The density of a population is the number of individuals per unit area or volume: the number of oak trees per square kilometer in the Minnesota country or the number of Escherichia coli bacteria per milliliter in a test tube.

Population regulation is an area of ecology that has many practical applications. Farmers may want to reduce the abundance of insect pests or stop the growth of an invasive weedthat is spreading rapidly.

Factors affecting the size of population are , emigration, immigration, birth rate and death rate.Limiting factors—anything that limits the size of a population like certain environmental conditions, keeps a population from increasing in size and help balance an ecosystemCarrying Capacity—the maximum population size an environment can support

Calculate the density of each population. Record it in the table.

Guide Questions:1. Compare the distribution patterns of the three populations.

2. Which population has the greatest density?

3. Infer from recorded data from the possible causes for the differences in the population density.

4. What conditions could change the density of any of the population.

5. Describe how a population’s density can be used to learn about the needs and characteristics of that population.

. The Bermuda grass population is the largest then the lily population. The clover population has the least number

1. Compare the distribution patterns of the three populations.

The Bermuda grass population has the greatest density.

2. Which population has the greatest density?

availability of sunlight, nutrients, or water; presence of other organisms that feed on the plants; the space available to each individual plant

3. Infer from recorded data from the possible causes for the differences in the population density.

Any change in the factors listed in question 4 could lead to change in population density

4. What conditions could change the density of any of the population.

5. Describe how a population’s density can be used to learn about the needs and characteristics of that population.

Population density is based on the relationship between the needs of individual species and a complex mix of limiting factors. Differences might point to potential problems such as pollutants or disease.