Objectives. Stream Ecology. What is a watershed? Stream networks or drainages. Spatial scale: Stream segments 6/23/2010

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1 Objectives Stream Ecology Workshop 3: Ecology and Hydrology for the Lower Great Lakes W.J. Edwards, Niagara University Learn basic stream ecology Be able to identify stream macroinvertebrates Use simple Index of Biotic Integrity in Ellicott Creek Get wet and dirty Use a microscope What is a watershed? What is a watershed? Spatial scale: Stream segments Stream networks or drainages

2 Stream order A method of classifying or ordering the hierarchy of natural channels. Strahler (1957) is the most widely used system. Stream order correlates well with drainage area, but is also regionally controlled by topography & geology. Stream corridor and channel morphology 15.jpg Stream corridor and channel morphology Meandering rivers A meander becomes more pronounced as the streamline shifts between the river banks. Formation of an oxbow lake Sinuosity: Gradient and substrate Big meanders low gradient fine substrates Small meanders high gradient coarse substrates Braided channel Braided Pattern = high slope + high stream power + coarse bed materials earthsci.org/teacher/basicgeol/stream/stream.html#erosion%20by%20streams 2

3 Rocky River Metroparks, Cleveland, OH Riffles, pools, and cascades Riffles and pools alternate in somewhat predictable patterns Pool riffle sequence Riffle to riffle = 5 7 channel widths Current Current influences: Ecological distribution Morphological adaptations An organism s behavior 15.jpg A mayfly larva with a dorsoventrally flattened body minimizing drag in current. A collembola with a rounded body, suiting it for areas of slow current. Current and body shape Current Sunfish and bullheads with broad body forms are adapted to slow current. Stonecats and trout with streamlined body forms are adapted to fast current. inn.com/new images/ trout sm.jpg The distribution of diatoms, algae, and rooted macrophytes are influenced by current. Diatoms species can by sorted into taxa that are adapted to slow and fast moving water. Attached algae appear to increase in abundance in conditions with fast current and hard substrates. Rooted macrophytes thrive in slow water with soft sediments

4 The effect of substrate on organisms The diversity of materials making up the substrate of a stream make it complex and dynamic. The composition of the substrate plays an important role in shaping what organisms inhabit a particular stream reach. Due to other factors such as current, temperature, and oxygen levels it is important not to attribute the presence or absence of a specific species solely to the substrate type encountered at particular site. 18 mi Creek at Burt Dam Outdoors.webshots.com Boulder Cobble Pebble Particle size Category Dia (mm) Wentworth scale Large Small Large Small Coarse Medium Small Very Coarse Coarse Medium Fine Very Fine > 256 < Gravel Coarse Sand Silt < > Organic matter as a substrate component Organic materials ranging from plants stems to logs tend to function as substrates for organisms, while particles less than 1 mm in size may serve as food dfor macro invertebrates. Diversity and density of invertebrates often increases with the presence of organic matter as part of the substrate. As organic matter increases in stream substrates, macro invertebrate diversity tends to increase canal/lock_60.htm Faunal selection of substrates Group Preferred Substrate Lithophilous Gravel, Cobbles, Boulders Psammophilous Sand Xylophilous Wood Phytophilous Plants Fish spawning habitat Most stream dwelling fish select a hard substrate, ranging from large stones to mixed gravel on which to spawn. The availability and distribution of a particular substrate type necessary for spawning is often critical in creating suitable habitat for a particular species. The effect of temperature on organisms This figure illustrates seasonal differences in the emergence of mayfly species that would in part be cued by temperature. Where are the logs?! 4

5 Maximum daily temperature range in relation to stream order in temperate streams Oxygen In most unpolluted streams dissolved oxygen is near saturation and is, therefore, of minor biological concern. Current serves to deliver oxygen rich water to respiratory structures. Fish can actively move water over gills, however, most invertebrates cannot and are dependent on current to deliver oxygen. These organisms are referred to as respiratory conformers: their respiratory rate closely follows the ambient oxygen concentration. Oxygen related adaptations Periphyton Fish actively swim and draw water over their gills Macroinvertebrate larvae with conspicuous gills are respiratory conformers Midge larvae with hemoglobin are adapted to live in poorly oxygenated stream sediments ww.usask.ca/biology/skabugs/ephem/mayfly.html Periphyton is a complex matrix of algae and heterotrophic microbes attached to submerged substrata in almost all aquatic ecosystems. It serves as an important food source for invertebrates and some fish, and it can be an important sorber of contaminants. flies/chiron.html Periphyton components Attached and benthic populations Lotic phytoplankton include: Algae Protozoans Cyanobacteria Hoffman Image Gallery phytoflagellates (euglenophyta) Biodidac Hoffman Image Gallery These are small enough to remain suspended in the water column and be transported by currents. Many blue green algae grow attached on the surface of rocks and stones (epilithic forms), on submerged plants (epiphytic (ppy forms) or on the bottom sediments (epipelic forms, or the benthos) of rivers. Hoffman Image Gallery The epiphytic flora of lotic communities is usually dominated by diatoms and green algae, and bluegreens are of less importance in this community. Biodidac green algae (chlorophyta) Hoffman Image Gallery blue green algae (cyanobacteria) Diatoms University of Wisconsin Botanical Images Collection 5

6 Algal primary productivity Photosynthesis Light Temperature Nutrient Chronic toxicity Velocity Washout Loading Turbulent Velocityy Algal biomass diffusion Available substrate Grazing Mortality Acute toxicity Sinking Velocity Respiration/Excretion High temperature Stress Macrophytes Westlake (1975a) identified four primary growth forms: 1) Emergents occurring on river banks and shoals typically are rooted in soil that is near or below the waterline and have aerial leaves and reproductive structures; 2) Floating leaved species occupy margins of slow current areas, are rooted in submerged soils, and have aerial or floating leaves and reproductive structures; 3) Free floating species are typically not attached to the substrate and often form mats that entangle other species in slow flowing tropical rivers; 4) Submerged species are rooted to the substrate, have submerged leaves, and are located in mid channel to the point of insufficient light penetration. Macrophyte growth forms Stream invertebrates Emergents: banks and shoals Floating leaved: stream margins Free floating: slow (tropical) rivers Submerged: midstream (limited by light penetration, current speed, and substrate type) Emergent Free floating tml?pic=../photos/birdseyenupharsm.jpg cce.cornell.edu/onondaga/watersheds/images/milfoil.jpg Floating leaved Submerged Much of the aquatic life in streams is composed of benthic macroinvertebrates. The term macroinvertebrate includes clams, crayfish, worms, and insects. Macroinvertebrates donot haveinternal skeletons, are larger than 5 microns, and, typically, live on a stream substrate (bottom, woody debris, macrophyte, etc..) photo source: North American Benthological Society Adaptation to life in streams and rivers Introduction to taxonomy General life cycle Introduction to functional roles Insects Morphological adaptations to running water Adaptation Significance Representative Groups and Structures Dorsoventrally Flat Streamlining Reduced projecting structures Suckers Friction Pads Allows crawling in slow current boundary layer on substrate Fusiform body minimizes resistance to current Reduces resistance to current Attach to smooth surfaces Increased contact reduces chances of being dislodged Odonata Gomphidae Trichoptera - Glossosoma Ephemeroptera Baetis Diptera - Simulium Ephemeroptera - Baetis Diptera - Blephariceridae Coleoptera - Psephinus Comments Relatively rare body form Large lateral structures exist in some groups Rare adaptation 6

7 Morphological adaptations to running water Adaptation Significance Representative Groups and Structures Small size Silk and sticky secretions Allows use of slow-current boundary layer on top of substrate Attachment to stones in swift current Diptera Simulium Trichoptera - Hydropsychidae Ballast Cases made of large stones Trichoptera - Goera Attachment claws /dorsal processes Reduced power of flight Hairy bodies Hooks or Grapples Stout claws aid in attachment to plants Prevents emigration from small habitats Keeps sand/soil particles away while burrowing Attachment to rough areas of substrates Ephemeroptera - Ephemerella Plecoptera - Allocapnia Ephemeroptera - Hexagenia Coleoptera - Elmidae Comments Stream animals are smaller than stillwater relatives Reduces dispersal ability Allows water flow over body Order Aquatic insect orders Number of North American aquatic species (estimated) Ephemeroptera (mayflies) 572 Odonata (dragonflies and 357 damselflies) Plecoptera (stoneflies) 582 Trichoptera (caddisflies) Larvae Adults Aquatic insect orders Aquatic insect orders Order Number of North American aquatic species (estimated) Larvae Adults Order Number of North American aquatic species (estimated) Larvae Adults Diptera (flies and midges) Megaloptera (alderflies and dobsonflies) 43 Hemiptera (true bugs) 410 Neuroptera (spongilla flies) Lepidoptera (moths) Coleoptera (beetles) Hymenoptera (parasitic wasps) 55 Macroinvertebrate functional roles in organic matter processing Shredders Dominant food Vascular macrophyte tissue Coarse particulate organic material (CPOM) Wood Feeding mechanisms Herbivores Chew and mine live macrophytes Detritivores Chew on CPOM Representatives Scathophagidae (dung flies) Tipulidae (crane flies) A caddisfly of the family Limnephilidae Macroinvertebrate functional roles Collectors Dominant food Decompose fine particulate organic matter (FPOM) Feeding mechanisms Filterers Detritivores Gatherers Detritivores Representatives Filterers» Hydropsychidae» Simulidae (black flies) Gatherers» Elmidae (riffle beetles)» Chironomini» Baetis» Ephemerella» Hexagenia A caddisfly of the family Hydroptilidae A blackfly of the family Simulidae 7

8 Macroinvertebrate functional roles Scrapers Dominant food Periphyton (attached algae) Material associated with periphyton Feeding mechanisms Graze and scrape mineral and organic surfaces Representatives Helicopsychidae Psephenidae (water pennies) Thaumaleidae (solitary midges) Glossosoma Heptagenia A dipteran of the family Thaumaleidae Macroinvertebrate functional roles Predators Dominant food Living animal tissue Feeding mechanisms Engulfers Attack prey and ingest whole animals Piercers Pierce tissues, suck fluids Representatives Engulfers» Anisoptera (dragonflies)» Acroneuria» Corydalus (hellgrammites) Piercers» Veliidae (water striders)» Corixidae (water boatmen)» Tabanidae (deerflies & horseflies) A stonefly of the family Perlidae A true bug of the family Notonectidae Other macroinvertebrates General organic matter pathway Annelids (leeches and aquatic worms) Molluscs (clams, mussels, and snails) Crustaceans (crayfish, amphipods, and mites) geography.uoregon.edu/.../scrfig2 33web.jpg Sources of organic matter Fate of organic matter Autochthonous instream Allochthonous out of stream nz/shmak/ manual/6doing.htm Organic matter that enters streams may be (percent estimates are approximate and variable): Stored within the stream bank or channel (25%) Exported ddownstream (50%) Metabolized and respired as carbon dioxide by organisms (25%) Photo g. merrick /streamwatch/ swm10.html veg/brfredmaple.html 8

9 The River Continuum Concept Stream order and the RCC Low order streams Shaded headwater streams Coarse particulate matter (CPOM) provides resource base for consumer community Stream order and the RCC Mid order streams Energy inputs change as stream broadens Shading and contribution of CPOM decreases Sunlight supports significant periphyton production Upstream processing of CPOM results in input of fine particulate matter (FPOM) Stream order and the RCC High order streams As streams widen even more and flows drop, macrophytes become more abundant In the largest rivers, macrophytes are limited to the river margins because mid channel conditions are typically too turbid Bottom substrate becomes smaller Carbon fluxes in a stream ecosystem Figure

10 Think like a scientist. 10

11 MONITORING, MECHANISMS, AND MACRONUTRIENTS: MICROCYSTIS IN THE MAUMEE AND SANDUSKY SYSTEMS Douglas D. Kane 1, J.D. Conroy 2,3, D.L. Bade 4, W.J. Edwards 5, D.A. Culver 6, JD J.D. Chaffin 7, K. Wambo 8, CL C.L. Gruden 8, and T.B. TB Bridgeman 7 1. Natural Science and Mathematics Division, Defiance College, Defiance, Ohio 2. Aquatic Ecology Laboratory, Department of Evolution, Ecology, and Organismal Biology, The Ohio State University, Columbus, Ohio 3. Inland Fisheries Research Unit, Division of Wildlife, Ohio Department of Natural Resources, Hebron, Ohio 4. Department of Biological Sciences, Kent State University, Kent, Ohio 5. Department of Biology, Niagara University, Lewiston, New York 6. Limnology Laboratory, Department of Evolution, Ecology, and Organismal Biology, The Ohio State University, Columbus, Ohio 7. Department of Environmental Sciences and Lake Erie Center, University of Toledo, Oregon, Ohio 8. Department of Civil Engineering, University of Toledo, Toledo, Ohio Roadmap Part I: Determining bloom trigger points Measuring pools and process Quantifying Microcystis abundance Part II: How should we monitor and measure Microcystis? Problem: Where & When do blooms start? Spac ce Lake Bays Rivers Tribs????? Early spring Time Late summer 11

12 Methods: Data Collection Methods: Sampling locations Laboratory Analysis Field Sampling Heath, R.T Methods Algal Phosphorus Debt (P debt): Amount of phosphate incorporated in 24 hours in dark The more phosphate starved algae are the more phosphate is taken up Scaled to algal biomass Values above µmol P/ µg chl are considered P limited Phosphate Turnover Time (P turnover): Fast turnover times (less than 60 minutes) indicate P limitation Fast turnover times could be caused by a small phosphate pool or high demand by algae Healey & Hendzel 1979 µmol P/ µg Chl. a Sandusky System Results Sandusky P-debt Indicates agreement with P turnover data Site LIMITED NOT LIMITED May/June July August Septemb October Limitation Maumee System Results Sandusky NO µg N/L May/June July August September October 10 1 Maumee P-debt µg P/L Site Sandusky Total P Site May/June July August September October g Chl a µmol P/ µ Indicates agreement with P turnover data Site LIMITED NOT LIMITED May/June July August September October Limitation 12

13 µg N/L Maumee NO Site Maumee Total P May/June July August September October Nutrient Summary Sandusky system P limited in 40% of the samples Maumee system P limited in 70% of the samples Lake and tributary sites variable µg P/L Site 3 4 May/June July August September October Sandusky Bay generally not P limited Maumee River generally not P limited Roadmap Results: Microcystis biomass Part I: Determining bloom trigger points Measuring pools and process Quantifying Microcystis abundance Part II: How should we monitor and measure Microcystis? Results: Microcystis biomass Results: Microcystis biomass 13

14 Results: Microcystis biomass Results: Microcystis biomass 1970 Cyanobacteria biomass = 1 g m 3 April tributary Microcystis biomass = g m 3 Only four samples without Microcystis! Where & When do blooms start? Microcystis present in 0.3 m deep, 1st order streams Biomass in main stem rivers, bays, and the open lake Microcystis occurs by late April Microcystis abundant through October Current Microcystis biomass = 1970 s Cyanobacteria Where & When do blooms start? Spa ace Lake Bays Rivers Tribs Early spring????? Time Late summer Future Directions Physical Transport Modeling Genetic Analysis of Microcystis 14