Module 3 Environmental Science

It refers to the group of individuals of the same species inhabiting the same area. It is characterized by the total number of individuals and the space they occupy per unit area.

It is the precise number of individuals in an area. It may have a large or small number of individuals that are distributed densely or sparingly in a local area

It is used to make inferences about the population as a whole.

Two methods are use:

For immobile or slow-moving organisms like plants. It is a square structure that must be placed at random locations within the habitat enough times and count the number of individuals within its boundaries.

For smaller mobile organisms such as mammals. a method in which animals are captured, marked, and released back into the environment to mix with the rest of the population. Later, a new sample is captured and counts how many of these marked animals are in the new sample.

It indicates how crowded a population is. It is a measurement of population per unit area or unit volume

It is the distribution of the individuals throughout their range in an area.Individuals within a population can be distributed into different patterns

It occurs when individuals aggregate in patches like wolf pack attack prey, mushroom on a rotting log, and so on

It occurs when individuals are evenly distributed and usually seen in territorial animal species like penguins that maintain a defined territory for nesting.

It is a unique pattern where each individual's position is independent of other individuals—for example, plants established by windblown seeds in the forest.

births of new individuals (natality rate).

permanent arrival of new individuals into the population

deaths of individuals (mortality rate)

movement of individuals out of a population

It describes populations that increase in numbers without any limits to their resources or encounter some other limitation. The important concept of this growth rate model is that the population size is increasing at a greater rate. When the population size, N, is plotted over time, it forms a J-shaped growth curve.

It is a more realistic model of population growth in which it introduces limits to reproductive Growth. As the population size increases, resources will be depleted, and the growth rate will slow down due to limited resources. Populations do not exist in isolation and share the environment with other species, competing with them for the same resources.

The maximum population size that a particular environment can sustain is called

o This Growth is not dependent on the density of the population. The population increases at a rate determined by its biotic potential. Many factors influence the death rate regardless of its density and may only be slowed down by severe environmental catastrophes such as drought, storm, earthquakes, and the like. As a result, it reduces the population regardless of population size.

o This is a growth influenced by the density of the population. As the density of the population increases, the resources become limited. Thus, it affects the availability of specific resources to other species and can influence population size further. Examples of this are food supply, nesting sites, mating partners, and so on

It is the statistical analysis of the human population, which encompasses the size, distribution, structure, and changes in the population that occur over time.

It is the proportion of people by age, sex, ethnicity, education, and other parameters.

It refers to the actual production of offspring. It depends on various factors like physical health and nutrition, sexual behavior, culture, emotions, economics, way of life, etc. Thus, fertility rates vary among countries and cultures.

It is a measure of the number of deaths in a particular population depending on various factors like age and gender distribution.

It refers to the average survival time for an individual.

It is the physical movement of people from one place to another. It is divided into two groups of factors: push and pull.

The push factors are things that an immigrant is unfavorable about the area he is coming from, while pull factorsinterest the immigrant in the new place

These are important data from sources like statistics registries (Phillipine Statistics Office/PSA) and censuses. Statistics registries track all status on births, deaths, marriages, migrations, and the like. The national government usually conducts censuses. Its main goal is to count every person in the country and collect information on such variables as age, sex, marital status, education, employment status, and occupation.

It is a population parameter that refers to the number of individuals of each sex and age group and is often represented by a bar graph called a population pyramid.

It refers to the rate of males to females in a population

It is a statistical tool that summarizes the number of deaths of a population. It yields information about longevity and gives a reasonable estimate of life expectancy.

Population Ecology

Population Density

Population Size

Population Distribution

Population Growth

Carrying Capacity

Natality

Mortality

Immigration

Emigration

Quadrat Sampling

Mark-Recapture Sampling

Clumped Distribution

Uniform Distribution

Random Distribution

Exponential Growth

Logistic Growth

Density-Dependent Factors

Density-Independent Factors

Demography

Population Structure

Fertility Rate

Mortality Rate

Life Expectancy

Migration

Push Factors

Pull Factors

Statistics Registries

Censuses

Population Pyramid

Sex Ratio

Life Table