Influence of Wastewater from Oil Refinery on Species and Biomass of Microzoon in Rootzone of Waterhyacinth
炼油废水对凤眼莲根系微型动物种类、数量和生物量的影响

There are lots of biological species in rootzone of waterhyacinth, which can purify wastewater from oil refinery. Rootzone of waterhyacinth is an ecological subsystem. There are 20 microzoon species including 13 protozoa, 3 rotifer and 4 others. The main species are Vorlicella convallaria, Rotaria rotatoria and Lepadella patella with precentages of 18.5%, 17.5% and 34.5%, respectively. The longer retention time of the wastewater is in the oxidation pond, the more species and the bigger population of microzoon in rootzone of waterhyacinth. The total biomass increases along with wastewater flow. The maximum value of the population is 1.91×107 ind /m2. There is no microzoon except Englena which is an autotrophic organism in control pond. Increase of retention time of wastewater is beneficial to biomass of microzoon and has no effect on the content of aerobic and facultative aerobic microbes in oxidation pond.