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(Malmqvist et al. 2008). Different kinds of pollutants, pesticides, heavy metals, many non-

biodegradable objects like plastics, chemical elements – nitrogen, phosphorus, etc. are
accumulated in the nearby freshwater aquatic bodies via domestic sewage, agricultural

runoffs, industrial wastes, etc. It is observed that the run-offs are maximum when the
landscape elevation is greater and a higher amount of precipitation occurs. From the

ecological aspects, when the run-offs are higher, it is interpreted that it influences species
composition and the productivity of aquatic and wetland communities (Resh et al., 1988; Poff

et al., 1997; Meyer et al., 1999).

The primary productivity of the freshwater biome is affected more at the low latitude levels
during the highest climatic change condition. Those circumstances drive water’s

physicochemistry alteration of the aquatic body resulting in nutrient loading and acidification

of that ecosystem. Living organisms of the freshwater ecosystem, especially primary
producers (algae, macrophytes, and plants) cannot withstand a certain level of stressed

condition. . Few crucial water quality constituents are dissolved nutrients such as metals,
suspended solids, dissolved oxygen (DO), pH, etc. Physiological activities like respiration,

metabolisms, etc. are affected by both DO of the water which can alter the perseverance and
breeding the aquatic life (Hitt et al. 2015). The aquatic organisms either emphasize to survive

rather than its reproduction or migrate to any other suitable habitat. Eutrophication and

harmful algal blooms are the common issues of the freshwater ecosystem. The umbrella of
the dense algal growth on the surface water does not allow the light penetration properly and

uses the dissolved oxygen from water. It increases the biological oxygen demand, degrades
the water quality resulting in suffocation for the rest of aquatic life like fishes, invertebrates,

plants, etc. Those blooms can also release many toxic chemicals like cyanotoxin etc. into the
water. Thus, the encroachment of tolerant, invasive, and alien species has gradually shifted

the native community composition, decrease the species richness of that ecosystem.

Some particular taxa, especially those higher in the food web, are more sensitive to local
extinction along with the erratic substitution in its community (Ings et al. 2009; Woodward

2009). Those perspectives also affect the water flow regime which is an important aspect for

the survival of aquatic life. In many systems, aquatic organisms are acclimatized to the
variation in high and low water levels and specific species within the community require

drastic flow levels for survival (Poff and Ward, 1989; Poff et al., 1997). Streamflows are
regimes also a major dominant issue for this biota by controlling its availability of habitat

(e.g., seasonal floodplains) and the development of habitat types (e.g., scouring of pools and
riffles during high flows) (Hitt et al. 2015). Incidentally, it can be anticipated that species-

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