The body of water experiences eutrophication.
The process of eutrophication takes place primarily in ecosystems with gradual changing waters, mainly in deep lakes. In the depths of the lake, where deposition of dead algae takes place, the aerobic bacteria, which feeds on them proliferate that in turn consumes more amount of oxygen.
Though in the absence of enough circulation of water that is usually found in the case of deep lakes, the bottom of the lake is poorly oxygenated and the bacteria eventually deplete the oxygen found in the deep layers of water. Thus, they can no longer degrade all the dead organic matter and gets accumulated in the sediments. The lake is now considered to be aging.
Answer:
Length of the cells = diameter of field of view/ number of cells across the field of view
Explanation:
therefore 2.25= 4.5*X
X= 2.25/4.5
=0.5 number of cells
The correct answer is - 1) inverted pyramid, with a narrow base representing a small number of young individuals.
The populations that are decreasing are usually population in countries that are highly developed. The conditions for living are excellent, the medical care on high level, life expectancy very high, but the birth rates very low.
In this type of conditions, there's smaller and smaller number of young individuals, with the middle aged population being much bigger, and the older population being constantly on the rise. This will give the age-structure histogram a reverse shape than what it is supposed to have, it will be similar in appearance like a inverted pyramid, meaning that the population is aging and that it will be constantly on a decline in the future.
Answer:
The simultaneous effect of a predator population on a prey population and a prey population on a predator population over time.
Explanation:
The mathematical models of Lotka-Volterra equations explain the existing interaction between species in which prey and predator influence and affect each other. The model follows a few assumptions,
- The ecosystem is isolated and closed. There is no migration.
- The whole individuals are reproductively equivalent.
- In the absence of the predator, prey shows an exponential growth rate. The prey is in the ideal environment.
- When there is no prey, the predator population decreases exponentially because of the lack of food. The predator environment is ideal, but it is limited by prey density.
- The predation rate is proportional to the encounters rate, which also depends on density.
- The predators affect the prey populations, inducing its decrease proportionally to the number of prey and predators present.
- The prey population also influences the predator population proportionally to the number of encounters between the two species.
In these equations, the variable D is the number of predators, and P the number of prey items.
The parameters are always constant:
• r1: prey growth rate.
• a1: predator hunting success.
• r2: predator growth rate.
• a2: the success of the predator in hunting and feeding.
In nature, many factors affect interactions, such as dense-dependent factors and dense-independent factors. Also, in reality, there are stochastic factors. Stochasticity refers to the variability in the system involving those factors that are affecting or influencing population growth. Stochasticity might be related to good years and bad years for population growth.
In real situations, the compliance of the whole assumption does not occur. The previously mentioned constants might vary, constantly changing the interaction between the predator and the prey. These parameters change in different degrees, resulting in varying circumstances for both species.
