel, and minerals (Madyise 2013). Sand deposits have two origins: terrestrial and marine. Terrestrial sources include residual soil deposits, river channel deposits, and floodplain alluvial deposits, and the most common marine sources are shore and offshore deposits (Dan Gavriletea 2017).¬¬¬
The leading nations mining and processing sand, gravel, and clay are the United States of America, Australia, Austria, Belgium, Brazil, India, Spain, Nigeria, Kenya, and South Africa (Madyise 2013). In Sri Lanka, mining sand deposits in rivers traditionally obtained the sand required for construction (Piyadasa 2011). The increasing use of mechanized extraction in the late 1990s has resulted in heavily localized turbidity, lowering of water tables, bank erosion, land degradation, and salinity intrusion resulting in hardship for agriculture and food security (Piyadasa 2011). In an area with extensive human activity, such as a mining area, several disturbances are likely to significantly change the land use/ land cover (Mi et al. 2019). Existing morphology of river systems, human encroaching, and changes in the floodplains (Chaturani and Jayarathne 2019) directly help for land-use change (Senanayake et al. 2020); also, during transport with heavy vehicles, soil erosion, surface water, and groundwater pollution can be identified (Oltean, Goldan, and Nistor 2018). The land’s topography is changed after the mining activity’s closure, and vegetation and fauna are affected, and it impacts local biodiversity (Oltean et al. 2018). It is also a threat to worsen the global environmental problem (Senanayake et al. 2020).
The development of land use/land covers as a manifestation of the structure and function of socio-ecological systems reflects the transformation of regional ecosystems and socioeconomics (Mi et al. 2019). Also, land-use change is a dynamic process driven mainly by natural and artificial phenomena (Le and Jensen 2014). Like air and water quality deterioration, waste-disposal problems, flash flooding, high energy consumption, increasing poverty levels (Sholihah et al. 2020), gravity, perturbations (Ding et al. 2017), growing demand in time and space (Le and Jensen 2014). Land-use change and soil erosion can be accelerated by human activities, such as the expansion of agricultural activities, urbanization, deforestation (Senanayake et al. 2020), any streamflow change (Zhang and Ross 2015), and riverbank mining for sand or clay extraction. Biophysical forces, technological and economic concerns, and institutional and political structures are three causes of land-use changes at varying rates and scales (Senanayake et al., 2020).