Figure 1a. What types of factors influence biological diversity in streams & rivers? Abiotic Factors Biotic Factors Biological Diversity 1
Figure 1b. How do abiotic and biotic factors interact to influence biological diversity in streams & rivers? Temperature Substrate Chemical Factors (Oxygen, Nitrates, Phosphorus) Light Current Biological Diversity Producers Competition Invasive Organisms Consumers Predation 2
Hours Days Weeks Months Years Decades Centuries Figure 2. Scale of Sampling and Analysis in Streams Individual Organism, Particle or Grain Population/ Community Microhabitat Community/ Ecosystem Pool-Riffle Sequence Ecosystem Reach Ecosystem/ Biome Watershed Millimeters Meters Kilometers Sq. Kilometers 3
Figure 3. Relationship of Diversity and Abundance Density. Number of Individuals/Stone or Density/Stone Number of Species per Stone 4
Figure 4. Relationship of Diversity and Watershed Area. Number of Species Watershed Area (square miles) 5
Figure 5. Relationship of Diversity and Sampling Effort. Number of Species Number of Samples 6
Figure 6a. Representation of River Continuum Concept Stream Order Organic Energy Sources Ecological Communities Shredders 1 Grazers Coarse Particulate Organic Matter Predators Collectors 2 Microbes 3 4 Periphyton 5 Collectors Shredders 6 Fine Particulate Organic Matter Predators Grazers Microbes 8 Phytoplankton 9 Zooplankton 10 Collectors 11 Dissolved Organic Matter Predators Microbes 12 Channel Width
Figure 6b. Pictorial Representation of River Continuum Concept
Figure 6c. Stream Order Determination Use what you ve learned about how to classify streams by stream order and for each of the streams on the hypothetical stream network determine stream order.
Figure. Two pathways for organic food in streams. Allochthonous Inputs Autochthonous Inputs Coarse Particulate Organic Matter Fine Particulate Organic Matter Leaves Diatoms Physical Breakdown Photosynthesis Scrapers Shredders Microbes Fine Particulate Organic Matter Predators Collectors Dissolved Organic Matter
Figure 8. Basic Food Web Illustration. Vertebrate Predators Insect Predators Vertebrate Herbivores Insect Herbivores Algae & Plants in the stream Microbes Organic Matter from outside of the stream
Table 1. Feeding Groups (Guilds) of Macroinvertebrates Feeding Group Resource Examples Shredders Leaves, twigs, stems, branches Trichoptera & associated microbes & fungi Plecoptera Diptera Coleoptera Crustacea Snails Filtering Suspended particulates, Trichoptera Collectors Microbes (especially bacteria), Simuliidae & Phytoplankton other Diptera Ephemeroptera Gathering Deposited particulates, Ephemeroptera Collectors Microbes (especially bacteria), Chironomidae Fungi Ceratopogonidae Grazers/Scrapers Periphyton & fungi Ephemeroptera Trichoptera Diptera Coleoptera Lepidoptera Predators Animals (especially invertebrates) Odonata Megaloptera Plecoptera Trichoptera Diptera Coleoptera
Table 2. The influence of substrate type on macroinvertebrate diversity and abundance (examples from a field study) from MacKay & Kalff, 1969. Substrate Type Abundance (number/sq m) Number of Species Sand 920 61 Gravel 1300 82 Pebbles & Cobble 2130 6 Leaves 3480 92 Detritus 5680 66 Graphic Presentation of Table 2. x Abundance (no./square meter (x) 5,000 o 100 o x x o o x 0 0 Sand Gravel Pebbles & Leaves Detritus Cobble x o Number of Species (o)
Table 3. Integrating morphology, behavior, gas exchange, and biological diversity What can the biological diversity of aquatic insects tell us about water quality and stream health? Aquatic insects show a variety of morphological and behavioral adaptations for obtaining oxygen. Even with an order (e.g. Flies, midges, or Diptera) we find a range of adaptations. Morphological adaptations for obtaining oxygen include some of the following examples: o Breathing tubes that can reach the surface and use atmospheric oxygen (e.g. mosquito larvae) o Soft tissue between body parts (e.g. most species) to allow diffusion of dissolved oxygen in the water into tissues in the organism o Soft tissue that is highly branched as gills (e.g. stoneflies, mayflies, damselflies) to allow diffusion of dissolved oxygen in the water into tissues in the organism o Hair-like structures combined with plate like wings that can trap atmospheric oxygen Behavioral adaptations are often combined with those listed above and may include some of the following examples: o Pumping the body up and down to move water across surfaces and increase diffusion rates of dissolved oxygen into tissues of the body o Swimming to the surface to trap a bubble of air and obtain atmospheric oxygen o Construct burrows or tubes and combine this with moving the body inside the tube or burrow to pump water through the tube or burrow and increase diffusion of oxygen dissolved in the water into tissues of the body Depending on the morphological and behavioral adaptations that a particular species has they may show differences in tolerance to lower oxygen conditions in streams than other species. For example, species that have morphological or behavioral adaptations that allow them to use surface air or atmospheric oxygen can survive in conditions of low levels of dissolved oxygen. Note species that have higher tolerance to low oxygen, can also survive in higher oxygen conditions.
Comparison of morphological and behavioral adaptations of families of stream dwelling aquatic insects in the Midwest (these are summaries of more extensive treatments in Bouchard, R. J. 2004. Guide to Aquatic Invertebrates of the Upper Midwest: Identification Manual for Students, Citizen Monitors, and Aquatic Resource Professionals. Ephemeroptera or Mayflies use abdominal gills to obtain dissolved oxygen. Baetidae Moderate Collector/Scraper Baetiscidae Low Collector Caenidae High Collector/Scraper Ephemerellidae Low Collector Ephemeridae Moderate Collector Heptagenidae Moderate Scraper Isonychiidae Low Filterer Leptophlebidae Low Collector Metretopidae Low Predator/Collector Polymitarcyidae Low Collector/Filterer Potamanthidae Moderate Collector/Filterer Siphlonuridae High Collector Odonata or Dragonflies obtain dissolved oxygen through soft tissue between plates and Damselflies use leaf like abdominal gills to obtain dissolved oxygen, Damselflies Calopterygidae Moderate Predator Coenagrionidae High Predator Lestidae High Predator Dragonflies Aeshnidae Low Predator Cordulegastridae Low Predator Gomphidae Low Predator Libellulidae High Predator
Plecoptera or stoneflies use thoracic gills to obtain dissolved oxygen. Capniidae Low Shredder Chloroperlidae Low Predator Leuctridae Low Shredder Nemouridae Low Shredder Perlidae Low Predator Perlodidae Low Predator Pteronrcyidae Low Shredder Taeniopterygidae Low Shredder Hemiptera or True Bugs may use atmospheric oxygen either via living on the surface or if they live in the water then they use atmospheric oxygen obtain through modifications of hair-like or tube-like on their abdomens. Belostomatidae High Predator Corixidae High Collector Gelastocoridae???? Predator Gerridae???? Predator Hebridae???? Predator Hydrometridae???? Predator Mesoveliidae???? Predator Naucoridae Moderate Predator Nepidae High Predator Notonectidae???? Predator Pleidae???? Predator Saldidae???? Predator Veliidae Moderate Predator Megaloptera or dobsonflies, fishflies, hellgrammites, alderflies obtain dissolved oxygen through diffusion across soft tissue Corydalidae Low Predator Sialidae Moderate Predator
Neuroptera or Spongillaflies obtain dissolved oxygen through diffusion across soft tissue. Sisyridae???? Predator Trichoptera or caddisflies obtain dissolved oxygen through diffusion across soft tissue sometimes combined with abdominal gills and pumping water through cases. Brachycentridae Low Collectors/Filterers/Shredders Glossosomatidae Low Scrapers Helicopsychidae Low Scrapers Hydropsychidae Moderate Collector/Filterer Hydroptilidae Moderate Scraper Lepidostomatidae Low Shredder Leptoceridae Moderate Collector/Shredder Limnephilidae Moderate Shredder Molannidae High Scraper/Collector Odontoceridae Low Scraper Philopotamidae Low Collector/Filterer Phryganeidae Moderate Predator/Herbivore Polycentropodidae High Collector/Filterer/Predator Psychomyiidae Low Collector Rhyacophilidae Low Predator Sericostomatidae Low Shredder Uenoidae Low Scraper Lepidoptera or moths obtain dissolved oxygen through diffusion across soft tissue. Pyralidae Moderate Shredder
Coleoptera of Beetles obtain dissolved oxygen through diffusion across soft tissue and atmospheric oxygen through modified hairs and plate-like wings. Dryopidae Moderate Scraper Dytiscidae Moderate Predator Elmidae Moderate Scraper Gyrinidae Moderate Predator Haliplidae High Shredder Hydrophilidae Moderate Predator/Collector Psephenidae Moderate Scraper Scirtidae High Scraper/Shredder/Collector Diptera or Flies obtain dissolved oxygen through diffusion across soft tissue including abdominal gills and atmospheric oxygen through breathing tubes. Athericidae Low Predator Blepharicidae Low Scraper Ceratopogonidae Moderate Predator Chaoboridae High Predator Chironomidae Moderate High All Guilds Represented Culicidae High Collector/Filterer Dixidae Low Collector Dolichopodidae Moderate Predator Empididae Moderate Predator Ephydridae Moderate All Guilds Represented Muscidae Moderate Predator Psychodidae High Collector Ptychopteridae High Collector Sciomyzidae Moderate Predator Simuliidae Moderate Filterer Stratiomyidae High Collector Syrphidae High Collector Tabanidae Moderate Predator Tipulidae Low Shredder/Predator/Collector