Ecosystems and Communities Chapter 4 Ecosystems and Communities
Ch 4.1 Objectives Differentiate between weather and climate Identify the factors that influence climate
Weather vs. Climate Weather is the day to day conditions of Earth’s atmosphere Climate refers to average conditions over long periods Defined by year after year patterns of temperature and precipitation
Microclimates Areas within a region can vary in their climate Ex: southern exposure, changes in elevation, land bordering large bodies of water
Factors that Affect Climate Solar energy trapped in the biosphere Latitude Transport of heat by winds and ocean currents
Temperature Earth’s average temperature is determined by the balance of heat that stays in the biosphere and that which is reflected back to space Greenhouse gases, like CO2, cause more heat to be trapped near Earth’s surface
The Greenhouse Effect
Latitude and Solar Energy The angle at which the sun’s rays reach the Earth creates 3 distinct regions of climate: tropical, temperate and polar Seasons are created by the tilt of the Earth
Effect of Climate on Biomes
Ch 4.2 Niches and Community Interactions Define niche Describe the role competition plays in shaping communities Describe the role predation and herbivory play in shaping communities Identify the three types of symbiotic relationships in nature
Niche Organisms occupy different environments because each has a range of conditions under which it can grow and reproduce Every organism has a unique range of tolerance
stress stress Tolerance for environmental conditions helps determine an organism’s habitat- general place where an organism lives
Niche An organism’s niche describes not only what it does, but how it interacts with the biotic and abiotic parts of its environment This includes: Place in food web Environmental conditions it needs to survive Type of food it eats How it obtains food Other species that use it as food When and how it reproduces What is the niche of a bullfrog?
Niche Competitive Exclusion Principle - no two species can occupy the same niche in the same habitat at the same time Sharing a niche results in competition in nature often results in winner and loser – losing organism fails to survive Different species can occupy similar niches. Resource partitioning helps organisms with similar niches avoid competition
Warbler Niches Cape May Warbler Feeds at the tips of branches Bay-Breasted Warbler Feeds in the middle part of the tree Cape May Warbler Feeds at the tips of branches near the top of the tree Spruce tree Yellow-Rumped Warbler Feeds at the lower parts of the tree and bases of middle branches
Community Interactions Competition- same or different species attempt to use an ecological resource in the same place at the same time
Community Interactions Predation - one organism captures and feeds on another organism Predator – the one killing and eating Prey – the food
Community Interactions-Symbiosis Symbiosis- an interaction between two species living close together Three types: Parasitism – one is harmed (host), one benefits (parasite) Mutualism – both benefit Commensalism – one is neutral, one benefits
Mutualism Parasitism Commensalism