## 2 Study Site Description  
The selected study site is part of the northern coastal zone of Ramanathapuram district, as shown in Figure 1, and covers an area of 739 km\({}^{2}\) with a 52 km-long coastline. The Ramanathapuram district is surrounded by the districts of Pudukkottai to the north, Sivagangai to the northwest, Virudhunagar and Tuticorin to the west, the Gulf of Manner to the south, and the Bay of Bengal and the Falk Strait to the east. A coastal strip projects as Rameswaram Island, which is separated from the mainland by the Falk Strait. The district's headquarters are located in Ramanathapuram. It lies between 9\({}^{\circ}\)05\({}^{\prime}\) N and 10\({}^{\circ}\)0\({}^{\prime}\) N latitude and 78\({}^{\circ}\)10\({}^{\prime}\) E and 79\({}^{\circ}\)30\({}^{\prime}\) E longitude, with the study area lying between 9\({}^{\circ}\)30\({}^{\prime}\)-9\({}^{\circ}\)58\({}^{\prime}\) latitude and 78\({}^{\circ}\)50\({}^{\prime}\)-78\({}^{\circ}\)10\({}^{\prime}\) longitude. The topography of the district is generally flat terrain. The main rivers in the district are the Vaigai and the Gundar. During the summer season, these rivers are usually dry. The district covers a geographical area of 4207.38 km\({}^{2}\). The prevailing tropical climate is typical for this region. The district is characterized by a high level of aridity. A cool sea wind blows along the coastal belt.  
The hottest months are April to June, with temperatures reaching 41 \({}^{\circ}\)C and considerable humidity. The average temperature is between 25.9\({}^{\circ}\) and 30.6 \({}^{\circ}\)C, with a humidity level of 79%. Due to its location, the cold season is barely noticeable from December to January. Each year, the study region receives an average of 827 mm of rain. The district receives the most rain during the northeast monsoon, with an average of 525.17 mm (63.5%), followed by the southwest monsoon, with an average of 127.29 mm (15.39%). Summer rainfall during the hot season is 98.36 mm (11.89%). The lowest amount of rainfall occurs in the cool season, with 76.18 mm (9.2%). It is clear that a considerable amount of precipitation falls during the two monsoon seasons. The relative humidity ranges from 73 to 85% throughout the year, especially in the coastal belt of the districts. In the summer season, the humidity is slightly lower in the inner parts of the district. It is noted that the relative humidity is highest in November (85%), which coincides with the highest rainfall. The lowest relative humidity is measured in August (73%). In general, the relative humidity is high in October, November, and December. The monitoring of temperature, precipitation, and relative humidity in the study area suggests that the district has a high temperature and good relative humidity. The  
Figure 1: The sample locations in the study area map.  
agricultural activities and prosperity of the people depend on the monsoon rainfall. The Ramanathapuram district is divided into four separate sections. They are (i) the western and northwestern parts of the district, which are coincident with Archean crystalline rocks, (ii) the central part of the western area, which forms the flat highlands with an elevation of 9.30 m to 20 m, (iii) the western black soil plains of the Paramakudi, Mudukulathur, Ramanathapuram, and Thiruvadanai taluks, and (iv) the Chettinad plain, which is red soil and drained by the Virsuli and Pambar rivers, while the Manimuthar river flows in parts of Thiruvadanai taluk [42; 43; 44; 45; 46].