Water Quality Indices (WQI) - Water Quality Management: Assessment and Interpretation - page 22

Doylido et al. ( 1994 ) studied water quality index in the Vistula river basin in
Poland. Bocci et al. ( 1994 ) investigated Marine bacteria as indicators of water
quality. They also developed a water quality index during the course of their
research. Erondu et al. (1993) studied the classi

cation of the new Calaba River at
Aluu Port Harcourt in Nigeria using an experimental model. The primary indicators
of water quality were BOD, Dissolved Oxygen (DO), temperature, sul de and other

physic-chemical and biological parameters. Jonnalagadda and Mhere ( 2001 ) stud-
ied the water quality of Odzi River, the main river issuing forth from the Eastern
Highlands of Zimbabwe, using water quality indices. They monitored chemical
parameters namely temperature, conductivity, total suspended solid, BOD, total
phosphate and nitrate for 6 months sampling stations during 9 months. The results
indicated that while the water was medium to good quality in the upper stream, the
quality vitiated downstream, possibly due to the seepage from the abandoned mine
dumps and discharges from farm land which in

ltrated the river. Vollenweider et al.
( 1998 ) developed a new trophic index (TRIX) based on chlorophyll, oxygen sat-
uration, mineral and Total Nitrogen (TN) and phosphorus, which is applicable to
coastal marine water. The index is scaled from 0 to 10 covering a wide range of
trophic conditions from oligotrophy to eutrophy. Secchi disk transparency com-
bined with chlorophyll; instead, de ne a turbidity index (TRBIX) that serves as a

complementary water quality index. The two indices are combined in a General
Water Quality Index (GWQI). Ladson et al. ( 1999 ) developed an index of stream
conditions (ISC) to assist water management by providing an integrated measure of
their environmental condition. The ISC scores five aspects of the stream conditions:

Hydrology: evaluated by tabulating changes in volume and seasonality of the

￿

flow from the natural condition

Physical form: assessed by the bank stability, bed erosion or aggregations,
in

￿

cial barriers, as well as the abundance and the origin of the
coarse woody debris

uence of arti

Stream side zone: based on the types of plants, spatial extent, width and
intactness of the riparian vegetation, regeneration of over story species, and the
condition of wetlands and billabongs

￿

Water quality: based on an assessment of phosphors, turbidity, electrical con-
ductivity and pH

￿

Aquatic life: appraised by the number of macro invertebrate families present.

￿

ciency of 12 ecological indices
expressing diversity, abundance, evenness, dominance and the biomass of phyto-
plankton to describe the tropic levels in the coastal area in the Eastern Mediterra-
nean. They found that some of the commonly used indices such as the Simpsons

Karydis and Tsritisis ( 1996 ) assessed the ef

'
Shannon and Mayalef indices did not perform quite satisfactorily when used to
establish eutrophic trends. On the other hand, the Menhinick

s
index, Species Evenness, Species Number and Total Number of individuals proved
effective for distinction among oligotrophic, mesotrophic and eutrophic waters. The
most ef

' s index, Kothe '

cient among this lot; however, was the Kothe sand species number indices.
Bordalo et al. ( 2001 ) studied the water quality of the Bangpakong River, the most