Preview

population ecology

Powerful Essays
Open Document
Open Document
2211 Words
Grammar
Grammar
Plagiarism
Plagiarism
Writing
Writing
Score
Score
population ecology
:

13.0 POPULATION ECOLOGY
(2 HOURS)

Learning outcomes :
13.1 Population Growth
(a) Explain biotic potential (r) and environmental resistance and their effect on population growth
(b) Explain carrying capacity and its importance (c) Describe natality and mortality and their effects on the rate of population growth Learning outcomes :
13.1 Population Growth
(d) Explain population growth curves
(state the basic forms of growth curves) i. Exponential growth curve (human) ii. Logistic growth curve (Paramecium sp.)
(e) Explain the limiting factors affecting the population size :
i. Density dependent factors ii. Density independent factors

Population Ecology
• The study of variables
• That determine the population density and distributions
• Of a population in time and space

Learning Outcomes :
13.1 (a): Explain biotic potential (r) and environmental resistance and their effects on population growth

Biotic Potential (r) :

The number of offspring of an individual organism that would survive to reproductive age under ideal condition Learning Outcomes :
13.1 (a): Explain biotic potential (r) and environmental resistance and their effects on population growth

FIGURE 1

Learning Outcomes :
13.1 (a): Explain biotic potential (r) and environmental resistance and their effects on population growth

Biotic Potential is influenced by :

1. The age beginning of reproduction
2. How often reproduction occurs
3. How many offspring are born at a time

Learning Outcomes :
13.1 (a): Explain biotic potential (r) and environmental resistance and their effects on population growth

Biotic Potential & its Effect on Population
Growth
• Biotic potential (r) also varies according to the age structure of a population
• It also may influence by male : female ratios
• When conditions are optimal and there are no limitations, a population can grow at its maximum biotic potential (the vital index, rmax)
• However,

You May Also Find These Documents Helpful

  • Good Essays

    Pt1420 Unit 6 Lab Report

    • 1184 Words
    • 5 Pages

    In this exercise we will examine the effects of different kinds of potential evolutionary factors on the genetic makeup of simple, model populations.…

    • 1184 Words
    • 5 Pages
    Good Essays
  • Satisfactory Essays

    Bio 303 Study Guide

    • 1482 Words
    • 6 Pages

    d.) Change in the abundance of a mutualist 54.) b in the above equation describes a.) The competitive effects of species 2 on species 1 b.) The birth rate of a prey species c.)…

    • 1482 Words
    • 6 Pages
    Satisfactory Essays
  • Good Essays

    unit 4222-265

    • 923 Words
    • 4 Pages

    Every species has a great ability to produce offspring and its population expands until it runs out of food or it is limited by competition, its own waste products, or some other factor. Changes in climate or introduction of a new species from elsewhere can greatly affect the balance of nature.…

    • 923 Words
    • 4 Pages
    Good Essays
  • Good Essays

    Biol 101 Hw1

    • 1049 Words
    • 5 Pages

    Human activities threaten the biosphere by overpopulation and releasing chemicals into the air that interfere with natural processes and destroy other species' populations.…

    • 1049 Words
    • 5 Pages
    Good Essays
  • Good Essays

    · Identify and discuss the effects that a growing human population may have on that ecosystem’s resources, including loss or harm to populations of wild species.…

    • 471 Words
    • 3 Pages
    Good Essays
  • Satisfactory Essays

    Bio 116 Hw Asssignment

    • 752 Words
    • 4 Pages

    2. Why has the human population continued to grow in spite of environmental limitations? Do you think this growth is sustainable?…

    • 752 Words
    • 4 Pages
    Satisfactory Essays
  • Powerful Essays

    Apes Ch 9 Outline

    • 1366 Words
    • 6 Pages

    * Carrying capacity is determined by biotic potential and environmental resistance. This is the number of a species’ individuals that can be sustained indefinitely in a specific space.…

    • 1366 Words
    • 6 Pages
    Powerful Essays
  • Satisfactory Essays

    St. Lucia Fact Sheet

    • 288 Words
    • 2 Pages

    8. How does each of the following environmental resistance factors affect the people of your assigned country?…

    • 288 Words
    • 2 Pages
    Satisfactory Essays
  • Satisfactory Essays

    Envor Cod Paper 1

    • 319 Words
    • 2 Pages

    6. What connection or relationship between biodiversity and P/R can be made with this information? (10 pts)…

    • 319 Words
    • 2 Pages
    Satisfactory Essays
  • Good Essays

    Organisms with Exponential (r) reproductive strategies (bacteria, fungi, and many insects) tend to produce a large number of offspring, tend to have a shorter lifespans, show little or no care for their offspring, and tend to be smaller organisms that mature faster. This reproductive strategy affects the population size over time by having a drastic increase in population until it reaches the carrying capacity of the environment leading to decline and the population due to the lack of resources. Organisms with Logistic (K) reproductive strategies (Bears, Whales, and humans) tend to have fever reproductive events, tend to have longer life expectancy, have more care for their offspring, and have fewer offspring. This affects population growth by having an exponential growth phase but eventually decelerating into a stable equilibrium where the number of deaths and the number of birth are about equal, this allows the population to stay under the carrying capacity of the environment to avoid a drastic decline in…

    • 533 Words
    • 3 Pages
    Good Essays
  • Good Essays

    Ecology Life History

    • 3009 Words
    • 13 Pages

    What is the connection between age at first reproduction and lifespan? Is there a general pattern?…

    • 3009 Words
    • 13 Pages
    Good Essays
  • Powerful Essays

    There are a number of factors that can contribute to the growth of a population and these trends can be seen in a number of species. It is generally believed, from an ecological perspective, that populations will display either an exponential of logistic growth rate. If optimal environments are consistently maintained with no biotic or abiotic limiting factors (excess food, excess space availability, optimum climactic environment, no predation, etc) then a population will grow in an exponential direction. Species with high maximal relative growth rates do not occupy infertile habitats because their physiologies are more sensitive to suboptimal habitats and so their relative growth rates decrease more rapidly as fertility of the environment decreases (Shipley, 1988). A logistic curve will occur in population growth if the population is exposed to at least one limiting factor. The logistics model is and empirical description of how a population tends to grow when environmental conditions are not optimal. Although these two models can be seen in some species of organisms such as bacteria, they are rarely exhibited in natural occurring populations in the wild. In nature population growth in organisms is seen as more or less regular oscillations with high and low points, termed, the time lag model. In the time lag model there is a lag between a change in the environment and a corresponding change in the rate of population growth. These cyclic oscillations are influenced by the environment which the organism inhabits. Changes in the environment can affect numerous functions of an organism including natality (amount of births in a population) and mortality (number of deaths in a population). Laboratory populations of Daphnia are a good example of the effect of time lags on population growth (BOOK)!!!!!!. In this experiment Daphnia magna were utilized to observe the direct relationship of one limiting factor (food in this case) on the dynamics of…

    • 1966 Words
    • 8 Pages
    Powerful Essays
  • Satisfactory Essays

    References: Harich, J., Bangerter, P., & Durlacher, S. (2012). Solving the Sustainability Problem with Root Cause...…

    • 334 Words
    • 2 Pages
    Satisfactory Essays
  • Good Essays

    The second chapter provides a theoretical picture of how demographic growth takes place. According to the author, this growth is determined by two systems of forces: constraint and choice. The forces of constraint are those that impose limits to demographic growth such as climate, disease, land, energy, food and space. These forces are interrelated between them and change very…

    • 1002 Words
    • 5 Pages
    Good Essays
  • Good Essays

    Maths in Every Day Life

    • 472 Words
    • 2 Pages

    tive if there existed a decline in population. Otherwise, r can be found as a ratio of the birth rate to the death rate. If we let 1 + r = b, the base of the exponential expression, the function becomes p = p 0bt. An alternative version of this relation describes the time it would take for the population to reach a given amount p: t = logb( p / p0). Students will use both functions to predict the future global population, provided the current growth rate or 1.3% (Abbott, 2004). This relation will also be used to find out how long it will take the global population to reach a certain level.…

    • 472 Words
    • 2 Pages
    Good Essays