Composition and structure of the communities of aquatic organisms associated to the waterlogged stages of the rice crop

In the researches about man-made wetlands as substitute for natural wetlands the study of resources availability for conservationist's importance groups has gained an special interest. The present study, in South of the Jibaro, Sancti Spiritus, Cuba, had the objective to made a characterization of the structure and composition of aquatic communities in different stages of the cultivation of the rice and to discuss its implications for the aquatic birds. 55 samples of aquatic animals in parcels of 5 x 0,75 m were collected in the fields preparing for sowing, small green rice, green gleaning, mature rice and in cut and flooded fields. Density and biomass per hectare was determined, and diversity index (H') was calculated, and the dominant guilds were identified. The numeric dominant group is Coleoptera, present in the preparing for sowing, flooded green and cut rice. Other predominant groups were the mollusks (preparing for sowing), Homoptera (rice gleaning) and fishes (mature rice). In the biomass, the Coleoptera was also the dominant group, for mature organisms and larvae. The microhabitat with highest diversity of aquatic organisms was the green rice and the one with highest biomass is the mature rice.