Project Personnel Dr. Srikumar Chattopadhyay : Principal Investigator Sangeetha P.Viswan : Project Fellow L.Asa Rani : Project Fellow Acknowledgement This project was funded by Kerala Research Programme for Local Level Development (KRPLLD), Centre for Development Studies, Thiruvananthapuram. We are grateful to Dr. K. Narayanan Nair, Programme Coordinator, KRPLLD for sanctioning this project. We are thankful to Dr. M.Baba, Director, Centre for Earth Science Studies for permission to take up this project and providing facilities to execute it. Dr. K.Soman, Head, Resources Analysis Division (RAD) is thanked for extending facilities. Smt. Mahamaya Chattopadhyay, Scientist, RAD was thanked for providing useful suggestions related to morphometric analysis. Dr.P.P. Ouseph, Head, Chemical Sciences Division (CSD) is thanked for extending laboratory facilities. Sri. C.S. Satheesh Kumar and Sri. V. Raviendren, Project Fellows, CSD assisted in water sample collection and laboratory analysis. Smt. Asha, Y.A., Sri. Manu.M.Nair and Smt. Sreelekha, C., Project Fellows of RAD took part in GIS application. Sri. Sooraj. S, Assistant Geologist, Department of Mining and Geology helped during field work. Smt.Sudha. S attended to drafting of maps. Ms.Reema Rani, M.V. did the typographical job. Smt. A.Balkeez provided secretarial assistance. Services rendered by all of them are highly appreciated. Sri. P. Ramachandran Nair, Driver is thanked for help during field work. A large number of local people assisted us during field survey. We take this opportunity to thank all of them for their services. CONTENTS Page No. Chapter 1 Introduction 1 1.1 Introduction 1 1.2 Objectives 3 1.3 Hypothesis 4 1.4 Methodology and data source 6 1.5 Organisation of the Report 7 Chapter 2 Study area and its overall characteristics 8 2.1 Introduction 8 2.2 Physiography 8 2.3 Climate 11 2.3.1 Rainfall 11 2.3.2 Temperature 15 2.3.3 Relative Humidity 15 2.3.4 Evappotranspiration 16 2.4 Geology 16 2.5 Geomorphology 16 2.6 Terrain 21 2.7 Hydrogeomorphology 21 2.8 Morpho-conservation 25 2.9 Drainage 26 2.10 Soil 29 2.11 Land capability 31 2.12 Irrigability 32 2.13 Natural vegetation 33 2.14 Irrigation 36 2.15 General landuse 40 2.16 Agriculture 42 2.16.1 Distribution of seasonal crops 43 2.16.2 Distribution of tree crops 45 2.16.3 Distribution of plantation crops 45 2.16.4 Crop combination 46 2.16.4.1 Crop combination – seasonal crops 46 2.16.4.2 Crop combination – tree crops 48 2.16.4.3 Crop combination – total cropped area 49 2.16.5 Crop intensity – paddy 52 2.16.6 Distribution of paddy 52 2.16.7 Distribution of coconut 54 2.16.8 Distribution of rubber 54 2.17 Population 54 2.17.1 Distribution of population 55 2.17.2 Growth of population 57 2.17.3 Density of population 60 2.18 Occupational structure 63 2.19 Selection of sample site 64 Chapter 3 Landscape/landuse change 68 3.1 Introduction 68 3.2 Landuse change 68 3.2.1 The confluence of the Chalakudi and the Periyar river and surroundings 69 3.2.2 Chalakudi town and surroundings 76 3.2.3 Thumburmuzhi and surroundings 82 3.2.4 Parambikulam reservoir area 88 3.2.5 Lower Karapara river area 91 3.3 Landscape change 95 3.3.1 The confluence of the Chalakudi and the Periyar river and surroundings 95 3.3.2 Chalakudi town and surroundings 98 3.3.3 Thumburmuzhi and surroundings 101 Chapter 4 Environmental impacts/consequences 104 4.1 Introduction 104 4.2 Quality of river water 104 4.3 River zonation 125 4.4 Quality of well water 133 4.5 Groundwater zonation 146 4.6 Impact on well water depth and fluctuation 146 4.6.1 Water table contour 150 4.6.1.1 Depth to water level, November, 2001 150 4.6.1.2 Depth to water level, March, 2002 150 4.6.1.3 Depth to water level, June, 2002 154 4.6.1.4 Depth to water level, July, 2003 154 4.6.2 Water table fluctuations 154 4.6.2.1 Water table fluctuation – November, 2001-March, 2002 154 4.6.2.2 Water table fluctuation – March, 2002-June, 2002 154 4.6.2.3 Water table fluctuation – November, 2001-June, 2002 156 4.6.2.4 Water table fluctuation – June, 2002-July, 2003 158 Chapter 5 Landuse/Landscape change: Causes and consequences – Local people’s perception 159 5.1 Introduction 159 5.2 Sample survey procedure 159 5.3 Identification particulars 160 5.4 Household information 160 5.5 Amenities in the house 162 5.6 Details of land possessed, agriculture and allied activities 162 5.6.1 Landuse conversion 163 5.6.2 Reasons for landuse conversion 166 5.6.3 Years of landuse conversion 167 5.6.4 Economic background and landuse conversion 168 5.6.5 Landuse conversion and size of holdings 169 5.6.6 Economic background and landuse type 170 5.6.7 Landuse conversion and land type 170 5.6.8 Agricultural profit and landuse conversion 171 5.6.9 Landuse conversion and land value 173 5.6.10 Impact of landuse conversion 173 5.6.10.1 Groundwater and surface water 174 5.6.10.2 Sand mining 175 5.6.10.3 Clay mining 175 5.7 Around Parambikulam reservoir 176 5.8 Around lower Karapara river 178 5.9 PRA Analysis 178 Chapter 6 Testing of Hypothesis 180 6.1 Introduction 180 6.2 Hypothesis-1 180 6.3 Hypothesis-2 181 6.4 Hypothesis-3 183 6.5 Hypothesis-4 185 Chapter 7 Conclusion 188 7.1 Conclusion 188 7.2 Recommendations 197 Reference Appendix List of Tables Table No. Page No. 2.1 Monthly average rainfall (mm) (1980-2002), Chalakudi river basin 12 2.2 Monthly average temperature (0C), (1982-’83 to 1987-’88), Chalakudi river basin 17 2.3 Monthly average humidity (%), (1982-’83 to 1987-’88), Chalakudi river basin 17 2.4 Monthly average evapotranspiration (mm) (1980-’81 to 1987-’88), Chalakudi river basin 17 2.5 Geomorphologic units and their areal extent, Chalakudi river basin 19 2.6 Terrain units and their characteristics, Chalakudi river basin 23 2.7 Hydrogeomorphologic features of the Chalakudi river basin 24 2.8 Area distribution under each slope class, Chalakudi river basin 25 2.9 Morphometric parameters, Chalakudi river basin 28 2.10 Some observations about morphometric anomaly, Chalakudi river basin 28 2.11 Soil types and their description, Chalakudi river basin 29 2.12 Land capability classes and their areal extent, Chalakudi river basin 31 2.13 Land irrigability classes and their areal extent, Chalakudi river basin 32 2.14 Areal extent of forest, non-forest and plantation, Chalakudi river basin 34 2.15 Length of canal and ayacut area under right bank canal (RBC) system: Chalakudi irrigation project 37 2.16 Length of canal and ayacut area under left bank canal (LBC) system: Chalakudi irrigation project 38 2.17 Canal length and ayacut area served by main and branch canal under Chalakudi irrigation project 39 2.18 Distribution of ayacut area in some selected panchayats, Chalakudi river basin 39 2.19 Landuse categories and their areal extent – Chalakudi river basin (1966-’67) 41 2.20 Landuse categories and their areal extent – Chalakudi river basin (1997) 42 2.21 Area under different crop groups (1996), Chalakudi river basin 44 2.22 Distribution of major crops (1996) Chalakudi river basin 47 2.23 Crop combination – seasonal crops, Chalakudi river basin 48 2.24 Crop Combination –tree crops, Chalakudi river basin 49 2.25 Crop combination –total cropped area, Chalakudi river basin 50 2.26 Distribution of population (percentage to total population of the basin), Chalakudi river basin 57 2.27 Growth of population, Chalakudi river basin 59 2.28 Density of population, Chalakudi river basin 61 2.29 Sectoral distribution of workers, Chalakudi river basin 66 2.30 Sample sites, panchayats and their demographic characteristics (Selected), Chalakudi river basin 67 3.1 Landuse categories and their areal extent – around the Confluence of the Chalakudi and the Periyar 70 3.2 Landuse conversion matrix – around the Confluence of the Chalakudi and the Periyar (1980-2003) 72 3.3 Landuse categories and their areal extent – in and around Chalakudi town 77 3.4 Landuse Conversion matrix – in and around Chalakudi town (1980-2003) 81 3.5 Landuse categories and their areal extent – in and around Thumburmuzhi 83 3.6 Landuse Conversion matrix – in and around Thumburmuzhi (1980-2003) 85 3.7 Landuse categories and their areal extent – around Parambikulam Reservoir 88 3.8 Landuse Conversion matrix – around Parambikulam reservoir (1975-2003) 91 3.9 Landuse categories and their areal extent – around lower Karapara river 92 3.10 Landuse conversion matrix – around lower Karapara river (1975-2003) 92 3.11 Landscape categories and their areal extent – around the Confluence of the Chalakudi and the Periyar 96 3.12 Landscape conversion matrix – around the Confluence of the Chalakudi and the Periyar (1980-2003) 98 3.13 Landscape categories and their areal extent – in and around Chalakudi town 99 3.14 Landscape conversion matrix – in and around Chalakudi town (1980-2003) 101 3.15 Landscape categories and their areal extent – in and around Thumburmuzhi 102 3.16 Landscape conversion matrix – in and around Thumburmuzhi (1980-2003) 102 4.1 Description about the river water sampling sites, Chalakudi river basin 106 4.2 Physico-chemical parameters – Chalakudi river basin, July, 2001 108 4.3 Physico-chemical parameters – Chalakudi river basin, August, 2001 109 4.4 Microbiological analysis – Chalakudi river basin, August, 2001 110 4.5 Physico-chemical parameters – Chalakudi river basin, November, 2001 111 4.6 Microbiological analysis – Chalakudi river basin, November, 2001 112 4.7 Physico-chemical parameters – Chalakudi river basin, March, 2002 114 4.8 Microbiological analysis – Chalakudi river basin, March, 2002 115 4.9 Physico-chemical parameters – Chalakudi river basin, June,