DISTRICT SURVEY REPORT Perambalur district is a centrally located inland district of Tamilnadu, spread over 3690.07 sq.kms, which was trifurcated from the erstwhile composite Tiruchirappalli district and was formed on 1 November 1995. The district is bounded by Cuddalore district in the North, Tiruchirappalli district in the South, Thanjavur in the East and Namakkal and Tiruchirappalli districts in the West. Perambalur District lies in the geographical co-ordinates of East longitude 78o36’ and 79o31’ and North latitude 10o51’ and 10o31’. The district for administrative purpose has been divided into six Taluks (Perambalur, Kunnam, Veppanthattai, Ariyalur, Sendurai and Jayakondam), which is further sub-divided into ten blocks viz. Table 1: Area and Extent of Panchayat unions in different taluks Extent of No. of revenue SI.No. Taluks Panchayat unions taluks (ha) villages 1. Ariyalur 1. Ariyalur 67,650 68 2. Thirumanoor 3. Veppur . 2. Kunnam 84,680 80 4. Alathur 3. Perambalur 5. Perambalur 33,684 26 4. Sendurai 6. Sendurai 31,452 28 7. Jeyamkondam 5. Udaiyarpalaiyam 8. T.Pazhur 94,269 96 9. Andimadam 6. Veppanthattai 10.Veppanthattai 57,372 38 Total 3,69,107 336 Perambalur, Veppanthattai, Veppur, Alathur, Ariyalur, Thirumanur, Sendurai, Jayakondam, Andimadam and T.Palur) comprising of 327 Villages, 322 Village Panchayats and nine Town Panchayats. POPULATION The total population of the district as per 2001 census is 11,81,029 of which 5,88,441 are males and 5,92,588 are females. The sex ratio is 1007 with the birth rate at 21.6 and the death rate at 7.7. The density of population of the district per sq.km is 281 persons as against the state average of 429 persons. (Census,2001) RAINFALL The annual distribution of rainfall in all the six taluks of Perambalur district over a period of 70 years is furnished below: Table 2: Average Rainfall pattern for a period of 70 years in the study area. Seasonal rainfall Mean annual South West North East S.No. Taluks Winter Summer rainfall Monsoon Monsoon (June - Sep) (Oct - Dee) (Jan - Feb) (Mar - May) (mm) mm % mm % Mm % mm % 1. Ariyalur 829 328 39.6 381 45.9 23 2.8 97 11.7 2. Kunnam 832 306 36.8 414 49.8 23 2.7 88 10.7 3. Perambalur 952 220 23.2 589 61.8 30 3.2 112 11.8 4. Sendurai 923 324 35.1 503 54.5 22 2.4 74 8.0 5. Udaiyarpalaiyam 1110 418 37.7 570 51.3 43 3.9 79 7.1 6. Veppanthattai 801 284 35.5 394 49.1 26 3.3 97 12.1 The data shows that on an average the amount of rainfall received remains to be the same. It is also evident rainfall is received in all four periods of which the maximum rainfall is during Northeast Monsoon, followed by southwest monsoon and the minimum rainfall was noted in winter. The average rainfall in the district shows a minor increasing trend with less slope (Figure). The increase in rainfall results in accelerated erosion factors under favourable conditions. Figure. Rainfall pattern in Perambalur District. TEMPERATURE The atmospheric temperature data recorded over a period of 70 years (1927 - 1996) was computed and the mean maximum and mean minimum temperature were arrived using graph. It is seen that the not months are April, May and June with the maximum temperature ranging from 38° to 39°C and the cool months being January and February with the minimum temperature ranging from 20°C to 21°C. Monthly Temperature (oC) Temperature (oC) SI. No. Months Maximum Minimum Mean 1. January 31.0 20.0 25.5 2. February 34.0 21.0 27.5 3. March 35.0 23.0 29.0 4. April 38.0 25.0 31.5 5. May 39.0 27.0 33.0 6. June 38.0 26.0 32.0 7. July 36.0 26.0 31.0 8. August 36.0 27.0 31.5 9. September 36.0 24.0 30.0 10. October 35.0 24.0 29.5 11. November 33.0 23.0 28.0 12. December 30.0 21.0 25.5 DRAINAGE In this district, Vellar is the important river flowing and substantially benefiting agricultural activities. The Vellar river rises from Salem district and forms boundary between Perambalur and Cuddalore district . The Marudaiyar river traverse through Ariyalur taluk and empties in to the Coleroon river. Kallar and Chinnar, which are tributaries of Vellar and Marudaiyar rivers, traversing through Perambalur taluk and Kallar and Marudaiyar in Udaiyarpalaiyam taluk benefit the agricultural activity (Table 4). Table 4. The details of river basins in Perambalur District SI. Watershed River Basins Taluks No. Code 1 4B1A5 Kollidam - Veeranam Perambalur & Udayarpalayam Perambalur, Ariyalur, 2 4B1A6 Marudaiyar Udayarpalayam 3 4B1A7 Nandiyar Perambalur 4 4B1B2 Ayyaru Perambalur 5 4C1A6 Chinnar Perambalur & Udayarpalayam 6 4C1A8 Kallar Perambalur GEOMORPHOLOGY The general Physiographic of this district is versatile with hill ranges, series of plains, valley bottoms undulating upland area and broken chains of Eastern Ghats viz., Pachamalai hills. A part of Pachamalai hill is the important hill, in Perambalur taluk of this district. The average height of Pachamalai hill is 600 me though a few of the peaks rise to about 1020 metres above Mean Sea Level. But for this hill, Perambalur forms a gentle undulating upland and having hilly areas, gullied lands and small hillocks. While Udaiyarpalaiyam taluk is fair1y flat and the southern end is very gently sloping. Ariyalur taluk is having slightly elevated (Figure), undulated area on the north-western portion and rock out crops in central eastern part. Figure. Spatial distribution of different Geomorphic features Spatial distribution of different Geomorphis features Alluvial Plain Buried Pediment Erosional Surface Low Land Cretaceous Pediment Shallow Pediment Structural Hills Up Land Tertiary Valley Fill GEOLOGY Perambalur district is geologically made up of Archaean, cretaceous, tertiary and quaternary formation. Formations of upper Gondwana age are also found in a limited extent. The Archaeans consist of biotite and, hornblende gneisses, charnockites etc., Upper jurassic formations are represented by equivalents of Gondwana in small patches in parts of Perambalur taluk. The sequence of beds of cretaceous age of Thiruchirappali commences with Uttatur stage and ends with Niniyur stage. To the south and north they are covered by alluvial deposits and to the east by the Cuddalore sand stone of Miocene age. In Tertiary, the Miocene and Pliocene members are well developed. The Miocene formation consists of alternate layers of sand and clay. The sand layers are usually found to be more clay bound. They are also ferrugenous in nature. The Pliocene consists of alternating sands and clay beds of limited extent. Mineral Resources: The district is quite rich in minerals like limestone, clays, clayey sand stones etc., the details are given below: 1. Clays: Upper Gondwana, formation is represented by clays, which are having economic values. These clays are used locally for superior type of pottery and also for the manufacture of salt glazed pipes, fine bricks and electrical insulators. Alluvial clays of Kollidam river and sandy clays occuring over Cuddalore sand stone, are used locally for bricks making. 2. Lime stone: Sedimentary lime stone occurring as cretaceous formations and is estimated 2,26,000 tonnes of 50% CaO and 17 million tonnes of 42 to 46% CaO also found in Ariyalur taluk. IKunnam taluk, 3,00,000 tonnes of 50% CaO is also found. 3. Garnet: Garnet sand concretions occur on the Eastern and Northern sides. Massive garnet, is reported to occur in crystalline lime stone in Perambalur taluk. LINEAMENTS Lineaments are the weaker zones identified from the imageries. There are two set of lineaments noticed in the study area. First type is NE-SW and the other is NE-SE of these the first type is more prominent and it is represented in almost 2/3 of the study area falling prominently in the western part covering the hard rock and the limestone terrain. The sandstone region is prominently with the second set of lineament. HYDROGEOLOGY A study conducted by Public Works Department of Tamilnadu (2002) states that the thickness of the aquifer in the district varies from 15 to 35 MBGL. The wells in the alluvial formation have good yield of about 300 – 950 lpm, sandstone 300-350 lpm and the hard rock 80-210lpm. LANDUSE PATTERN In this district, out of the total geographical extent of 3,69,107 hectares only 2,38,814 hectares (64.70%) are used for agricultural purposes. A total of 32,933 hectares (8.92%) are kept as fallow lands. The lands-put to non- agricultural purposes occupy 43,953 (11.91 %) hectares. The cultivable wastelands of 7,742 (2.10%) hectares can be brought in to agricultural uses by suitable measures. MINES The total limestone reserves are about 1,473 million tonnes. There are 12 major cement plants functioning in the State. The major players are Tamil Nadu Cements (TANCEM), Dalmia Cements, Madras Cements, India Cements, Grasim Industries, Associated Cement Companies and Chettinad Cements. Perambalur district is geologically made up of Archean, Cretaceous, Tertiary and Quaternary formations. Among sequence of beds of cretaceous age, Limestone occur as sedimentary formation and is estimated 2,26,000 tonnes of 50% Calcium Oxide (Ca O) and 17 million tones of 42% to 46% Calcium Oxide are found in Ariyalur - Sendurai Taluks. 3,00,000 tonnes of 50% Calcium Oxide also found in Kunnam Taluk. The exploited mineral limestone is being utilized in the cement plants of Ariyalur, Trichirappalli and Perambalur. Superior grade fireclay, used for manufacturing flooring tiles, stoneware pipes, firebricks etc., is available in parts of Kunnam Taluk.