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http://www.carolina.com/product/earth+and+environmental+science/ecology/population+biology/carolina& %23153-+population+density+and+biomass+study+kit.do QUADRANT SAMPLING-FIELD STUDY
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QUADRANT SAMPLING goal of the quadrant method is to estimate the population density of each species in a given community
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QUADRANT SAMPLING Before scientists can design an experiment: they must first make observations on which to base their hypotheses. Scientists have many different methods of collecting this data. The task of taking an inventory of the different kinds of organisms and their population sizes in an environmental site can be very difficult, especially if the area is teeming with life.
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QUADRANT SAMPLING Since it would be impractical, if not impossible, to count each individual organism in a large area, ecologists randomly choose small portions of the whole area, classify, and count the organisms in each small portion. They can then estimate the size of each population in the larger community. This process is called the quadrant method.
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QUADRANT SAMPLING Field study technique (indentify) Organisms are divided into five kingdoms: Monera, Protista, Fungi, Plantae, and Animalia abiotic factors of a study site Examples: Sun, water, wind, shade You will then measure randomly chosen quadrants within the site and count the individuals of each population located within each quadrant. With this data, you will estimate the sizes of plant and animal populations within the community.
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QUADRANT SAMPLING Identify a large area: For example, if a 10 m x 10 m (100 m2) site is being surveyed, three quadrants of a smaller size, perhaps 1 m x 1 m (1 m2), might be selected at random. Count species: If the population densities of a particular species at the three quadrants are 10, 12, and 14 individuals per m2, an average is taken of three smaller areas [(10 + 12 + 14/3 = 12 individuals per m2]. That number is multiplied by the ratio of the larger area to the area of each quadrant (100 m2/1 m2) to calculate the estimated population size within the site (12 x 100 = 1200 individuals). This process is repeated for all species in the community.
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