Ecology.pdf
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Ecology BIOL-2101 Prof. Dan Mennill Integrative Biology, University of Windsor 1 Lecture 1: & Introduction to Ecology Today: A symbiosis in Costa Rica Course logistics Chapter 1: Intro to Ecology...
Ecology BIOL-2101 Prof. Dan Mennill Integrative Biology, University of Windsor 1 Lecture 1: & Introduction to Ecology Today: A symbiosis in Costa Rica Course logistics Chapter 1: Intro to Ecology 2 biodiversity 3 Rufous-and-white Wren only Found (Thryophilus rufalbus)in Central America 4 ~ follow over course of life Rufous-and-white Wren (Thryophilus rufalbus) 5 6 nest always in same species of tree Bullhorn acacia (Vachellia collinsii) 7 - thornsten don't want to Bullhorn acacia (Vachellia collinsii) 8 not surrounded by regetation 9 10 Sting is inject acidic toxin * dig into skin bitting 11 found all over tree Stem Acacia ant (Pseudomyrmex ferruginea) 12 file into - bullhorns f live inside z most of stems Acacia ant (Pseudomyrmex ferruginea) 13 water + sugar nectary > - gives carbon needs base of leaf water get and sugar the patrolling plant 14 HAS EVERYTHING NEED TO LIVE Beltian body supply protein , lipids , carbohydrates 15 Sting - all over and eyes nose White-tailed Deer (Odocoileus virginianus) 16 eat anything White-faced Capuchin Monkey (Cebus capichinus) 17 Ant clearcut no nearby plants to join competition for light 18 Food and ant > - gets it everything needs lodging host gets Bodyguards decrease heribarory decrease competition “mutualism” 19 Wasps 20 Benefit : ant bodyguards ants tolerate them after awhile Rufous-and-white Wren (Thryophilus rufalbus) 21 ant toxin letnel to organisms other Vine Snake (Oxybelis aeneus) 22 Ecology BIOL-2101 Acacias Plants Wrens Monkeys Wasps Deer Snakes Ants 23 Ecology BIOL-2101 Prof. Dan Mennill Dept. of Integrative Biology, University of Windsor 24 What is ecology? The study of the relationships of organisms and their environment * The word “ecology” was coined in 1869: Oikos: Home Logos: Study of 45 WHY ? What is ecology? # found where they interactions are Ecology is separate from natural history (the descriptive study of organisms in their wild habitats) observation skills - Ecology is a systematic and quantitative enterprise 46 Abiotic environmental factors Organisms are influenced by factors of their environment, such - as temperature, - - moisture, nutrients, - fire, or toxins - abiotic us biotic ↓ ↓ not alive living (eX temp). 47 Biotic environmental factors Organisms are influenced by other organisms through competition, herbivory, predation, parasitism, disease, mutualism~don't involve host being killed 48 Abiotic and biotic interactions FIGURE 1.3 49 Ecosystems The fundamental unit in ecology Ecosystems include abiotic and biotic components · Ecosystems can be large (e.g. the biosphere) or small (e.g. the pitcher of a pitcher-plant) & insects + Salamander andabiotic mp) 50 Ecosystems The function of an ecosystem is described by productivity (rate of EX. increase in biomass), pitcher > rate - changes in nutrients plants (example: Nitrogen fixation), flow of energy, and flow of water 51 Organization of the universe FIGURE 1.5 52 Ecology Ecology 53 Ecology is a science Common features of ecological studies: – Field-based research – Sophisticated tools – Hypotheses testing – Statistical analyses 54 ↑ Ecology is a science Ecologists propose testable hypotheses related to organization and functioning of the natural world Research may rely on patterns observed in nature (correlational) or based on experiments, but always following the scientific method 55 Ecology is a science FIGURE 1.14 56 Ecology is Applicable Knowledge of ecology can be applied to management of natural resources Examples: forestry, agriculture, fisheries 57 Ecology is interdisciplinary Ex. nitrogen FIGURE 1.11 58 Ecology is a complex subject FIGURE 1.13 59 Ecology is a complex subject This course will lead you to other courses… UWindsor ecology courses offered most fall semesters: Fish and Fisheries (Fish Ecology) Ornithology (Bird Ecology) Plant Ecology Animal Communication (Behavioral Ecology) Pollution Ecology Conservation Biology (Conservation Ecology) Stream Ecology Limnology (Fresh Water Ecology) 60 Ecology is a complex subject This course will lead you to other courses… Upper year ecology courses offered most spring and summer semesters: Animal Behaviour (Behavioural Ecology) Community Ecology Invertebrate Biology (Insect Ecology) Speciation (Evolutionary Ecology) Evolutionary Endocrinology (Physiological Ecology) Great Lakes Biology (Aquatic Ecology) Field Ecology (through study abroad and field courses) 61 Summary Ecology is the study of the relationships between organisms and their environment Ant-acacia mutualism provides an example of complex relationships Ecology, unlike natural history, relies on the scientific method to test hypotheses Ecology is a multidisciplinary and complex subject area, and our goal is to survey many branches of ecology in this course 62 Ecology BIOL-2101 Prof. Dan Mennill Department of Integrative Biology, University of Windsor 1 Lecture 2: Environmental Influences Today: Chapter 2 Mangroves Environmental factors Environmental stressors 2 3 Map of global mangrove distribution most diverse mangrove trees in Southeast Asia Mangroves: More than 50 species of tree adapted to life in brackish water4 STRESSFUL ENVIRONMENT z The intertidal zone zone between the tide the water level f+ -m at high tide and the water level at low tide 5 & Satt water dehydrates king Salt metabolism take in all that salt wash HeO and rid of excess NaCl > - get shunt out of leaf 6 -ar STRESS ↳ water level is time changing all the set out roots to nutrients gather Of Pneumatophores , - LUNG roots 7 GERMINATED 8 Sexploiting water currents to move around ↳ grow in intertidal zone 9 Build land - forest line more foward 10 Filter runoff from Upland areas roots filter water that comes through - extract - What they need minerals ; nutrients vid of "Salt get metal - + - water is cleaner 11 Provide home for diverse biological Organisms 14 Produce off a lot organic waste 3 peer poop ↳ organic nutrients & serves as food 15 THREAT UNDER 16 of keep chunk mangrove forest 17 Mangroves - Abiotic Factor - - changing levels salt water Environmental factors Biotic Factor-crabs heron fish manatees Environmental factors: , , , features that affect individual organisms, populations, communities, landscapes, etc. May be biotic or abiotic, natural or anthropogenic Affect functions such as: Acadian hairstreak productivity, butterfly is influenced by biotic and abiotic decomposition, nutrient environmental factors cycling 18 Abiotic environmental factors How Mangroves Temperature grab energ a Sun Moisture Radiation Wind currents Water currents Nutrients Toxic substances Etc. Cranberry in wet, nutrient-poor habitats 19 Biotic environmental factors Other organisms another species same mangrove - tree Conspecific or competition ① next to you interspecific organisms - & different species Direct effects such as predation Indirect effects such as competition for resources Etc. Ferns in limited light of the forest understory 20 Limiting factors abiotic Mineral nutrients are - often a limiting factor for ecosystem productivity can be biotic or abiotic Limiting factor: factor with lowest availability relative to need Phosphorus often limits lake productivity… Additional Phosphorus Phosphorus is often may lead to limiting factor for lake productivity euotrophication ↳ becomes enriched with nutrients water body overly life 21 of leading to the plentiful growth simple plant Principle of limiting factors lowest limit factor Growth is controlled not ↑ by the total amount of resources available, but by the resource that is in - shortest supply - (e.g. growth > limit phosphorus in lakes) - - Developed by Justus von Liebig, the father of Organic Chemistry 22 Example: Lake eutrophication Aegar Blooms ↳ warm 3 lot of growth & lot of runoff of nutrients from the lands into Great Lakes Algal blooms in Lake Erie 23 DEPLEATED Of & Lake eutrophication 2 - -D ↑ eat toxins 24 We Dump lot of phosphorus into 1 the. environment Fertilizer Lake eutrophication. 2 Factor Washing Machine - Laundry Detergent & Limiting No longerO2 available - fish can't breath BOX 2.1 - algaeofbloom the consume O2 al 25 Lake eutrophication David Schindler Experimental Lakes Area University of Alberta of northern Ontario26 27 Oligotrophic Lake not a lot of nutrients - Lake Utropic - full of nutrients/life self contained lakes 28 Niche In most ecosystems, unfavourable conditions limit growth Niche: all environmental factors that limit distribution, growth, and reproduction of a species Geraniums have low Niche: the physical frost tolerance; grow in space occupied by an Ontario when sheltered from cold organism or species 33 Niche Fundamental niche: The complete range of conditions under which a species can establish, grow, and reproduce when it is free from interference Mangrove in tree middle of growing by itself Geraniums have low beach its fundamental niche occupying frost tolerance; grow in - free to grow no other Ontario when fighting mangroves all for soil sheltered from cold space got resources & Fundamental Niche : no extreme first frost 34 by Niche of conditions used set actually givenanimalafterinteractions a and taken into competition) - has been account Realized niche: the observed resource used by a species in nature, where distribution is restricted by environmental factors Narrower than fundamental niche Oriental lilies tolerate Ontario climate, but do Fundamental Niche of Mangrove. - not survive in face of weeds and herbivory soil Anywhere w and tropical sunlight Realized of G Outcompeted by other organisms Where ocean Niche meets Mangrove fresh water - In Ontario realized niche does not exist -> COMPETITION 35 Adaptation, fitness Organisms can be adapted to stress The degree of adaptation influences the organism’s performance and fitness Dandelion is adapted to drought moreso than lawn grass 36 no moisture Genotype, phenotype offspring launch out into would > - lots of moisture & Genotype: genetic information that is encoded within DNA Phenotype: actual expression of genetic potential (depends on environment) Phenotypic plasticity allows acclimatization of a genotype to stress Shaded dandelions invest in leaves; exposed ones in seeds 37 Phenotypic plasticity Phenotypic plasticity: ability of an organism to change its phenotype in response to changes in the environment There are limits to how far a phenotype can “stretch” Genotype is your Fundamental Niche Phenotype is your Realized Niche 38 Struggleintorocks grow - invest in flower production to hope that their offspring off and will find go an even more nutrient-rich area to grow & produce bigger plant 39 Environmental stressors Stressor: Environmental factor that limits performance of organisms, populations, communities and landscapes Performance: Productivity and reproductive fitness, relative to genetic potential Quantify stressors in terms of impact on productivity, decomposition, nutrient cycling 40 Environmental stressors Exposure to stressors can: be instantaneous and intense (e.g. wildfire, hurricane) accumulate over long periods (e.g. toxicity, dessication) 41 Environmental stressors Tolerance (resistance): organisms, populations, communities, etc. have the capacity to function in a “healthy” manner within a range of environmental stressors Tolerance of an increasing intensity of environmental stress can take many forms 42 Environmental stressors Organisms tolerate stressors to different extents A shows an early response to stress; can serve as an early- warning signal rapidchangeslos exhibits initial , of + olerance D shows a late response to stress; high tolerance shows a after strong extended response only an but can often cause rapid of tolerance is range exceeded at threshold change FIGURE 2.7 43 Environmental stressors B responds steadily and provides a consistent measure throughout stressor C shows a stepwise response with rapid chance at certain thresholds, followed by stability FIGURE 2.7 44 Environmental stressors Resilience: speed and degree to which an organism, population, community, etc. can recover to its original state following an event of disturbance Jack Pine: high resilience to Atlantic cod: low resilience forest fire to over-harvesting don't to let open pine seeds burned 45 - out unless trees die but comes - forest open - new Categories of stressors Chronic stressor: long term influence (e.g. nutrients in water and primary productivity) Disturbance stressor: powerful but short-lived event (e.g. severe windstorm, fire, etc.) Natural stressors: present for very long time periods (eons) Anthropogenic stressors: stressors associated with human development 46 Types of stress Climatic stress: temperature, solar radiation, wind, moisture, combinations thereof Chemical stress: high concentrations that cause toxicity (e.g. lead, mercury) Wildfire: combustion of biomass Physical stress: e.g. volcanic eruption Biological stress: interaction among organisms 47 Invasive species Zebra mussels Round gobies Phragmites European starlings 48 Anthropogenic stressors Many stressors are caused by or modified by human activity: – Increased levels of toxic substances – Changed climate or hydrology – Diminishing of wild populations Pollutants along the Detroit river stress our local ecosystems 51 Pollution Human activity can locally increase the concentrations of natural substances such as metals The concentrations and ecological effects often decrease with increasing distance from the source Past emissions gave toxic concentrations of copper, nickel in Sudbury 52 Outcome of environmental stressors Decrease of productivity, increases in mortality, and reproductive failure – E.g. endocrine disruptors (see section 2.3 p.38) Sensitive species are replaced with tolerant species Top predators and large- bodied species are lost Male fathead minnows Species richness and feminized by exposure diversity decrease to birth conrol pills 53 Summary Mangroves exhibit adaptations to stress Environmental factors are features that affect organisms, populations, communities; biotic or abiotic Principle of limiting factors: growth is controlled by resource in shortest supply Natural and anthropogenic stressors have profound effects on ecology of organisms and ecosystems 54 Ecology BIOL-2101 Prof. Dan Mennill Department of Integrative Biology, University of Windsor 1 Lecture 3: Ecological Energetics Today: Chapter 3 Solar input to ecosystems Global warming Food chains and food webs 2 Ecosystem processes Two important processes occur in ecosystems: 1. Energy flows through ecosystems 2. Nutrients cycle through ecosystems 3 Ecological energetics Ecological energetics: the study of fixation, transfer, and storage of energy by ecosystem components Today we study how energy flows through ecosystems… Tuesday we study how nutrients cycle through ecosystems 4 Ecological energetics In terms of energy, ecosystems are open systems that require constant input of energy Solar radiation is the * # most important source of energy in most ecosystems Biosphere is an open system ↳ can't sustain itself in terms of energentic requirements 5 Solar energy The electromagnetic spectrum is a continuum of energy Photosynthesis uses visible light as it has energy levels suitable for capture by organic molecules Physics described on pages 46-50, for interested readers FIGURE 3.2 6 Solar energy and autotrophs Green plants, algae, and cyanobacteria absorb solar energy to convert carbon dioxide and water and turn it into sugar, with oxygen produced as a by- product * Sunlight + 6CO2 + 6H2O → C6H12O6 + 6O2 * d d SUGAR was te ↓ product Stay Alive 7 Release of solar energy Solar energy, fixed by autotrophs self in their biomass, can be used by beat sun other organisms for energy-requiring processes, or released as heat (e.g. fire) Most ecosystems run using this energy (solar energy fixed by autotrophs) 8 Delayed release of solar energy Some absorbed and biologically fixed energy can be stored for long periods as peat or fossil fuels & short periods - eat lettuce from garden - transfer solar energy to you ↳ convertintohydrocarbonas 9 Photosynthesis is heart of all energy absorbed on earth Other functions of solar energy The sun also heats Earth’s surface Provides energy for other ecologically important processes: – Evaporation of water – Circulation of atmosphere – Circulation of oceans 10 Seasons In temperate zone, seasonal variation in available energy by solar radiation causes major fluctuations in biological activity I 11 First law of thermodynamics Energy can be transformed but not created or destroyed F In any system, input of energy has to equal the amount of energy stored and the output of energy Earth receives an input of solar energy Solar input equals the amount reflected, transformed in chemical form, stored as heat, and dissipated energy 12 Second law of thermodynamics Energy transformations can occur spontaneously only under conditions in which entropy of the Universe is increased energy to is needed create order Energy is needed to create order and combat entropy Energy transformations can never be totally efficient; they require energy Life requires incessant input of energy, mostly from the sun 13 Solar energy Sunlight is reflected or absorbed The absorbed energy is dissipated by re- radiation of longer-wave infrared energy (heat) Absorbed sunlight and dissipated energy are almost in perfect balance FIGURE 3.6 14 70 % radiation incoming solar Y absorbed as heat in energy the upper atmosphere the more molecules that we have in the upper atmosphere CO2 + greenhouse higgaseso go solar of up sig portion energy driving nice greenhouse sitting around earth heat 15 far less We get solar radiation Solar energy even Ojibway = in the summer vs Rainforest Amount of solar radiation varies with latitude Canadas longitude - Spread out over greater a area way earth curves relative to the Sun 900 equator narrow Grech Sun is so far away from earth by the time radiation reaches earth it is parallel 16 Solar energy Solar transmission through the atmosphere also varies with latitude 17 Greenhouse gasses Natural greenhouse gasses (carbon dioxide, water, methane) absorb some of the dissipated infrared radiation and re-radiate it in allfordirections liquid Organisms is right temperature 3 Creates the environment water to be This provides Earth with a thermal blanket , use incomingsolarradiationsynthesis As a result, Earth’s average temperature is +15°C - instead of -18°C - 18 Increases in greenhouse gasses Combustion of fossil fuels, deforestation, and agriculture have increased the atmospheric concentrations of several greenhouse gasses taking captured in the sunlight form of carbon Molecules and then produceone ejecting them back out into atmosphere at increasing levels FIGURE 3.8 19 Hawaii ! n n middle of Pacific Ocean Measure CO2 20 Photosynthesis drops in winter is Opposite on earth water Constant steady march upwards Passappm 21 22 produce a lot more CO2 atmosphere has a lot more CO2 23 Increases in greenhouse gasses Combustion of fossil fuels, deforestation, and agriculture have increased the atmospheric concentrations of several greenhouse gasses - 2 absorb sunlight greenhouse gas global warning 24 Global warming Anthropogenic increases in greenhouse gasses cause warming of the global climate Warmer climate may increase productivity and decomposition, but also cause more drought Major changes in biotic and abiotic environmental features are occurring 25 Global warming From: Perry et al. (2005) Science 308: 1912-1915 26 Global warming ↳ all species shifted northward ranges deep ocean animals ↳ ClimateChanga A Cod organisms can live on earth B Anglerfish Photo: Bill Freedman C Snake blenny From: Perry et al. (2005) Science 308: 1912-1915 27 From New York Times, Sept. 3, 201628 Energy fixation in ecosystems turn solar energy into molecules Autotrophs are primary producers, providing energy stored biological foundation of ecological productivity as two carbons Photoautotrophs: tog Stuck light feeders self useSunlit to the – Plants energy transfer of into biomolecules – Algae – Cyanobacteria Chemoautotrophs: – Specialized bacteria ↳ live in deep oceanic vents ↳ pitch black ; no sunlight fom Earth's liquid in oras use heatenergy core biomolecules 35 ↳ Photoautotrophs creating energy bound up in Sugars through photosynthesis Photoautotrophs are responsible for almost all productivity in the biosphere up energy Sugars create in bound (photosynthesis) Chlorophyll and other sensitive to solar radiation pigments capture photons sugar solar radiation > - Sunlight - , CO2 HaO , Most sensitive to blue and red wavelengths of light, which is why leafs appear that green don't need light & energy they is reflected and that is reflected not used light 36 - grab red and blue parts of electromagnetic spectrum and use photosyn. Chemoautotrophs Chemoautotrophs are specialized bacteria that get energy from inorganic chemicals (e.g. by oxidizing sulphide minerals) The energy released by these exothermic reactions drives biosynthesis of CO2 and H2O to form glucose Example: at volcanic deep sea vents, chemoautotrophic bacteria provide all the energy for these very special ecosystems 37 organisms Heterotrophs other on all that are not Earth autotrophs Other-feeders Feed on other heterotrophs Herbivores Feed on autotrophs Carnivores feed on row autotrophs , 9 themselves heterotrophs use the fixed in order to energy the through grow of process decomposition Omnivores Detritivores38 Heterotrophs Other - feeders Note: not all plants are autotrophs ↳ cyanobacteria Example: Ghost pipe (Monotropa uniflora) has no 6. chlorophyll; it derives energy from surrounding trees via a mycorrhizal fungus not all plants can photosynthesize 39 Ecological productivity > - how quickly does the plant grow Productivity: rate at which energy is fixed (in mass is autotrophs) and rate at which biomass is org added to an anism accumulating (organisms and ecosystems) Measured on dry weight basis (due to water flux) Biomass standardized to area (tons of dry weight per unit area; t/ha) Productivity standardized per unit time (t/ha/year) ↳ amount of may go water up/down throughout day ↳ CO2 in dry mass 40 Ecological productivity Gross Primary Production: total amount of solar energy fixed by autotrophs nowdry much plot mass in that Respiration: amount of energy used by autotrophs for their metabolism (plants use ¼ to ¾ energy for respiration) Net Primary Production: gross primary production minus ↳ used respiration by autotrophs by autotrophs in of process NPP = GPP - R growing 41 42 Productivity of major biomes Most productive habitats with low environmental constraints: warm and humid climate, fertile soil Tropical Boreal rainforest: forest: 9.0 tC/ha/yr 3.6 tC/ha/yr ↳ net primary production Temperate Tundra: deciduous 0.65 tC/ha/yr forest: ↳ go w out sun 5.4 tC/ha/yr for periods of time ↳ solar radiation in is different coming 43 Productivity of major biomes Open oceans have low net primary productivity (0.57 tC/ha/year) because of low nutrient availability Reefs and estuaries have high productivities comparable to terrestrial ecosystems Reefs: Estuaries: 9.0 tC/ha/yr 8.1 tC/ha/yr Mangrove forest -> high level of net 44 Productivity and production Open oceans, in spite of their low productivity, account for a large amount of global production due to their vast area photosynthetic single organisms cell Global net production floating around – Total continental: 48.3 109 tC/yr – Total marine: 24.9 109 tC/yr – Total world: 73.2 109 tC/yr 45 Food chain Food chain: linear representation of feeding interactions and energy transfer Only a part of the energy of the food can be absorbed or utilized Herbivores assimilate 10% of energy in their food Carnivores assimilate 20% of energy in their food 48 Food web Food web: representation of all feeding inter- actions among the food chains in an ecosystem FIGURE 3.19 49 FIGURE 3.18 50 Energy transfer in ecosystems At each trophic level, a large part of energy is lost as respiration mostof energnation 80 % 90 % - FIGURE 3.20 51 Ecological pyramids Due to inefficiency of energy transfers, the productivity declines with increasing trophic level FIGURE 3.21 52 Predators and ecological energetics Number of predators that can be supported varies across ecosystems, based on ecological pyramids 53 Humans and ecological energetics “Three hundred trout are needed to support one person for a year. The trout, in turn, must consume 90,000 frogs, that must consume 27 million grasshoppers, that live off 1,000 tons of grass.” - Tyler Miller, Jr. American Chemist (1971) 1 person 80 %-90% of at energy each level is lost 300 trout based & on caloric intake 90,000 frogs 27,000,000 grasshoppers 1 ton grass 54 humans don't always at of food eat top pyramid eat at of top food pyramid (small communities) 55 56 at people eat as heterotrophs lower level of pyramid 57 Humans and ecological energetics 7.9 billion humans Z secondary consumers Y primary consumers X primary producers An open question: How many humans can the ecosystems of Earth sustain according to ecological energetics? Some ecologists argue Earth can sustain 10 billion people, but only if we eat at lower trophic levels 58 Biomagnification - accumulation of toxic materials as move up Humans produce toxic pyramid substances that do not occur naturally (e.g. > - lots of mercury organochlorides or DDT) eat) and substances in unnaturally high top animals eatove S quantities (e.g. mercury) in food chain high levels of toxins Some of them eat so much accumulate in food chains, producing unexpected effects 59 Biomagnification 60 DDT ends up in Great Lakes d Algae bo : d Polar bears 61 DDE in tissues led to birds laying thin wall eggs d crush eggs and break ↓ O for offspring years ↓ BAD !! 62 Biomagnification High concentrations of DDT lead to near extinction of many hawks and eagles 63 64 65 Summary The sun provides energy for life Autotrophs use non-biological energy to synthesize sugars from carbon dioxide and water; heterotrophs feed on autotrophs Organisms in a food chain show a pyramid-shaped trophic structure Biomagnification occurs when chemicals reach high concentrations in top predators 66
