*Monitoring of Rivers and Streams Conditions Using Biological Indices with Emphasis on Algae… DOI: http://dx.doi.org/10.5772/intechopen.105749*

and is amenable to prediction techniques [50]. In the U.K., it was used for the period 1994–1997 for quality assessment [51], for the determination of characteristics and controls of Gravel-Bed Riffles [52], for the classification of urban rivers [53], and for the aims of the WFD hydro-morphological assessment (STAR Project overview) [54]. Also, in exploring the interactions between flood defense maintenance works and river habitats [55], for environmental assessment and catchment planning [56] and for the evaluation of the effects of riparian restoration [57]. In Serbia, it was used in the Golijska Moravica and Jerma basins [58], in Austria for the identification of rivers with high-and-good habitat quality [59], in Germany for river habitat monitoring and assessment [60], in the U.S. for the measurement of Little Tallahatchie River in northern Mississippi [61], and in Portugal for fluvial hydromorphological assessment [62]. Also, in Poland regarding its seasonal diversification [63] and in Southern Europe [64].

River geomorphology is a characteristic often used for river health evaluation as seen [7] and is deemed to be quite important [65]. Geomorphology impacts water quality [66], and its assessment is used in place of "command-and-control" practices that cause environmental damaging biodiversity reduction and lessening provision of ecosystem services [67], and its change is associated with river rehabilitation [68] while *via* the River Styles framework links policy with action-on-the-ground. Also, along with ecology and river channel, habitats constitute a mesoscale approach to basin-scale challenges [69], assist in determining the ecological health of wadable streams [70], and affect riparian habitat within alluvial channel-floodplain river systems [71], and its spatial variability impacts the disturbance temporal patterns influencing ecosystem structure/dynamics [72], acting as a framework for the analysis of microplastics in riverine sediments [73].

The Index of Stream Condition (ISC) was developed, tested, and applied in Australian regions [5], for example, in Victoria [74] as seen in **Figure 2**.

The basis of the ISC system lies in a subjective ranking system whereby the current condition of a river is compared to a known/modeled "pristine" condition across the index/subindex groups seen in **Figure 1** which are scaled to (0–10) values and added as seen in **Figure 3**.

It should be noted that macro-benthos data are included [5, 7].


### **Figure 2.**

*Third benchmark index of stream condition subindices and metrics of hydrology [75].*

**Figure 3.**

*North east region: (a) index of stream condition, (b) upper Murray index of stream condition, (c) part of the upper Murray calculation \* [76]. \*insufficient data are not added.*
