Principles of Ecology and Microbial Ecology Lecture Topic

Principles of Ecology and Microbial Ecology Lecture Topic Number 1 ENVH 4387/5387 Biological Analysis ENVH 4387/5387 1

Reading Assignment " Prescott Chapter 40 ENVH 4387/5387 2

Introduction " Ecology - That branch of biology that deals with the interrelationships between living organisms or the interaction between organisms and the abiotic environment " We will learn about the interaction between pollutants, the environment, people, and the role microorganisms play in these interactions ENVH 4387/5387 3

Overview l l The environment must be able to assimilate human wastes Overloading of wastes in the environment results in » » » l Human health effects (disease) Loss of ability to produce food Loss of usable water Loss of suitable living space Loss of suitable recreational space The ability of the environment to assimilate human waste is mediated by the biological, chemical, and physical components of the environment ENVH 4387/5387 4

Vocabulary " Environment A All of an individual organism’s surroundings, both the inanimate components (air, soil, water) and other plants and animals. Abiotic - The nonliving component of the environment " Biotic - The living component of the environment " Biosphere - the portion of earth that is inhabited by living organisms. " ENVH 4387/5387 5

Vocabulary l The abiotic component of the biosphere includes » inorganic compounds » climate ENVH 4387/5387 6

Vocabulary l The biotic component can be divided into » Primary producers - photosynthetic organisms, i. e. algae, green plants, and photosynthetic bacteria » Consumers – All living organisms other than the primary producers i. e. herbivores and carnivores – Ultimately depend on the primary producers for energy ENVH 4387/5387 7

Vocabulary l Species » Groups of interbreeding natural populations that are reproductively isolated from other such groups l Population » Group of organisms belonging to one species that occur within a defined area. l Community » the populations of different species that exist in the same defined area (groups of populations living together as an association). ENVH 4387/5387 8

Vocabulary l Habitat » Inanimate or abiotic components for individual, population, and community l Ecosystem » Habitat plus community l Trophic level » The level of an organism in a community based on its feeding requirements (e. g. , producers are at the lowest trophic level) ENVH 4387/5387 9

Vocabulary l Succession » Continuous replacement in time of one community by another community. » These changes in communities are controlled by both the dynamic nature of the abiotic and biotic components of the ecosystem ENVH 4387/5387 10

Vocabulary l Climax community » The mature stable community developed after many stages of ecological development. » When the population reaches equilibrium and the communities stop changing, the system has reached a climax (activated sludge) » some ecosystems never reach a climax ENVH 4387/5387 11

Vocabulary l Energy Transfer » Organisms utilize solar radiation and a pool of chemicals as their prime source of energy (Primary producers) » This energy is transferred from one organism to another (from one trophic level to another) » This is the basis of the nutrient cycles that we will discuss later in the semester ENVH 4387/5387 12

Vocabulary l Food Chain or Food Web » The sequence of organisms that feed on each other, starting at the phytoplankton and leading to very large organisms » Energy is transferred through the biosphere in food chains or food webs » The sequence of trophic levels in an ecosystem ENVH 4387/5387 13

Vocabulary l Biomagnification » An important attribute of food chains is their ability to concentrate nonmetabolizable toxic materials » Materials that are present in extremely low concentrations in the abiotic phase can be concentrated in a stepwise manner until at the higher trophic levels they may upset essential metabolic processes » The large numbers of individuals consumed to maintain the next trophic level magnifies the concentration of toxic material per unit body weight ENVH 4387/5387 14

Vocabulary l Biomagnification » The ecological danger of biomagnification is amplified by the concentration of toxic materials in specific organs and tissues » e. g. DDT ======> in eggs » Pesticides =======> fish, liver, & fatty tissues ENVH 4387/5387 15

Vocabulary l Homeostasis » The buffering capacity of an ecosystem that allows the ecosystem to resist perturbations l Positive feedback » when part of the output is returned to the original input l Negative feedback » when materials are taken out of the system ENVH 4387/5387 16

Vocabulary l Pollutant » a substance that occurs in the environment at least in part as a result of human activities, and which has a deleterious effect on living organisms l Contaminant » a substance released by human activities, does not have a deleterious effect ENVH 4387/5387 17

Next - Population Dynamics l l Effect of pollutants on population size Influenced greatly by many factors ENVH 4387/5387 18