The invention provides a direct-viewing, accurate and practical combined application method of '
water body sampling, bionidicator, water
environmental simulation and
watershed health diagnosis' for diagnosing health of a
watershed ecology system aiming at the problem that
watershed pollution affects the health of the
ecology system and dominant species and pollutants are different in different watershed
biology systems. The method comprises the following steps of: firstly, rating the dominant species of the watershed
biology system, and analyzing types of key pollutants of the watershed so as to select a biological indicator; secondly, designing a
water environment simulation area according to the similarity law; thirdly, determining a watershed sampling point, setting a
water intake so as to introduce watershed
water body into the
water environment simulation area, and planting and / or breeding the biological indicator in the
water environment simulation area; and finally, draining the
wastewater in the simulation area into the watershed
water body by using a discharging system. By adopting the method, the health of the watershed
biology system is determined by observing the
health condition of the biological indicator in the simulation area, and the method has high scientificity and practicality, is suitable for
health diagnosis of the watershed biology systems which are in different scales and contain different pollutants, and has the advantages of direct viewing and accurate determination.