3Eco section2 p81-148 · This activity is the introduction for your students, ... geraniums,...

A C T I V I T Y 20

111Exploring Ecology: 49 Ready-to-Use Activities for Grades 4–8

Line Transect:A Classroom Demonstration of the Method forSurveying a Small Community

IntroductionThe instructions in this activity are designed to help you preteach the major survey method yourstudents will be using to examine communities at school and on the field trip. This activity willbe new to most students, so demonstrating in class how to establish a line transect before you gooutside will answer many questions. Instructions are included here.

The line transect method uses only a small section of any large natural area, yet produces anaccurate representative sampling of the biotic and abiotic parts of a community. It is an excitingand stimulating activity, but does require a great deal of teacher preparation for it to be a success.

The time you spend preparing will make the results well worth your effort. Your students willspend several exciting days investigating and mapping their community using this method.

This activity is the introduction for your students, and it takes place in the classroom. Activity21 takes students outside on school property to practice making a sample community survey.

From the NSES—p. 32Encourage and model the skills of scientific inquiry, as well as curiosity, openness to new ideas anddata, and skepticism that characterize science.

ObjectiveThe student will be introduced to the purpose and function of a line transect, a method for ob-taining a representational survey of a community.

Materials• Line transect• 20 meters of string on a handle with a nail on one end of the string and the other end

attached to the wooden handle (instructions follow)• Student worksheet 21• Assorted plants and animals• 1-meter stick• Pen or pencil• Plain white paper (one piece per student)

Copyright 2005 NSTA. All rights reserved. For more information, go to www.nsta.org/permissions.

A C T I V I T Y20

112 National Science Teachers Association

Preactivity Preparation1. Constructing the line transect. Your technology department may be willing to make the handles

for the line transect from scrap material, or you could use square blocks of wood and wrap theline around that. Buy heavy kite string for the line and 5-penny spikes for the anchor. Measure20 meters of string and tie it to the wooden handle and wind up. Tie the spike to the otherend. It is helpful, but not necessary, to identify the 5-,10-, and 15-meter marks by usingcolored yarn or felt marker.

2. Gathering plants and animals for classroom instruction. A collection of the plants and animals—geraniums, gerbils, cacti, aloe vera, turtles, goldfish, spider plants—in the classroom can servethe purpose for this introductory lesson. If none is available or the variety is not adequate, cutpictures from magazines, glue them on sturdy paper, and attach feet at the base so the pictureswill stand up along the line. At least 5 to 8 plants and the same number of animals will beadequate.

Teacher InstructionsWhat is a Line Transect? (Teacher Demonstration)1. Hand out student worksheet 21 and a piece of plain paper to each student.2. Have students read the worksheet, define line transect, and write a reason for using one.3. Discuss the definition of line transect and relate that to the community study. What are the

problems when you try to measure and count entire populations of a community? Refer toActivity 10. (Populations are too big, no way to keep track of mobile animals that have beencounted.) The same results can be achieved by using a transect survey.

4. Setting up the line. Demonstrate as you talk.a. The nail is the 0-meter mark of the line transect. Outside it is pushed into the ground.b. Unroll the string. The handle end is the 20-meter mark.c. Place assorted plants and animals at intervals along the line. This demonstrates to students

how the line is set up to use in a community survey.5. Making a map of a community

a. The papers students have will become the map of the community.b. Students draw a line across the middle of their papers and label 0, 5, 10, 15, 20 meters on

the map to represent the line transect string.

c. All items along the line transect must be identified, measured, and counted and thenmapped.

d. Discuss various methods for identifying items with a symbol. Pictures, letters, or shortenedwords may be used. This is a chance for creativity.

e. Do a sample transect with your students.

0M 5M 10M 15M 20M


A C T I V I T Y 20


1) Go to the 0-meter mark on the line, identify the first population for the students.Locate the 0-meter spot on the students’ papers, and label the population found therewith an appropriate symbol. It is helpful to survey the entire line transect, first recordingplant information (height should be measured in centimeters and recorded), and thenreturning to look for animal information.

2) Each plant population should be mapped at its appropriate position, identified, andmeasured.

3) After completing plants, go back and record animal information. Animals are notmeasured.

4) Check to make sure students have recorded all information you have given them.5) Discuss the method with students, and make sure they understand the method for

survey of any community.6) Point out to your students that a major difference between this demonstration and the

outside experience is that inside you are providing only a few plants and animals.Outside, across a grassy lawn, through a grove of trees, or over a vacant lot, the studentswill encounter hundreds of plants, insects, and possibly several animals.

7) Roll up the line transect.


A C T I V I T Y21


Line Transect:Using the Line Transect Method in the Field

Please read the instructions for Activity 20 before beginning this activity.

From the NSES—p. 123Skills necessary to become independent inquirers of the natural world.

ObjectiveThe student will use the line transect method to map the biotic factors (plant and animalpopulations) of a community.

Materials• Line transects, one per student group• Meter sticks, one per group• 8 long pieces of surveyor’s tape or brightly colored ribbon• Plain white paper, one piece per student• Clipboard or folder provided by each student• Pencils• Appropriate outside dress• Optional whistle

Preactivity Preparation1. Before you take your students outside, go out yourself and choose the community sites your

students should survey. Identify each site with the surveyor’s tape or ribbon. Tie it on aconvenient branch at eye level. These are the points for the beginning of the surveys. Studentswill place nails in the ground at these points and roll the lines out to their full extents.Students will return to the tape markers each day.

2. Prepare the line transects. (See Activity 20.) You need one transect per group. The classshould be divided into four groups, 5 to 7 students per group. Each group should select co-leaders to share organizational responsibilities. These groups will work together for thein-school activities as well as the major field trip. (See “Grouping,” page 196.)

3. Collect meter sticks. Although rulers will work, meter sticks are easier to use.

Teacher Instructions (before leaving the classroom)1. Assign students to groups. Go over health and safety concerns.2. Pass out a line transect and meter stick to each group, pass out plain paper to each student,

and make sure each student has a pencil and a clipboard.


A C T I V I T Y 21


3. Have students review the concept of the line transect method and how to lay out the line.Emphasize that the nail is the zero mark and that they should push it into the soil to hold theline. The handle is the 20-meter mark.

4. Have students draw the map line on their papers before going outside. They will record allplant and animal population information along this line. Recording this information maytake students one to three class periods, 30 minutes per outside time, to complete.

5. Assign sites to each group.6. Ask for questions.7. Tell students the outside rules.

a. Students must not run or shout.b. Emphasize that this is a science project and students have a task that must be completed.c. Students may not visit other groups under any circumstances.d. All members of the group must help with the work.e. One person must be responsible for each piece of equipment.f. Students must obey signals to return to starting point. (A whistle is helpful.)

Teaching Tips1. The transect (survey site itself) is 20 meters long, 2 meters wide, and as high as the sky.2. All populations within this space must be identified, counted and measured, and then recorded

on the map. If students cannot identify a population immediately, encourage them to draw orwrite descriptions, or possibly collect a sample for field guide study when they have returnedto the room.

3. The use of a legend is very effective. Symbols represent populations and are placed on theline at the proper mark. All members of the group must agree on the symbols used. (SeeSample Line Transect A and Sample Line Transect B. In these samples, the legend is builtinto the line transect itself.)

4. Measure large populations by estimating. Count a specific area, then multiply by the numberof areas being considered. Estimate tree height by holding a meter stick against the trunk andestimating the number of meters to the top of the tree.

5. Anything that flies or leaps across the line is counted—birds, insects, squirrels.


A C T I V I T Y21


Samp

le Lin

e Tran

sect A


A C T I V I T Y 21


Sample Line Transect B

0 GRASS, BUTTERCUP, MOSS, CLOVER

BUTTERCUP, GRASS, WILD STRAWBERRY

5 BUTTERCUP, WILD STRAW., CLOVER, GRASS,DANDELIONS

DANDELION, CLOVER, FERNS

DANDELION, GRASS, CLOVER, FERNS, WILDSTRAWBERRIES, MOSSGRASS, MOSS

GRASS, HAY, MOSS

HAY, MOSS, WATER LILIES

10 GRASS, WEEDS, MOSS

MOSS, GRASS, WEEDS

GRASS

GRASS, CLOVER

GRASS, WEEDS, GOLDENROD, DOCK

15 THISTLE, GRASS

THISTLE, GRASS

GRASS

GRASS, WEEDS

GRASS, WEEDS

20 GRASS, WEEDS

GRACKELGREY SPIDER, FLIES, BUTTERFLY

SPIDER

TINY BLACK FLEA

ANT, RED SPIDER, FLEA

ANT, FLEA

FLOATINGBLACK SPIDER, LEECH BUGWATER BOATMAN, PAINTED TURTLE, LEECH

ORB SNAILWATER BEATLE, FROG

LITTLE GREEN BUG

FROG, MOSQUITOES

DRAGONFLY

MOSQUITOES, FROG

RED SPIDER

FLIES

FLEA, BLACK ANT

MOSQ., LEECH, GREEN BUG


21 Name _______________________________ Date _____________________


Line Transect:A Method for Surveying a Small Community

The line transect is a method ecologists use to investigate any community. Thismethod surveys a small section of a natural area. You will be able to locate, survey,and map the important parts of a community using the line transect method.

Define a line transect: _____________________________________________

_______________________________________________________________

_______________________________________________________________

Explain the purpose of the line transect: _______________________________

_______________________________________________________________

_______________________________________________________________

_______________________________________________________________

Your teacher will demonstrate how to set up and complete the map (the mapis actually a cross-section drawing) of any community using the line transectmethod. You will practice recording information on your paper while your teacherdemonstrates. All plants and animals should be located, identified, measured (plantsonly), and counted. Your completed map will provide a picture of the populationsin a community.


21Name _______________________________ Date _____________________


Instructions for OutsideA. Identify and count plant populations

l . Begin at the zero-meter mark (the point where the nail is in the ground).Identify plants along the first meter (and one meter to the sides) of theline.

2. Record the information on the map. Use a symbol to identify each species.Don’t forget to count and measure the size of each plant population andrecord this information.

3. If the same species is found at other places along the transect, use the samesymbol at each spot along the line.

4. Continue until all of the plant populations have been identified, counted,and recorded.

B. Identify and count animal populations1. Repeat steps number 1 through 3 above, locating animals.2. Animal size is not measured.3. Look closely on tree trunks, dig under ground, and look carefully under

logs or dead leaves for animals and insects.4. Birds, insects, and animals may be counted if they cross or fly over the line.5. Continue until all animals are named, counted, and recorded on the map.


3Eco section2 p81-148 · This activity is the introduction for your students, ... geraniums,...

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