Biotic factors comprises of living entities, in the ecosystem, whereas abiotic factors constitute the non-living organism that have an impact on the living entities. When an area in an ecosystem is not used, other organisms will reside in that habitat, thrive and reproduce according to the environmental condition.

These conditions are known as the abiotic factors. When there are various forms of organism in the environment, the actions of one species, will have an impact on the other organism. This is known as biotic factors. The major component of the freshwater ecosystem is the sun, which is source of light to plants, which are the producers.

However, light can be affected by various factors and the amount of time these ecosystem receive light vary and even its intensity. The factors are:

a) Altitude: There is seen a fall in the temperature, for sea level more than thousand meters. Height will also have impact on the amount of light reaching the ecosystem. Thus, determining which organism will reside.

b) Location: The amount of sunlight the equator gets is around 12 hours and the remaining hours, its dark. The latitudes obtains sunlight for 6 months and the remaining months are dark. Thus, having an effect on which organism will reside due to the variations.

c) Season: There are 4 types of season which exist; however, these seasons differ as the amount of light and heat is more in summer and less in winter. Thus, depending on which organism can tolerate varying climatic conditions.

d) Cloud Cover: this is a very important factor, as it will impact the amount of time where sunlight reaches the ecosystem and the duration as well. As organism require sunlight to prepare their food, through photosynthesis, sunlight is very vital to them.

e) Aspect: The amount of light which hits the water surface, is the angle of incidence. When the sun is up in the sky, more amount of light is absorbed by the water, directly, however, during the night time absorption occurs very little. Thus, depending on the sun and the time, aspect will vary.

Thus, these are the abiotic factors which will decide which organism will thrive and survive in the freshwater ecosystem. Along with which is used by organism for photosynthesis, it also provides temperature at which organisms survive. Thus, temperature plays a major role on the ecosystem and the organism thriving.

Aquatic organisms are thus called as ectotherms, as their body temperature is regulated as per the environment temperature. However, temperature has as impact on the density. If there is change in water density, which means animals in the freshwater environment will pertain less resistance.