Population Ecology Concepts

Population density is the number of individuals of a species per unit of area or volume at a given time, determined by biotic and abiotic factors in the environment.

The three types of population dispersion are random, clumped, and uniform. Random dispersion has individuals spaced unpredictably, clumped has individuals grouped together, and uniform has individuals evenly spaced.

The main factors are natality (birth rate) and mortality (death rate), along with immigration and emigration of individuals.

<p>Positive population growth indicates an increase in the population size (N).</p> Signup and view all the answers

<p>Negative population growth results in a decrease in population size (N).</p> Signup and view all the answers

<p>Zero population growth occurs when there is no net increase or decrease in population size (N).</p> Signup and view all the answers

<p>Every species population has the potential to expand greatly when resources are abundant.</p> Signup and view all the answers

<p>As population density increases, individuals typically access fewer resources, which can limit growth.</p> Signup and view all the answers

<p>Population ecology is the study of populations in relation to their environment, including how environmental factors influence population density, distribution, and dynamics.</p> Signup and view all the answers

<p>Birth rates, death rates, immigration, and emigration are four factors that cause changes in population size.</p> Signup and view all the answers

<p>The intrinsic rate of increase is the maximum potential growth rate of a population under ideal conditions with unlimited resources.</p> Signup and view all the answers

<p>J-shaped growth curves represent exponential growth, while S-shaped curves show logistic growth, where population size levels off as it approaches carrying capacity.</p> Signup and view all the answers

<p>Density-dependent factors are influences on population size that vary with population density, such as competition, predation, and disease.</p> Signup and view all the answers

<p>Type I survivorship curves indicate high survival rates in early and middle life stages, with most mortality occurring in older age groups.</p> Signup and view all the answers

<p>Characteristics defining a population include population density, dispersion patterns, birth and death rates, growth rates, survivorship, and age structure.</p> Signup and view all the answers

<p>Carrying capacity is the maximum number of individuals an environment can sustain without degrading the habitat, affecting population growth and stability.</p> Signup and view all the answers

<p>The primary contributor is a decrease in the death rate.</p> Signup and view all the answers

<p>The growth rate will reach zero, indicating zero population growth.</p> Signup and view all the answers

<p>Earth's carrying capacity ranges from 4 billion to 16 billion humans, influenced by living standards, resource consumption, and waste generation.</p> Signup and view all the answers

<p>Both birth and death rates declined, but the death rate declined much more significantly.</p> Signup and view all the answers

<p>The global per capita growth rate declined from a peak of 2.2% per year to 1.2% per year.</p> Signup and view all the answers

<p>It slows down population growth and may lead to a decrease in population size due to poisoning.</p> Signup and view all the answers

<p>Density independent factors are environmental factors affecting population size regardless of population density; examples include temperature and water.</p> Signup and view all the answers

<p>Temperature affects enzyme activity in organisms, influencing their distribution and overall population sizes.</p> Signup and view all the answers

<p>Light intensity influences the rate of photosynthesis in plants, which indirectly affects the number of consumers in the area.</p> Signup and view all the answers

<p>Water is essential for cellular metabolism and supports nutrient distribution; areas with good water supply can sustain more organisms.</p> Signup and view all the answers

<p>Wind can influence plant support, evaporation rates, and cause erosion, affecting the number of organisms that can thrive in those conditions.</p> Signup and view all the answers

<p>Higher oxygen levels support aerobic respiration, leading to a greater distribution of organisms that rely on oxygen.</p> Signup and view all the answers

<p>Density dependent factors are influenced by population density, while density independent factors are not and typically include abiotic conditions.</p> Signup and view all the answers

<p>Biotic potential refers to the maximum reproductive capacity of an organism under optimal environmental conditions, influencing the rate at which a population can grow.</p> Signup and view all the answers

<p>Density-dependent factors are influenced by population density, such as competition and disease, while density-independent factors affect populations regardless of their density, like natural disasters.</p> Signup and view all the answers

<p>Carrying capacity is the maximum number of individuals that an environment can sustainably support, which limits population growth when resources are scarce.</p> Signup and view all the answers

<p>Environmental resistance includes factors that limit population growth, such as lack of food, space, or adverse conditions, leading to mortality or reduced birth rates.</p> Signup and view all the answers

<p>Less developed countries are projected to experience greater population growth due to higher natality rates, while highly developed countries often have lower growth due to various socio-economic factors.</p> Signup and view all the answers

<p>Birth rate must be greater than death rate, and immigration must be greater than emigration.</p> Signup and view all the answers

<p>'r' represents the population growth rate, calculated as the birth rate minus the death rate.</p> Signup and view all the answers

<p>Biotic potential is the maximum rate at which a population can increase under ideal conditions.</p> Signup and view all the answers

<p>The age of beginning reproduction and the species' reproductive span.</p> Signup and view all the answers

<p>When natality plus immigration equals mortality plus emigration.</p> Signup and view all the answers

<p>Survivorship is calculated as the number of survivors divided by the number in the original group, multiplied by 100.</p> Signup and view all the answers

<p>Environmental resistance includes factors that limit the population's growth, such as limited resources or predation.</p> Signup and view all the answers

<p>Carrying capacity (K) is the maximum population size that an environment can sustain; population growth slows as it approaches this limit.</p> Signup and view all the answers