Impact of Anthropogenic Activities on Coastal Landscape Changes in Unawatuna Coastal Zone, Sri Lanka Wasana S.G.S
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IJMS 2018 vol. 5 (2): 139 - 154 International Journal of Multidisciplinary Studies (IJMS) Volume 5, Issue 2, 2018 Impact of Anthropogenic Activities on Coastal Landscape Changes in Unawatuna Coastal Zone, Sri Lanka Wasana S.G.S. and Thennakoon T.M.S.P.K.* Department of Geography, University of Sri Jayewardenepura, Sri Lanka ABSTRACT Coastal landscape changes are an ultimate result of natural factors, population growth and different anthropogenic factors including tourism. Changes in coastal landscape directly influence on the socio-economic, cultural and environment facets at global, regional and local scales. However, unplanned tourism industry highlighted as a main cause for coastal landscape changes. Understanding and quantifying the spatial and temporal dynamics of coastal landscape changes and its driving factors is essential to put forward the right policies and monitoring mechanisms on coastal growth for decision making. Thus, the objectives of this study were to i) analyse the impact of anthropogenic activities on changing coastal landscape in Unawatuna Coastal zone and ii) identify the temporal changes of coastal landscape and it’s in turn effects. The study was conducted in two (02) Grama Nidhari Divisions viz. Unawatuna Central and Yaddehimulla selecting 60 (10%) households out of 600 total households using random sampling method. Questioner surveys, target group discussions and field observations were used as methods of primary data collection. The magnitude of affected geomorphologic features and ecosystems were identified through the analysis of satellite images while changes of coastal landscape in the area were analysed by ArcView GIS. The study found that there was an increased expansion of built up areas in the last 61 years by reducing the coastal vegetation. Some erosion processes and coastal protection methods also highlighted as a driving factors to change coastal landscape. Considering all the observed and analysed data it could be identified that the area has now become the maximum development stage as a tourist area with 52% out of all anthropogenic activities in the area. Further, the study ascertained that within a short period of time from 2002 to 2017, the natural vegetation cover of the shore has been abated and the tendency of build-up areas has been increased. Anthropogenic activities carried out by inhabitants, tourism business people and Department of Coastal Conservation within coastal areas has changed the coastal landscape and which in result to increase the process of coastal erosion. Finally the study concludes that the need of increasing the awareness of all the stakeholders act as driving forces on negative impacts of changing coastal landscape and the importance of preserving the environment. KEYWORDS: Coastal Landscape Change, Unawatuna, Erosion, Tourism, Anthropogenic Corresponding author: Thennakoon T.M.S.P. K., Email:[email protected] Wasana S.G.S. and Thennakoon, T.M.S.P. K. anthropogenic activities have influence 1. INTRODUCTION for it is the subject of this research. Coastal landscape changes is a result from The coast is where a land mass meets the natural factors, population growth and sea (The American Heritage Dictionary, different tourism related activities. 2000).Coastal landscape is shaped by the Changes in coastal landscape directly natural forces of the wind and waves. influence the socio-economic, cultural These geographical forces erode or and environment facets at global, regional construct the natural environment, and local scales. However, unplanned constantly changing its shape. Features of tourism industry highlighted as a main coastal landscapes include beaches, drive to alter or change the coastal dunes, bays, cliffs, platforms, spits and landscape. Although a number of lagoons. Coastal areas are transitional researches have been carried out on the areas between the land and sea coastal and coastal landscape changes characterized by a very high biodiversity with a physical perspective, there are and they include some of the richest and limited researches on the study of most fragile ecosystems on earth, like anthropogenic activities that affect the mangroves and coral reefs. At the same change in landscape of Unawatuna. time, coast are under very high Although a number of researches have population pressure due to rapid been carried out on the coastal and coastal urbanization processes. More than half of landscape changes with a physical the world population live in coastal area perspective at international and local and its number is on the rise. On the other levels, there are limited researches on the hand, coastal areas are those which are study of anthropogenic activities that most visited by tourists and in many affect the change in landscape of coastal areas tourism presents the most Unawatuna. Therefore, this research is a important economic activity. As this considerable contribution to fill the reasons coastal landscape have a huge knowledge gap of coastal landscape impacts by different tourism related changes in Sri Lanka with special activities. reference to anthropogenic activities. Thus, the objectives of this study were to Humans are the guardians of coastal i) analyse the impact of anthropogenic landscape and they have affected them activities on changing coastal landscape both positively and negatively. Some of in Unawatuna Coastal zone and ii) the ways that they have impacted the identify the temporal changes of coastal landscape is by dredging, pollution, landscape and it’s in turn effects. constructing buildings, land reclamation, creation beaches, planting exotic 2 MATERIALS AND METHODS vegetation and trees, erosion sea walls and by destroying natural habitats of wild The study conducted in the coastal area of life. Therefore understanding the coastal Unawatuna. This area represents the landscape change in Unawatuna and how Habaraduwa divisional secretariat in Impact of Anthropogenic Activities on Coastal Landscape Changes in Unawatuna Coastal Zone, Sri Lanka Galle district. There are fifty one Grama constructed to demarcate the changes of Niladari divisions in this divisional geomorphologic units and this was secretariat. Among them, Unawatuna verified through the field works. Aerial Central Grama Niladhari Division and photograph of 1956, 1976, 1986 and 1996 Yaddehimulla Grama Niladhari were pre-processed using ArcGIS. Division’s coastal zones have drastic Comparison of the changes for each year destructions on coastal landforms and was done referring the Google maps 2002 ecosystems due to the anthropogenic to 2017. Buildings near the beach area activities. Hence, Unawatuna coastal were calculated by digitizing Google zone is selected as the study area maps to identify the coastal landscape covering these specific aspects. To fulfil changes. the fair of the study, out of the number of 304 households in Unawatuna Central 3 RESULTS & DISCUSSION GND and 296 of households in Yaddehimulla GND, 60 (10%) 3.1 Existing Anthropogenic Activities in households were selected using random the Study Area sampling method. To achieve the more Generally, the results of this study realistic and correct results, consulting the indicated that there was an increased officers and workers who enrolling with expansion of built up areas in the last 61 the government institute, and Private years by reducing the coastal vegetation. sector owner’s doctrines more essential Some erosion processes and coastal for the study. The sample collected by protection methods also highlighted as a employing judgement sampling method. driving factors to change coastal Required data for this study was collected landscape. Considering all the observed from both primary and secondary sources. and analyzed data, it could be identified For the identification of landscape that the area has now become the changes in the study area, secondary data maximum development stage as a tourist was collected from Habaraduwa area. All the features of under divisional secretariat office, Coastal urbanization such as population growth, Conservation Department and Survey migration pattern highly effected for that Department of Sri Lanka. Questioner dynamism. Among them residence in the surveys, target group discussions and coastal zone, fishing and aquaculture, field observations were carried out as shipping, land use practices (Agriculture, relevant methods for primary data Industrial development and unauthorized collection. The magnitude of affected constructions) are main existing geomorphologic features and ecosystems anthropogenic activities. Another reason were identified through the analysis of for the destruction of the Unawatuna satellite images while changes of coastal Beach is the breakwater that was built by landscape in the area were analysed by the Coast Conservation Department. The using ArcView GIS. Using these data, a breakwater, which stretches nearly a tentative geomorphologic map was kilometre into the ocean has disturbed the natural balance of the eco-system, and is Wasana S.G.S. and Thennakoon, T.M.S.P. K. washing away the sand from one half of many benefits, including biological the beach, and depositing it on the other productivity and ecosystem services as half. highlighted by Turner et al. (1996) and As coastal zone of Unawatuna area Priess and Volk (2012) in other countries. provide a variety of goods and services, The expansion of urban areas as a they have long been used for many consequence of population growth different activities such as settlement, emerges significant