Abstract:

Ecosystem health was a newly proposed concept in the world with the environment becoming a serious issue. A method, trophic state-comprehensive index based on researches on the ponds ecosystem health had been proposed to assess the ecosystem health of 3 kinds of ponds under different water purification methods, the conventional water self-purification, using of immobilized bio-film structure of artificial substrates, and the using of floating bed vegetation (the Ipomoea aquatica). Firstly, 4 indices including Chla, SD, TP and TN were chosen to calculate the trophic status index (TSI). Secondly, nondimensionalizated indicators such as physical indicators, chemical indicators and biological indicators were used to calculate comprehensive index to estimate the ecosystem health state. The result showed that under the 2 water purification methods, the TSI of the intensive ponds decreased, and the CI of the intensive ponds increased, which meant that the 2 water purification methods can make the ecosystem health of the intensive ponds much better. Most importantly, the results also reflected the fact that the combination of TSI and CI can be the method of assessing the ecosystem health of intensive ponds and even all trophic-level ponds.