Study area and sampling
Thanjavur is located in the centre-east
of Tamil Nadu state, India (Lat. 10°47’ N;
Long. 79°10’ N). Thanjavur district occupies
3,205 sq miles [8,300 sq km] in area in the
part of flat, fertile Cauvery Delta region,
which is one of the most important ricegrowing
areas in India. There are several
natural and artificial (temple) fresh water
ponds are distributed more frequently in and