* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Ecosystems and Communities
Survey
Document related concepts
Renewable resource wikipedia , lookup
Latitudinal gradients in species diversity wikipedia , lookup
Biogeography wikipedia , lookup
Biodiversity action plan wikipedia , lookup
Habitat conservation wikipedia , lookup
Restoration ecology wikipedia , lookup
Coevolution wikipedia , lookup
Biological Dynamics of Forest Fragments Project wikipedia , lookup
Lake ecosystem wikipedia , lookup
Ecological fitting wikipedia , lookup
Natural environment wikipedia , lookup
Theoretical ecology wikipedia , lookup
Transcript
Ecosystems and Communities What is Climate? 4-1 Weather is the day-to-day condition of Earth’s atmosphere at a particular time and place Climate refers to the average, yearafter-year conditions of temperature and precipitation in a particular region. The Greenhouse Effect What is it? A natural situation in which heat is retained by a layer of greenhouse gases. What causes it? Carbon dioxide, methane, water vapor, and a few other atmospheric gases trap heat energy and maintain Earth’s temperature range. Effects of Latitude on Climate Because earth is a sphere that is tilted, solar radiation hits Earth at different angles This creates 3 main climate zones Polar zones = cold zones at the poles Tropical zones = warm zones around the equator Temperate zones = in between the polar and tropical zones, vary from hot to cold throughout the year Heat Transport in the Biosphere The unequal heating of earths surface drives winds and ocean currents spreading heat Warm air at the equator rises, cool air at the poles sinks creating wind currents Warm water at the equator rises, cool water at the poles sinks creating ocean currents 4-2 What Shapes an Ecosystem? Biotic and Abiotic Factors Niche Community Interactions Ecological Succession Biotic Factors Ecosystems are influenced by a combination of biological and physical factors. Biotic Factors are the biological (living) influences on organisms within an ecosystem. Examples: all living things it might interact with, birds, trees, mushrooms, bacteria… Abiotic Factors Abiotic Factors are the physical (nonliving) factors that shape ecosystems Examples: temperature, precipitation, humidity, wind, nutrient availability, soil type, sunlight. Together, biotic and abiotic factors determine the survival and growth of an organism and the productivity of the ecosystem in which the organism lives. The Niche A niche is the full range of physical and biological conditions in which an organism lives and the way in which the organism uses those conditions. A niche includes the type of food it eats, how it obtains it, and which other species use the organism as food. It also includes the physical conditions it requires to survive and it includes when and how it reproduces. Everything an organism does to survive! The Niche No two species can share the same niche in the same habitat. Different species can occupy niches that are very similar Example Three species of North American warblers live in the same spruce trees, but they feed at different elevations and on different parts of the trees. Community Interactions Community interactions, such as competition, predation, and various forms of symbiosis, can powerfully affect an ecosystem. Competition Competition occurs when organisms of the Resource refers to any necessity of life, same or different species attempt to use an ecological resource in the same place at the same time. such as water, nutrients, light, food, or space. The competitive exclusion principle, states that no two species can occupy the same niche in the same habitat at the same time. Predation Predation is an interaction in which one organism captures and feeds on another organism. The predator is the organism that does the killing. The prey is the food organism, the organism that is being hunted/eaten. Predation Symbiosis Symbiosis is any relationship in which two species live closely together. Symbiosis means “living together” Three main classes of symbiosis: Mutualism Commensalisms Parasitism Mutualism Mutualism is when both species benefit, they help each other. Example: many flowers depend on certain species of insects to pollinate them. The flowers provide the insects with food (nectar or pollen) and the insects help the flowers reproduce. Mutualism Commensalisms Commensalism is when one member of the association benefits and the other is neither helped nor harmed. Example: barnacles attach themselves to a whale’s skin. The barnacles don’t help or hurt the whale, but the barnacles benefit because as the whale swims, the constantly moving water carries the food the barnacles eat to them. Commensalisms Parasitism Parasitism is when one organism lives on or inside another organism and harms it. The parasite obtains all or part of its nutritional needs from the other organism, called the host Example: tape worms live in the intestine of mammals, Fleas, ticks , and lice live on the bodies of mammals, feeding on the blood and skin of the host Parasitism Ecological Succession Ecosystems are constantly changing in response to natural and human disturbances. As an ecosystem changes, older inhabitants gradually die out and new organisms move in, causing further changes in the community. These predictable changes that occurs in a community over time is called Ecological Succession. Ecological Succession Succession that occurs where no soil exists is called primary succession. When a disturbance of some kind changes an existing community without removing the soil, then secondary succession can take place. Primary Succession Stages The first species to populate the area are called pioneer species. It is usually lichens. Lichens break down rock, as they die they add organic material to help form soil in which plants can grow. After lichens, mosses appear, and grasses take root, then seedlings and shrubs can start to sprout. Lichens and Mosses (pioneer species) Succession Secondary Succession Secondary succession happens when land is cleared and plowed for farming and is abandoned or when wildfire burns woodlands.