The Diversity of Maryland Streams
Students will watch the Department of Natural Resources video entitled, Maryland Streams: An Undiscovered Realm.  Geomorphologically, MD streams are designated under one of the following three categories: western mountain streams, Piedmont plateau streams or coastal plains streams.  The video orally and visually describes the geological, physical and chemical characteristics of these three stream categories including the biological communities found in each of the watersheds.

By drawing from the text, Watershed Dynamics, by William S. Carlsen, students will explore how key physical and chemical factors vary within watersheds, and which characteristics determine the character and diversity of their respective biological communities. Physical characteristics will focus on temperature, turbidity and rates of flow.  Chemical Characteristics will focus on dissolved oxygen, pH, alkalinity, phosphorous, nitrogen and chloride.


Objectives
1. SWBAT Describe the major chemical characteristics that that determine the types of organisms that can live in a stream, including dissolved oxygen, nitrate, phosphate, alkalinity, pH, and chloride.

2. SWBAT Describe the physical characteristics of a stream that can 1) effect the chemistry of the stream and 2) the types of biological communities in a stream, including water temperature, turbidity, stream order, rates of flow and river substrate.

3. SWBAT to Give examples of how various land uses such as deforestation, agricultural development, mining and urban development can affect the chemical and physical qualities of a stream.
Materials
Video, Maryland Streams: An Undiscovered Realm.
Readings from Watershed Dynamics.
Readings from Maryland Streams: Take A Closer Look.
Procedure
1. Show Video, Maryland Streams (Sub-engagement and exploration). Students take notes and describe three major river/watershed categories in Maryland. Class discussion.
2. Assigned Readings, primary.  Students will be assigned readings in Watershed Dynamics by W.S. Carlsen et al which is part of the Cornell Scientific Series and published by NSTA press. Students will read, Chapter 1, "Introduction to Watershed Dynamics,"  Chapter 4, "Physical Characteristics of Streams," and Chapter 5, "Stream Chemistry" and answer chapter Questions.
3. Advanced assigned readings: From the Mountains to the Sea, The State of Maryland's Freshwater Streams, produced by the US Environmental Protection Agency and Maryland Streams: Take a Closer Look by MD DNR offer more technical appraisals of Maryland's freshwater resources for more advanced students.
References
Maryland Streams,  (video film) Written and produced by MD DNR (2002).
From the Mountains to the Sea: The State of Maryland's Freshwater Streams, Written by MD DNR and produced by EPA (1999). 9EPA/903/R-99/023, December 1999, www.epa.gov.
Maryland Streams: Take A Close Look, Written and produced by MD DNR (2000).
Watershed Dynamics, by Carlsen, W.S. et al, NSTA Press, Arlington, VA (2005).
State Standards
1.5.6- The student will read a technical selection and interpret it appropriately.
1.5.7- The student will use, explain, and/or construct various classification systems.
2.5.1- The student will investigate various physical cycles found in the natural world.
2.5.2- The student will analyze the effects of natural cycles on human activity.
3.5.1- The student will analyze the relationships between biotic diversity and abiotic factors in environments and the resulting influence on ecosystems.
3.5.2- The student will analyze the interrelationships and interdependencies among different organisms and explain how these relationships contribute to the stabilty of the ecosystem.
3.5.3- The student will investigate how natural and man-made changes in environmental conditions will affect individual organisms and the dynamics of populations.
3.5.4- The student will illustrate how all organisms are part of and depend on two major global food webs that are positively or negatively influenced by human activity and technology.
6.1.1- The student will demonstrate that matter cycles through and between living systems and the physical environment constantly being recombined in different ways. At least nitrogen cycle carbon cycle phosphorus cycle (rock/mineral) hydrologic cycle
6.2.1- The student will explain how organisms are linked by the transfer and transformation of matter and energy at the ecosystem level. At least Photosynthesis/respiration Producers, consumers, decomposers Trophic levels Pyramid of energy/pyramid of biomass
6.2.3- The student will conclude that populations grow or decline due to a variety of factors. At least Linear/exponential growth Carrying capacity/limiting factors Species specific reproductive factors (such as birth rate, fertility rate) Factors unique to the human population (medical, agricultural, cultural) Immigration/emigration Introduced species
6.3.2- The student will evaluate the interrelationship between humans and water quality and quantity. At least fresh water supply point source/nonpoint source pollution waste water treatment thermal pollution Chesapeake Bay and its watershed eutrophication human health
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
Lesson Resources