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What do terms like biosphere, ecosystem, population, and ecology make you think of? Work with 3-4 partners and write down your ideas. http://teachers.saschina.org/dbister/files/2010/11/Biology_Biosphere1.jpg Name biotic and abiotic factors in this ecosystem. Describe some interactions between the biotic and abiotic factors. AGAIN - Name biotic and abiotic factors in this ecosystem. Describe some interactions between the biotic and abiotic factors. A habitat is a specific set of biotic and abiotic characteristics in which individuals of a species can thrive. An ecological niche which is the task an organism plays in the habitat. A beaver lives in a forest habitat A beaver’s niche is to be a consumer of trees and to modify the habitat to convert rivers to ponds for other organisms. A model that describes the feeding relationship between a predator and a single line of consumers Organisms get their energy by eating other organisms Large geographic areas that are similar in climate and have similar types of plants and animals. The living parts of an ecosystem How carbon moves through Earth’s atmosphere and its ecosystems An organism that captures energy and stores it in food as chemical energy The scientific study of how organisms interact with their environment and other organism The movement of water through the environment The word used to describe a particular environment and all the living things that are supported by it. A series of events that happen over and over again The nonliving parts of an ecosystem Model of feeding relationship between many different consumers and producers in an ecosystem It’s a group of organisms of the same species that live in a particular area It’s a group of populations that live in a particular area and interact with one another It’s the physical location where different species live These are categories of organisms that can produce offspring that can also breed The fur seal population of St. Paul Island, off the coast of Alaska, has experienced dramatic fluctuations. What are some challenges in counting this population? It is difficult to count the seal population because : ◦ the animals are always moving ◦ the large colonies are randomly dispersed in the habit ◦ the habitat is partly terrestrial and partly aquatic. Individuals are added through births and immigration. Individuals are removed through death and emigration. Births Immigration Population size Emigration Deaths Environmental and social factors influence spacing of individuals in a population. There are three major population dispersion patterns. www.biology.iupui.edu/biocourses/N100/2k4ch39pop.html A uniform dispersion is one in which individuals are evenly distributed. It may be influenced by social interactions such as territoriality. In a random dispersion, the position of each individual is independent of other individuals. In a clumped dispersion, individuals aggregate in patches. A clumped dispersion may be influenced by resource availability and behavior. There are a number of techniques used to estimate a population and calculate a population density including: A. Transect sampling B. Quadrat sampling C. Mark-recapture sampling All these require the use of random sampling in which all individuals in the population have an equal chance to be represented. Transect Sampling Transects are useful when the terrain is varied. http://www.georgiastrait.org/?q=node/617 The area to sample is divided into blocks or quadrats. All of the target organisms in the quadrat are counted. Also used for stationary organisms like plants. Coml.org To calculate population for transects and quadrats use the following formula. To determine population density use the formula : ◦ DP = N Sampled -------------Area Sampled Now the total population of the study area can be calculated by extrapolation. ◦ NTotal = DP x Area Total This technique is better for organisms that move around. The animals are trapped and marked with a band or tag attached to their body. Awhile later, animals are trapped again in the same location. Some of the animals will have tags and some will not the second time. N # caught first time x # caught sec ond time # marked individual s recaptured www.pelicannetwork.net/bigsur.bird.banding.htm This is a Spotless Crake, a New Zealand bird that lives in wetlands. What sampling method is best to estimate this population? Explain why. These are periwinkle snails, a small, edible species that lives in an intertidal zone. What sampling method is best to estimate this population? Explain why.