Communities and Ecosystems: Energy Flow and Trophic Relationships in Biology

Ecosystems and Ecological Networks

MSc. Tania Kobelkowsky VidrioEcosystems and ecological networks (video) · https://www.khanacademy.org/science/biology/ecology/community-structure- and-diversity/v/biodiversity-ecosystems-and-ecological-networksCONCEPTSSpecies Group of organisms sharing common characteristics, that can interbreed and reproduce fertile offspring. (offspring that can interbreed and also produce young) @PIOTR NASKRECKI 201 Environment in which a species normally lives

Habitat and Species Interaction

HabitatSpecies Group of different species (populations) living and interacting with each other in a common habitat (only biotic components) An ecosystem is a biological community (biotic components) interacting with the physical environment (abiotic components)Organisms of the same species Species Population Community Group of different species (populations) living and interacting with each other in a common habitat (only biotic components) Collection of ecosystems Ecosystem Biome Biosphere An ecosystem is a biological community (biotic components) interacting with the physical environment (abiotic components)900

Global Atmospheric Circulation

60° Easterlies Polar Front Warmer air rises Low Pressure 30º Westerlies Air descends High Pressure Horse Latitudes NE Trade Winds 00 Equatorial Doldrums Warm air ri! Low Presst SE Trade Winds Horse Latitudes 300 Westerlies Air descends High Pressure 600 Easterlies Polar Front Warmer air rises Low Pressure 0

Abiotic and Biotic Factors

Abiotic factors JAN October September November August December Northern Autumn / Southern Spring Northern Winter Southern Summer Sun Northern Summer Southern Winter Northern Spring / Southern Autumn June January February May March April Average monthly temperature(ºC) by FAO - SDRN - Agrometeorology Group - 1997 -29.5-14.5 -4.5 5.5 15.5 30.5 40 July Biotic factorsniche Moisture Temperature Slope Ecological niche?Ecological niche Set of environmental conditions under which the populations of a species can survive indefinitely without the need for immigration. - 18 Feeding height (meters) +6 O # 12 Cape May Warbler Feeds at the tips of branches near the top of the tree Bay-Breasted Warbler Feeds in the middle part of the tree Spruce tree Yellow-Rumped Warbler Feeds in the lower part of the tree and at the bases of the middle branches Moisture Temperature Slope

Sources of Energy for the Ecosystem

https://youtu.be/eo5XndJaz-Y BEFORE we talk about Feeding relationships Control of flow of energy through ecosystems ...

Photosynthesis and Respiration

Photosynthesis & RespirationCarbon dioxide Water Light energy Plant ( photosynthesis) Oxygen Glucose Chemical energy Inputs Outputs sunlight plant cell chloroplast CO2 is taken in by plant leaves PHOTOSYNTHESIS carbon dioxide and water glucose and oxygen 02 is given out heat mitochondria animal cell CELLULAR RESPIRATION ATP H2O is taken up from the soil by plant roots @Sheri Amsel www.exploringnature.org Carbon dioxide + Water Light Chlorophyll › Glucose + Oxygen Glucose is produced and is stored as starch Photosynthesis Energy from sunlight is trapped by chlorophyll in green leaves-120 -60 0 60 120 60 60 1 0 D 0 -60 -60 -120 -60 0 60 120 0 2 4 6 8 10 12 14 16 18 Figure 1. Ultraviolet Radiation Index Across the World.Respiration plant cell sunlight chloroplast L PHOTOSYNTHESIS carbon dioxide and water glucose and oxygen heat mitochondria animal cell CELLULAR RESPIRATION ATP @Sheri Amsel www.exploringnature.org Glucose + Oxygen Oxidation Carbon dioxide + Water +Energy Oxidation C6H 2 O2 + 602 6CO2 + 6H2O + ATP Carbon dioxide Water Energy Outputs Inputs Oxygen Glucose Organisms (oxidation)

Energy Flow in an Ecosystem

IN AN ECOSYSTEM WHERE DOES THE ENERGY GO?WHERE DOES THE ENERGY GO? Autotrophs Heterotrophs Producer Herbivore (primary consumer) Carnivore (secondary consumer) Energy Light Chemical elements photosynthesis H C TC D Detritus cellular respiration Decomposer Inorganic compounds (chemical elements) "TODOS ESTAMOS CONECTADOS EN EL GRAN CICLO DE LA VIDA." solar energy

Feeding Relationships

• Producers Convert abiotic components into living matter [autotrophs].
• Consumers Constant input of energy and new biological matter into the ecosystem.
• Decomposers Eat other organisms to obtain energy and matter (minerals and nutrients) [heterotrophs]. (Herbivores and carnivores) Pass energy and biomass from producers to consumers. Consumers Food and nutrients from the breakdown of dead organic matter -> releasing nutrients for ready absorption by producers. Build-up of humus (organic material) in soil, improving ability of soil to retain nutrients. Producers Essential for cycling of matter in ecosystems (including carbon and nitrogen) ~~ Decomposers

Trophic Levels and Food Chains

WHERE DOES THE ENERGY GO? Trophic levels Position of an organism in a food chain > Food chains Shows the flow of energy and matter between organisms Western wheat grass Club-horned grasshopper Great Plains toad Garter snake Swainson's hawk Trophic levels -> producer primary consumer secondary consumer tertiary consumer quaternary consumer autotroph herbivore omnivore/carnivore carnivore carnivore The first trophic level, the autotrophs (producers) support the energy requirements of all the other trophic levels above.

Models of Energy Flow

Food Chain and Ecological Pyramid

MODELS OF ENERGY FLOW Western wheat grass Club-horned grasshopper Great Plains toad Garter snake Swainson's hawk FOOD CHAIN * producer primary consumer secondary consumer tertiary consumer quaternary consumer autotroph herbivore omnivore/carnivore carnivore carnivore Hawk Fourth trophic level Tertiary ₼ consumer Carnivore Snake Secondary consumer Third trophic level Carnivore Primary consumer Decomposer Second trophic level Herbivore Mouse Grass First trophic level Producer ECOLOGICAL PYRAMID * * Trophic levels

Food Web

FOOD WEB Smaller toothed whales Sperm whale Baleen whale Leopard seal Elephant seal Penguins Other birds Squid Other ? seals Fish Krill Other herbivorous zooplankton Carnivorous zooplankton Phytoplankton

Loss of Energy

LOSS OF ENERGY !!! Algae and cyanobacteria Small heterotrophs Trout Smelt 1000 calories Human 150 calories 1.2 calories 30 calories 6 caloriessolar energy photosynthesis H C TC D cellular respiration 2nd Law of Thermodynamics Transformations of energy are inefficient , energy is lost at each stage as heat .990 Joules energy lost to environment 1000 Joules of Light Energy 10 Joules 1 Joules Energy Energy 10 Joules energy available as food (Producer) 1 Joule energy available as food (Herbivore) 0.1 Joule energy available as food (Carnivore) Progressive Loss of Energy in Food Chain Waste & dead matter 2 kcal/m2/yr Heat Quaternary consumers 20 kcal/m2/yr Heat Tertiary consumers Heat 200 kcal/m2/yr Heat Secondary consumers 2,000 kcal/m2/yr DECOMPOSERS F Heat Primary consumers F 20,000 kcal/m2/yr Primary producers 1 Light energy Law of the 10% Only 10% of the energy is passed from one trophic level to the next 9 Joules energy lost to environment 0.9 Joule energy lost to environment HOW MUCH ENERGY IS LOST? - > 90% Heat

Biotic Relationships

Interaction Types

Biotic relationships Interaction Species A Species B Competition Harmed Harmed Predation Receives benefit Harmed Herbivory Receives benefit Harmed Symbiosis: Parasitism Receives benefit Harmed Commensalism Receives benefit Not affected Mutualism Receives benefit Receives benefit Mutualism interspecific intraspecific Competition Competition Predation Herbivory Commensalism Parasitism