Physical Features of a Stream and How They Affect the Macroinvertebrate Population
We will look at topographical maps of the area surrounding our stream sites. We will read information about the physical features of our streams in the Maryland Biological Stream Survey, and compare the invertebrate populations of a given stream with its physical characteristics.
Objectives
The students will be able to identify different kinds of land usage along the stream where the leaf packs were placed.
Students will be encouraged to think about how these land uses effect the quality of the stream and the invertebrate population.
Students will be able to identify physical features of a stream such as variety of water flow, quality of buffer, stream depth, oxygen, pH level, effects of erosion, and the quality of the stream bottom.
Students will read about a stream in the Maryland Biological Stream Survey.
Students may be able to visit the stream and carry out biological, chemical and physical tests. Students will be able to explain why a particular stream has produced a particular population of macroinvertebrates.
Materials
Topographical maps of each of our stream sites
Copies of Maryland Biological Stream Survey (MBSS) information for the stream sites
Color overheads of topographical maps showing stream corridors
Overheads of MBSS information for stream sites
Procedure
1.  Teacher will guide students by defining the land usage around a given stream corridor.
2.  Teacher will help students to locate key information in the Maryland Biological Stream Survey about the physical conditions of the stream. 3.  Students and teacher will compare 2 streams on the basis of land usage and their physical conditions.
4.  In small groups students will list the kinds of land usage and the kinds of physical conditions that a particular stream embodies using the MBSS information and the topographical maps.
5.  Students will chart these lists of information.
6.  Discuss the types of land usage surrounding a particular stream and the physical conditions of that stream.
7.  Students will make predictions, and explain their predictions about the kinds of bugs that might occur in the stream, or they will explain why this stream has a particular invertebrate population.
References
* Information about the physical features of streams gleaned from Maryland Biological Stream Survey information on particulary streams: http://mddnr.chesapeakebay.net/mbss
State Standards
1.2.6- The student will identify appropriate methods for conducting an investigation (independent and dependent variables, proper controls, repeat trials, appropriate sample size, etc.).
1.7.1- The student will apply the skills, processes, and concepts of biology, chemistry, physics, and earth science to societal issues.
6.2.2- The student will explain why interrelationships & interdependencies of organisms contribute to the dynamics of ecosystems. At least — Interspecific and intraspecific competition Niche Cycling of materials among organisms Equilibrium/cyclic fluctuations Dynamics of disturbance and recovery Succession: aquatic and terrestrial
6.3.3- The student will evaluate the interrelationship between humans and land resources. At least — wetlands soil conservation mining solid waste management land use planning human health
6.3.4- The student will evaluate the interrelationship between humans and biological resources. At least — food production/agriculture forest and wildlife resources species diversity/genetic resources integrated pest management human health
6.4.2- Design and conduct the research. Methods of data collection may include field or laboratory questionnaire/opinionnaire
Lesson Resources