Transcript Chapter 4x
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 near the top of the tree Bay-Breasted Warbler Feeds in the middle part 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 InteractionsSymbiosis • 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