Chapter 2 Study Area
Total Page:16
File Type:pdf, Size:1020Kb
CHAPTER 2 STUDY AREA 2.1.0 INTRODUCTION In the management of water resources groundwater has its own significance in development and planning at various levels. It is important to have a detail insight into approach the geochemical study of the groundwater for planning and management in irrigation, industries and domestic purposes. Impulse of monsoon and withdrawl of groundwater in excess to replenishment of aquifer system in many parts, result in continuous declining of water table causing detoriation in water quality. The study will be absolute only with a detailed background regarding geology, geomorphology, drainage and ecological development of major groundwater potential regions. 2.2.0 LOCATION The area chosen for study is in and around Nagapattinam coastal region, which is situated on the eastern margin of Tamilnadu. The study area extents between Latitude of 10 deg 10 min N to 11 deg 20 min N and Longitude of 79 deg 15 min E to 79 deg 50 min E. The study area falls in the Survey of India toposheets 58 M/11, M/12, M/15, M/16, N/09, N/10, N/11, N/13, N/14 and N/15 with a total area of about 2877 km2. It includes the taluks of Sirkazhi, Mayiladuthurai, Tharangambadi, Nagapattinam, Kilvelur, Thirukkuvalai and Vedaranyam. The area has also been 8 Fig: 2.1 Study Area 9 extended into the Karaikkal Union Territory so as to get a complete overview along the coast. The study area is bounded by Thiruvarur District on the west, Cuddalore district on north, Palk strait on south and Bay of Bengal lies on east of the study area. All the major towns of the study area are well connected to the head quarters, Nagapattinam and with other main cities of Tamil Nadu by metalled roads and railways. 2.3.0 POPULATION As per the Census (2001), the study area has a total population of 15,59,479 which is 2 % of state population. Of the total population, 8,23,429 are male and 8,35,940 are female. 2.4.0 INDUSTRIES The Study area is deprived of any major industry, but it is a flourishing centre of cottage industries and handicrafts alike. This region is equally well known for its pith articles consisting of beautiful models of Hindu idols, temples, mosques, flower garlands, bouquets, parrots and peacocks. The flower garlands and bouquets are much in demand during Christmas days. Pith is grown on the beds of tanks in the Sirkazhi, and Mayuram taluks. The making of musical instruments of jack wood like the veena, the tambura, the violin, the mridangam, the tabla and the kanjara exhibit excellent taste, knowledge and workmanship. The jack wood has special quality for producing musical sounds. Government has established an industrial training institute at Nagapattinam. This is to promote industrial development in the area (www.nagapattinam.tn.nic.in). There were 26 pottery units in Karaikal engaged in the 10 manufacture of utensils, flower pots, water jugs etc. Some of the units also produced tiles in their kilns. In the year, 1823, as many as 100 brick kilns and 71 brick makers were counted. The same report revealed the existence of 35 oil mills manufacturing coconut oil, gingili oil, besides producing oil from elipe (bassia longifolia) and laurel seeds. Of the three soap units, two were located in Karaikal and the other in Tirumalarajanpatinam. The three coir manufacturers in Karaikal engaged lascars or coolies according to the type of coir to be manufactured. They used six different types of looms for the purpose. The work was carried out generally between January and October every year. (www.karaikal.gov.in) 2.5.0 ACCESSIBILITY The region is very much developed in terms of Transport and communications. The nearest airport to Nagapattinam is at Tiruchirappali at distance of about 150 kms. It is well connected to Chennai airport by regular flights. The rail head at Nagapattinam is well within city limits. Nagapattinam is well rail connected to all major cities in India through Chennai and Tiruchirapalli. The Railway stations near Nagapattinam are Kumbakonam (53 km) and Thanjavur (77 km). Bus facilities are available from Nagapattinam to all cities round the clock. 2.6.0 TOURISM Poompuhar (Sirkazhi block), Tharangampadi (Sembanarkoil block), Velankanni (Velankanni block), Nagore (Nagapattinam block) Thirunallar (Karaikkal) and Point Calimere (Vedaranniyam block) are the main tourist spots in the study area. The first 5 tourist spots are visited throughout the year and the 11 last tourist spot is visited from August to March. The foreign tourist arrivals have fluctuations and domestic tourist arrivals have been steadily increasing except in the years 1992-93 and the tourist arrivals both domestic and foreign are estimated at 2,99,150 during 1996. These six tourist spots are also included in the tourist circuits identified by the Tourism Department. 2.7.0 METEOROLOGY 2.7.1 CLIMATE The study area has tropical climate. The summer season starts in the end of March and remains till the advent of monsoons in early June. The average maximum temperature during the summers remains around 35°C. The average minimum temperature is 24.75ºC. The winters are relatively very pleasant when average minimum temperature remains around 20°C. 2.7.2 HUMIDITY The relative humidity of the study area ranges from 70% to 77% and it is high during the period of October and November. 2.7.3 WIND Dust Storms, whirl winds and dusty winds blow from various quarters towards the end of May. The Southwest winds sets in during April, it is the strongest in June and continues till September. Northeast monsoon starts during the month of October and blow till January. Cyclonic storm with varying wind velocity affects once in 3 or 12 4 years during the month of November-December. Both these storms affect the plantation crop. During Southwest monsoon the air is calm and undisturbed. 2.7.4 RAINFALL The district receives rainfall under the influence of both southwest and northeast monsoon. A good part of the rainfall occurs as very intensive storms resulting mainly from cyclones generated in the Bay of Bengal especially during northeast monsoon. The Northeast monsoon , which starts in October and ends in December, contributes about 60% of the total annual rainfall. The Southwest monsoon rains from June to September and from March to May accounts equally for the rest of the annual rainfall. The district receives rainfall almost throughout the year. Rainfall data analyzed (period 1901-70) shows the normal annual rainfall of the district is 1230 mm. The monthly average rainfall in the district was 108.87 mm in 1991-96. The rainfall pattern in the study area shows interesting features. Annual rainfall, which is 1500 mm at Vedaranyam, the southeast corner of the district, rapidly decreases to about 1100 mm towards west of the district. The district enjoys humid and tropical climate with hot summers, significant to mild winters and moderate to heavy rainfall. The rainfall distribution was studied in seven different locations of 1.Nagapattinam, 2.Thirupoondi, 3.Thalagnayiru, 4.Thrangampadi, 5.Sirkazhi, 6.Mayiladuthurai and 7.Vedaranyam during 2000 and 6 locations of 1.Nagapattinam, 2.Thirupoondi, 3.Thalagnayiru, 4.Tharangampadi, 5.Sirkazhi and 6.Mayiladuthurai during 2009. The total rainfall obtained from these observation stations during 2000 account for about 11345.1mm, and that during 2009 accounts for about 8635.9mm. 13 Fig.2.2 Rainfall for 2000 Fig.2.3 Rainfall for 2009 14 Hence it is understood that the region had experienced heavier rainfall during 2000 than 2009. The rainfall was dominant in both the monsoons at all the stations during 2000, but during 2009 only NE monsoon was predominant. Some of the researchers have identified that the decrease in vegetation cover has resulted in decrease of rainfall (Sarma, 2001; Dengiz et al., 2009). 2.8.0 GEOMORPHOLOGY The present geomorphic set up in the study area is the result of action of the major rivers with their distinct tributaries, oscillations in the sea level, tidal effects of Bay of Bengal and forces of wind. This forms a part of the fertile Cauveri delta and the region is completely covered by the distributaries of Cauveri. The landforms are delineated under erosional and depositional regime. The depositional regime comprises of a coastal plain under marine influence, a flood plain of fluvial regime with an intermixing section of both fluvial and marine influence. The study area is covered completely by a mantle of alluvium of variable thickness, the region is flat having a gentle slope towards the Bay of Bengal in the east. The entire area is a peneplained terrain with a gentle slope towards east and southeast. The maximum elevation is about 21 m above mean sea level in the west. The geomorphology consists of the younger coastal plain which acts on a margin between the older coastal plain and the Bay of Bengal. Alluvial plain is noted along the coast in the central part of the study area which extends inward in both North and South directions. The plain occupies the major part of the study area. There are also flood plains noted along the river course. This area also has sand dunes and paleo 15 Fig: 2.4 Geomorphology of the study area 16 beach ridges. The Cauvery and its offshoots are the principal rivers. Rising in the Coorg Mountains, this river bifurcates about nine miles at the west of Trichy into two branches, of which the northern one takes the name of Coleroen and the southern one retains that of the Cauvery. All along the course of Cauvery and its dis-tributaries, on both the banks numerous narrow strips of river porombokes lands called Paduagais that are cut up by countless patta lands.