Taxocoenosis and Distribution of Nektonic Fauna in the Rice Fields of Kashmir (J and K) India

Abstract

Present study attempts to identify the taxocoenosis and distribution of nektonic fauna harbouring the rice field ecosystems of Kashmir. The main objective of the study was to provide an overview of the nektonic community composition and physicochemical characteristics of flood waters. 6 sites were selected in Kupwara, Bandipora, Budgam, Srinagar, Pulwama and Anantnag districts of valley Kashmir. A total of 26 taxa belonging to 13 different orders were reported during the study which commenced through 2 consecutive crop cycles. The taxocoenosis was dominated by Coleoptera (10 taxa) followed by Hemiptera (3 taxa), Diptera (2 taxa), Diplostraca (2 taxa), Acarina, Anostraca, Anura, Amphipoda, Basommatophora, Cypriniformes, Cyprinodontiformes, Odonata and Pulmonata (1 taxa each). Diversity was calculated using Simpsons Index (D), Simpsons Index of Diversity (1-D), Simpsons Reciprocal Index (1/D), Shannon-Weiner Index (H'), Margalef Richness Index (d) and Evenness Index (e). Kupwara (34 degrees 02'N; 74 degrees 16'E) formed the most diverse site registering a total of 2384 individuals belonging to 24 taxa. A perusal of the primary data related to the physicochemical attributes of flood waters exhibited that average water temperature varied between 19-30 degrees C, average air temperature varied between 21 and 33 degrees C. pH depicted a variation between 6.0 and 9.0, Dissolved Oxygen varied between a minimum of 1.0 mg L(-1) and a maximum of 10 mg L(-1). Free CO2 ranged between 0 mg L(-1) and 6.1 mg(-1). The results pressed the need for recognizing and preserving rice fields as potential habitats for organisms that have successfully adapted to the highly manipulated and eutrophic conditions of rice paddies.