THE NILGIRIS DISTRICT: MODIFICATIONS OF HILL ENVIRONMENT AND IMPLICATIONS USING GEO-SPATIAL TECHNIQUES Thesis submitted to the Bharathidasan University for the award of degree of Doctor of Philosophy in Geography Submitted by J.Murugesan, Assistant Professor and Part – Time Research Scholar, Research Supervisor Dr.P.H.Anand, M.Sc.,M.Phil.,Ph.D. Associate Professor and Head Post Graduate and Research Department of Geography, Government Arts College (Autonomous), Kumbakonam – 612 001, Tamil Nadu, India September – 2013 1 DECLARATION I do hereby declare that the thesis entitled “THE NILGIRIS DISTRICT: MODIFICATIONS OF HILL ENVIRONMENT AND IMPLICATIONS USING GEO-SPATIAL TECHNIQUES”, which I am submitting for the award of Degree of Doctor of Philosophy in Geography, to the Bharathidasan University, is the original work carried out by me, in the Post Graduate and Research Department of Geography, Government Arts College (Autonomous), Kumbakonam 612 001, Tamil Nadu, India, under the guidance and supervision of Dr. P.H. Anand, Associate Professor and Head, PG and Research Department of Geography, Government Arts College (Autonomous), Kumbakonam. I further declare that this work has not been submitted earlier in this or any other University and does not form the basis for the award of any other degree or diploma. Kumbakonam J.Murugesan 16th September 2013 Part-time Research Scholar 2 PG and Research Department of Geography (DST-FIST Recognized) Government Arts College (Autonomous), (Accredited by NAAC // AICTE and Affiliated to Bharathidasan University)) Kumbakonam, 612 001, Tamil Nadu Dr.P.H.Anand,M.Sc.,M.Phil.,Ph.D. 16-09-2013 Associate Professor and Head, CERTIFICATE This is to certify that the thesis entitled “THE NILGIRIS DISTRICT: MODIFICATIONS OF HILL ENVIRONMENT AND IMPLICATIONS USING GEO-SPATIAL TECHNIQUES”, submitted by Mr. J. Murugesan, for the award of Doctor of Philosophy in Geography, in the Bharathidasan University was carried out at the Post Graduate and Research Department of Geography, Government Arts College (Autonomous), Kumbakonam, 612001 under my guidance and supervision after fulfilling the basic requirements specified by the University. (P.H. ANAND) Research Advisor 3 Acknowledgement The relationship between the natural environment and human culture is a two- way street. Too often, only one part is asserted: that the form of the natural environment influences (or, in extreme cases, determines) the human culture of a place. Mountains may prove obstacles to communication, but transport technology overcomes the barriers. Climate may limit the growth of certain crops, but irrigation or greenhouse protection can extend a plant’s natural limits. That is not to say that the natural environment does not pose risks: hurricanes, earthquakes, volcanic eruptions, or droughts all pose risks to human settlement. But as human technology expands, people are able to adapt to the constraints once placed by the natural environment. Besides technological adaptation, human culture has increasingly modified the natural environment, shaping it to its needs. Clearing forests for agriculture, paving surfaces for urban areas, damming rivers, exploiting minerals, polluting air, streams and oceans, are all examples of the permanent changes to the natural world resulting from human culture.Places are the resolution of the forces of nature and adaptations by human culture. Moreover, as this relationship changes over time, so too do places. Rather than simply comparing the nature of the physical environment with what people do with it, students should consider human perception. Thus, an environment may be considered hazardous by an objective observer, but explaining human adaptation involves knowing how the environment is perceived 4 by those who use it. People might not be expected to settle on the sides of active volcanoes, as in Central America, or build on the shores of hurricane-prone coasts – that they do requires understanding how they perceive the environment and deal with the risk. The present research is focused on the Modifications of Hill Environment considering the Nilgiris District as a Spatial Unit. At the outset I thank our Principal Dr. K. Mohanasundaram, Government Arts College (Autonomous), Kumbakonam, for extending moral and administrative support for the successful completion of this work. I remember the similar support, which was extended to me by the then Principal-in-charges of this college, during their tenure. I convey my sincere thanks to Prof. I.C. Kamarajand Prof. V. Kumaraswamy, former Heads of the Department of Geography, for consistent encouragement and critical suggestions as and when I approach them. I wish to express my deepest gratitude to Dr. P.H. Anand, Associate Professor and Head, P.G and Research Department of Geography, Government Arts College (Autonomous), Kumbakonam for his unencumbered, exemplary guidance, indefatigable efforts to steer in the right direction, bountiful scholarly advice, undiminished zeal for extracting fruitful information and for his painstaking efforts and deepest understanding of my needs in this research. I extend my sincere thanks to Dr. P. Thirumalai and Dr. J.Senthil, Assistant Professors of Geography, P.G and Research Department of 5 Geography, Government Arts college (Autonomous), Kumbakonam for giving a good shape to this project. I also convey my deep sense of gratitude to my colleagues, Dr. P. Arul, Dr. B. Gobu, Dr. R. Maniyosai, Thiru. K.K. Jayakumar, and Thiru. A. Senthilvelan. I appreciate the students of M.Sc., Geography, of this college for the assistance during research work. I convey my deep sense of gratitude to Dr.K.Sekar, the present Principal of the Periyar EVR College (Autonomous), Tiruchirapalli, for the moral and administrative support, which enabled me to produce this kind of peace of work. I acknowledge my sincere thanks and regards to my teachers Professor A. Padmavathy, Professor. M.K.Mariapillai, Professor. M. Subramanian, Professor. M.RajasekaranRatnakumar, Professor. N.Nanjundan, Department of Geography, Periyar EVR College (Autonomous), Tiruchirapalli and Professor SheelaGnanasironmani, then Principal of the Government Arts College, Tiruvarambur, Professor. L.Chellappa, then Principal, MannarSerfoji Government Arts College (Autonomous), Dr.M.Pannerselvam, then Principal, Manar Durisingam Government Arts College for Men, Sivaganga, for their inspiration and continued support as a teacher and a co-fellow of the teaching faculty. I thank my colleague Professor T. Kannadhasan, Head of the Department of Computer Science, Periyar EVR College (Autonomous), 6 Tiruchirapalli, for the support services rendered during the preparation of the thesis work. I personally thank my colleagues in the Department of Geography, Professor. N.HajeeranBeevi, Dr. S.Balaselvakumar, Professor. P. Dhanalakshmi and Dr. T. Pavendar for their continued encouragement during preparation of this research work. I also convey my sincere thanks to my transferred colleagues Professor P .Ravikumar and Professor K. Sumesh, presently working at Government Arts College (Autonomous), Coimbatore for their continued support and guidance. I register my sincere thanks and gratitude to Shri. P. Alaguraja, Research Scholar, Department of Geology of the Bharathidasan University, Tiruchirapalli for his timely help and logistic support during the preparation of this research work. Finally I thank my parents for their whole-hearted support and my grateful thanks and deepest appreciation to my sister Mrs. D.Palaniyammal, for her devotion, sacrifice and continual encouragement throughout the long years of my education. J.Murugesan 7 Sl. No. Contents Page No. Chapter One Conceptual Development of the Problem 1.1 The Nilgiris: A Prologue 12 1.2 Literature Review 12 1.3 Natural hazards and geomorphology 15 1.4 Natural disasters and geomorphology 18 1.5 Geomorphology, vulnerability and disasters 22 1.6 Remote Sensing 33 1.7 Medical and Public Health 35 1.8 Present Study 36 1.9 Objectives 37 1.10 Methodology 37 1.11 Organisation of the thesis 38 Chapter Two Nilgiris Environment: Profile of the Study Area 2.1 The Nilgiris - A Profile 39 2.2 Administrative Set-up 40 2.3 Historical Development of Nilgiris 41 2.4 Geomorphology 43 2.5 Climate 44 2.5.1 Rainfall 44 2.5.2 Minor Irrigation 45 2.6 Demography 46 2.6.1 Literacy 46 2.6.2 Occupational Structure 46 2.6.3 Birth Rate and Death Rate 47 2.7 Land Holding Pattern 47 2.8 Eco-regions 48 2.9 Flora and Fauna 49 2.10 Forests 50 2.11 Agriculture 51 2.12 Industries 52 2.13 Trade and Commerce 53 2.13.1 Transport and Communication 53 2.13.2 Transport Network 53 2.14 Hill Area Development Programme in the Nilgiris 55 2.14.1 Approach of Implementation 56 2.14.2 Major Thrust 57 2.14.3 Integrated Watershed Management in the Nilgiris 58 2.14.4 Implementation Strategy 59 8 2.14.5 Soil Conservation 60 2.15 Beneficiary Contribution 61 2.15.1 Forestry 62 2.15.2 Horticulture 64 2.15.3 Sericulture 65 2.15.4 Animal Husbandry and Dairy Development 66 2.15.5 Energy Conservation 67 2.16 Development of Local Bodies 68 2.17 Human Resources Development 69 2.18 Scheduled Tribes 70 2.19 Tourism 72 2.19.2 Tourism Potential 72 Chapter Three The Slope Instability due to Natural Hazard 3.1 Introduction 73 3.2 Environmental Issues 76 3.3 Remote Sensing for Landslide Location and Causes 79 3.3.1 Detection and Classification of Landslides 79 3.3.2 Monitoring Landslide Movement 80 3.3.3 Landslide Hazard Analysis Mapping 80 3.3.4 Analysis and Prediction of Landslides in GIS 80 3.4 GIS Modeling