Investigate the Factors Effecting the Distribution of Living Organisms in Freshwater Ponds
Hypothesis
My aim is to investigate the factors effecting the distribution of living organisms in freshwater ponds. I think the abiotic factors, which will effect this, will be:
- Temperature
- pH levels (% of hydrogen ions)
- Light intensity
- Conductivity
- Chemicals from acid rain
- Fertiliser (pollutants)
- Oxygen levels
- Carbon dioxide levels
- Space and shelter
I think the biotic factors, which will effect the distribution of living organisms, will be:
- Influence of people
- Predators
- Prey
- 'Food' availability
- Plants - producers
- Competitions between organism for example food, space and 'mates'. Either intra specific competition or inter specific competition. Intra-specific competition occurs when two or more individuals of the same species strive to obtain the same resources, which are of limited supply. Inter-specific competition is the same as intra-specific but the conflicts are of different species.
Although all the abiotic and biotic factors would effect the distribution of living organisms, I think the 3 main factors, which will effect the distribution the most are:
- Conductivity
- Oxygen levels
- Light intensity
This is because the brackish water in the freshwater pond probably contains the most common sea salt, sodium chloride, which is also known as common table salt. To measure the salinity of the water we can conduct electricity through the water and measure its conductivity. Sea salts are called electrolytes because, when dissolved, their charged ions enhance the ability of water to conduct electricity. So if there were a high level of ions in the water then the conductivity reading would also be high because of the extra ions conducting the extra electricity. Now by using a submerged electrode to measure conductivity we can produce quick and accurate results. Conductivity id measured in parts per 1000. The dissolved ions are need for the plants health, if it does not get the sufficient amounts of minerals and nutrients this will cause deficiency symptoms. If the mineral content were low then the plant would become unhealthy because it is not functioning correctly and therefore could not produce glucose and oxygen.
