Natural Resources & Wildlife – Principles of Ecology Introduction to Agriculture AAEC – Paradise Valley Spring 2015

What is Ecology? Ecology: scientific study of interactions among organisms & their environment. Reveals relationships between living and nonliving parts of the world Ex. Shrimp rid ocean fish of parasites

Biosphere Portion of Earth that supports life (land, sea, & air). Very diverse Supports a large amount of different animals

Abiotic Factors Nonliving parts of an organisms environment. Air currents, temperatures, moisture, light, soil Often determines types of species which survives in an area Ex. Lack of rain = drought = specific plant/area

Biotic Factors All the living organisms that inhabit an environment Competition of the same/different species Scientists investigate how biotic factors affect different species

Ecologists study interactions among organisms at several different levels.

Levels of Organization in Ecology Organism Populations Communities Ecosystems Biosphere

Definition of Terms Organism: anything living Populations: group of organisms of one species that interbreed & live in the same place at the same time. May compete for food, water or other resources How they share determines how far apart they live & how large the population becomes Some have adaptations that reduce competition Ex. Juveniles/adults different food requirements

Definition of Terms – cont. Community: is a collection of interacting populations Changes in one population will cause changes in another Ex. Hawk and mice

Definition of Terms – cont. Ecosystem: all the interactions between the biotic and abiotic factors in a certain place Habitat: the place where an organism lives out its life Niche: A role and position a species has in its environment How it meets its needs for food and shelter, how it survives and how it reproduces

3 Types of Ecosystems Aquatic 1.) Terrestrial  Land 2.) Marine  Salt Water 3.) Freshwater Aquatic

Biomes Biomes: A large group of Ecosystems that share the same type of climax community.

6 Terrestrial Biomes Tundra Temperate Forest Tropical Rain Forest Boreal (Coniferous Forest) Grassland Desert

3 Aquatic Biomes 1.) Marine = salt water 2.) Freshwater = fresh 3.) Estuary = mixture of salt and fresh

Development of Ecosystems

Succession The orderly, natural changes and species replacement that takes place in a community Occurs in stage Is often difficult to observe May take decades

Primary Succession Colonization of new site Takes a long period of time Does not “first” contain soil Ex. New Island

Secondary Succession Takes place after a natural disaster Areas previously contained life and contains soil Less time than primary Ex. Fire, Flood, or Clear Cut

Terms to Know Pioneer Species: the first plants to colonize an area

Terms to Know Climax Community: a stable or mature community

3 Types of Symbiotic Relationships Symbiosis: close relationship between 2 or more organisms Mutualism – both benefit Ex. Shark & Cleaner Fish Commensalism – one benefits the other is neither harmed or benefits Ex. Sea Snail & Hermit Crab Parasitism – One benefits and the other is harmed Ex. Dog & Heart Worms

Terms to Know Autotroph: an organism that collects energy from sunlight to produce food. Heterotroph: an organism that gets its energy by consuming other organisms

Types of Heterotrophs Herbivore: a heterotroph that eats only plants Ex. Cow, Rabbit, Grasshopper Carnivore: a heterotroph that preys on other heterotrophs Ex. Wolves, Lions Omnivore: a heterotroph that eats both plants & animals Ex. Bears, Humans Detritivores: each fragments of dead matter in an ecosystem , return nutrients to the soil, air, and water where the nutrients can be reused by organisms Ex. Worms, Aquatic Insects

Can you answer these questions? What are producers? What are consumers? What are decomposers?

Trophic Level Each step in a food chain or food web is known as a trophic level.

Food Chain Simple Model How matter & energy move through ecosystems Use arrows No more than 5 links – energy decreasing Energy lost as heat

Food Web More extensive model How matter & energy move through ecosystem Shows all the possible feeding relationships