166
D. Absalon et al.
research. In Fig. 7.19 examples of daily measurement results of selected parameters
are presented. They show how important it is to implement continuous measurements
of relatively changeable parameters into “classic” monitoring.
Chlorophyll (a) concentration in water is an important index of water quality and
algal bloom threat, at the same time carrying information about primary biomass
production and food abundance for consumers in the reservoir. This index is dependent on oxygen and carbon dioxide concentration, pH, water temperature, insolation,
and turbidity, as well as concentrations of biologically available forms of nitrogen
and phosphorus. Chlorophyll (a) concentration is also a function of phytoplankton
count. Determination of chlorophyll by counting plankton specimens is troublesome
and time-consuming, moreover, at the stage of condensation of tests, it is possible
to lose the smallest nanoplankton forms. Classical monitoring with laboratory determination of chlorophyll is equally labour-consuming. Metagenomic methods that
reveal semi-quantitatively the presence of ribosomal DNA from chloroplasts of the
main groups have similar limitations as manual monitoring, and also require creating
databases and calibration. These limitations do not apply to the monitoring with the
use of automatic sondes detecting chlorophyll with the fluorescent method. Currently,
fluorescent methods enable in situ measurements of photosynthetic dyes characteristic of 4–5 different taxonomic phytoplankton groups (cyanobacteria, chlorophytes,
diatoms with dinoflagellates and chrysophytes, cryptophytes) [46, 47]. Continuous
monitoring makes it possible to observe diel vertical migration of phytoplankton and
correlation of oxygen concentration and pH [48–50].
Although continuous monitoring is not yet so perfect for, excluding the necessity of measurements with traditional methods and expensive laboratory analyses,
it shows the direction where modern water quality testing methodology is heading.
Measurements with the use of automatic sondes, besides constant access to results—
to a great extent independent of weather, season, time of day, or meteorological
conditions—point to new possibilities of monitoring water quality [51]. Continuous
monitoring of physical and chemical parameters of water shows the dynamics of
the observed indexes, not only seasonal changes but also daily fluctuations. This
improves the possibilities of the proper interpretation of the obtained values and the
speed of reaction to threats.
7.7 Conclusions
Pursuant to the Water Framework Directive, dam reservoirs are treated as heavily
modified water bodies, so they are required to achieve at least good ecological status
by year 2021. Reservoirs, which are considered to be heavily modified sections of
rivers, are mostly not very similar to rivers.
The analysis of water quality of 22 selected dam reservoirs showed the follow-ing
regularities:
D. Absalon et al.
research. In Fig. 7.19 examples of daily measurement results of selected parameters
are presented. They show how important it is to implement continuous measurements
of relatively changeable parameters into “classic” monitoring.
Chlorophyll (a) concentration in water is an important index of water quality and
algal bloom threat, at the same time carrying information about primary biomass
production and food abundance for consumers in the reservoir. This index is dependent on oxygen and carbon dioxide concentration, pH, water temperature, insolation,
and turbidity, as well as concentrations of biologically available forms of nitrogen
and phosphorus. Chlorophyll (a) concentration is also a function of phytoplankton
count. Determination of chlorophyll by counting plankton specimens is troublesome
and time-consuming, moreover, at the stage of condensation of tests, it is possible
to lose the smallest nanoplankton forms. Classical monitoring with laboratory determination of chlorophyll is equally labour-consuming. Metagenomic methods that
reveal semi-quantitatively the presence of ribosomal DNA from chloroplasts of the
main groups have similar limitations as manual monitoring, and also require creating
databases and calibration. These limitations do not apply to the monitoring with the
use of automatic sondes detecting chlorophyll with the fluorescent method. Currently,
fluorescent methods enable in situ measurements of photosynthetic dyes characteristic of 4–5 different taxonomic phytoplankton groups (cyanobacteria, chlorophytes,
diatoms with dinoflagellates and chrysophytes, cryptophytes) [46, 47]. Continuous
monitoring makes it possible to observe diel vertical migration of phytoplankton and
correlation of oxygen concentration and pH [48–50].
Although continuous monitoring is not yet so perfect for, excluding the necessity of measurements with traditional methods and expensive laboratory analyses,
it shows the direction where modern water quality testing methodology is heading.
Measurements with the use of automatic sondes, besides constant access to results—
to a great extent independent of weather, season, time of day, or meteorological
conditions—point to new possibilities of monitoring water quality [51]. Continuous
monitoring of physical and chemical parameters of water shows the dynamics of
the observed indexes, not only seasonal changes but also daily fluctuations. This
improves the possibilities of the proper interpretation of the obtained values and the
speed of reaction to threats.
7.7 Conclusions
Pursuant to the Water Framework Directive, dam reservoirs are treated as heavily
modified water bodies, so they are required to achieve at least good ecological status
by year 2021. Reservoirs, which are considered to be heavily modified sections of
rivers, are mostly not very similar to rivers.
The analysis of water quality of 22 selected dam reservoirs showed the follow-ing
regularities: