Wetlands are environmentally and economically important ecosystems. The irrigated rice crops are considered artificial wetlands, because they offer food and refuge to different aquatic communities. The benthic macroinvertebrates are used to study environmental quality. The knowledge from the organisms which inhabit the natural and artificial wetlands can help to verify less harmful management practices in the agroecosystems. AIM: The aim of this research was to analyze and compare the benthic macroinvertebrate community from a wetland and an experimental kind of rice cultivation. METHODS: It was used dip nets 1 mm mesh every 15 days, with six repetitions in each place, from January to March 2010. After washing and screening them in the laboratory, the organisms were identified using stereoscope microscope and identification keys, and classified according to their functional trophic group. RESULTS: The whole organisms collected were 33,293 specimens. It was found 34 taxa, being 26 founded in the rice crops and 31 on the wetland. The natural wetland shows greater abundance, being responsible for 90.47% from the total abundance in this study. In the rice crop the abundance and the richness increased in the course of collection. However, it did not reach the values founded in the wetlands during the cultivation period. The most found groups in the two environmental were Belostomatidae and Planorbidae, while Hyalellidae and Elmidae were found only in the wetland, being a stress indicator in the wetland. CONCLUSIONS: The community structure including abundance, richness and composition was statistical different between wetlands and rice cultivation.
Comparison of phospholipid fatty acid composition in percolating water, floodwater, and the plow layer soil during the rice cultivation period in a Japanese paddy field