LICHENS AND ATMOSPHERIC CYCLESIn today’s activity we will be examining two nutrient cycles, the carbon cycle and the water cycle, as well as their impacts on lichens, a community of organisms that can provide information about air quality.Part I: What is a Lichen?1. At first lichens may look like a single organism, but they are actually a community of two or more species living together. Different species living in close association over time is called symbiosis. In the case of the lichen, the structure we see is a fungus, and living inside the fungus is one or more different species that can photosynthesize. We will cover photosynthesis in more detail next week, basically it is a chemical process that uses sunlight energy to convert carbon dioxide into sugars and other organic compounds. Pigments, particularly green pigments, are involved in absorbing sunlight. Which green organisms do we usually think of when we think of photosynthesis? ________________ 2. Microscopic species of algae and cyanobacteria can also photosynthesize, these are the organisms living inside of fungi making up the lichen community. Study the lichen at your table.The primary structure you can see is the _________________, also called the mycosymbiont (meaning “fungus partner”), the greenish color (or blue-green) is from the smaller organisms living inside, either __________________ or ____________________, also called the photosymbionts (meaning “photosynthetic partners”). Now you will rotate through four stations to learn more about lichens and their relationships to nutrient cycles and pollution.Part II: Lichen StationsStation A: Lichens, Water, and Air PollutionWater Cycle1. Using the Water Cycle poster as a reference, sketch and label the water cycle, including precipitation, condensation, run-off, groundwater, evaporation, and transpiration (evaporation from plants). 11Objectives for Exam #1:1. List and describe the basic processes within the water and carbon cycles.2. Discuss the structure, classification, and uses of lichens.3. Explain how aspects of the water and carbon cycles, as well as pollutants, can impact lichens.Objective for Portfolio #1:Identify, draw, and label lichen organisms viewed with a microscope.Clean-up:After making and viewing your lichen slide, rinse the slide and cover slip and put them in the bins by the sink. Leave the stations in good condition for the next class.Safety:Microscope slides can break easily. Report any broken glass.2. There are three types of precipitation, water does not only fall to the ground in liquid form as rain, it also precipitates in frozen form as _______________ and precipitates in gaseous form as _____________ .Acid Precipitation3. Many compounds react with water molecules as the move from one part of the water cycle to another. From the poster, sulfur dioxide can react with water to produce __________________and nitrous oxide can react with water to produce ________________________.4. Some species of lichens are extremely sensitive to acidic precipitation. One lichen in particular, Lobaria pulmonaria (“tree lungwort”) is extremely susceptible to acidic conditions, it cannot even grow on acidic barks. From the map provided, Lobaria can be found ___________________________________. From the Plants of the Pacific Northwest Coast book (which includes lichens too), what does Lobaria pulmonaria look like (p. 489)? _____________________________________________ Easy to identify appearance and widespread distribution make Lobaria a commonly used biotic indicator of acid precipitation inthe environment. Biotic indicators are organisms used to detect particular aspects of environmental conditions (like acidity, pollution, climate, etc.).Other Air Pollutants and Lichens5. Using the Air Pollution Chart (also reproduced as a smaller green handout), list major air pollutants in addition to nitrous oxide and sulfur dioxide:6. Lichens can be used a biotic indicator species for many air pollutants. The first large-scale air quality monitoring program using lichens was started in the Pacific Northwest, following a protocol developed at OSU. The data is accessible from the U.S Forest Service National Lichens & Air Quality Database and Clearinghouse website (http://gis.nacse.org/lichenair/). Select Lichen Images from the left column and from the pull-down menu click on Effects of Pollution. How does the bark of red alder trees differ in areas with air pollution?Station B: Lichens and CarbonCarbon Cycle1. Using the Carbon Cycle poster as a reference, plants and other organisms like algae and cyanobacteria remove carbon dioxide from the atmosphere and use it for the process of ___________________. Carbon dioxide can leave the atmosphere and enter oceanic waters through the process of ___________________Through sedimentation of the remains of organisms, carbon can be stored in ______________ rocks (limestone). Over the long term, partially decayed organisms were converted into the fossil fuels: natural gas, oil, and coal. Through drilling and mining these can be removed from the earth, and the carbon dioxide from these fuels is released into the atmosphere through the process of ______________________.122. All organisms carry out the process of respiration. Respiration is using sugars and oxygen for cellular activity, releasing carbon dioxide, a bit of water, and heat energy. Some organisms canalso carry out photosynthesis, which is almost the opposite reaction. Photosynthesis requirescarbon dioxide and ______________ in the presence of sunlight energy to produce sugars andoxygen. 3. In drought conditions, like summer in Corvallis, the organisms in a lichen community can be relatively inactive. From the data provided, explain what happens to photosynthesis and respiration in a lichen at low water content (approximately 20%) and high water content (approximately 75%).Lichen Growth4. Lichen communities are typically slow growing, some types grow less than 1.0 mm length/year. Lichens grow in three dimensions, but the primary growth for many species is in diameter. A lichen was traced on a piece of acetate. Looking at the acetate, approximately how long ago was this tracing made? _________________ Gently lay the acetate over the lichen, lining up the “X” marks on the tree bark with the marks made on the acetate. Using the provided ruler, approximately how much has the lichen grown in that time period? _________________mm. Has