DOCSLIB.ORG

Ecosystems and Restoration Ecology

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Ecosystems and Restoration Ecology Overview: Cool Ecosystem Chapter 55 • An ecosystem consists of all the organisms living in a community, as well as the abiotic factors with Ecosystems and Restoration which they interact Ecology • Ecosystems range from a microcosm, such as an aquarium, to a large area such as a lake or forest • Ecosystems’ dynamics involve two main processes: energy flow and chemical cycling • Energy flows through ecosystems while matter cycles within them Concept 55.1: Physical laws govern energy Conservation of Energy flow and chemical cycling in ecosystems • Laws of physics and chemistry apply to • Ecologists study the transformations of energy ecosystems, particularly energy flow and matter within their system • The first law of thermodynamics states that energy cannot be created or destroyed, only transformed • Energy enters an ecosystem as solar radiation, is conserved, and is lost from organisms as heat Conservation of Mass • The second law of thermodynamics states that • The law of conservation of mass states that every exchange of energy increases the entropy of matter cannot be created or destroyed the universe • Chemical elements are continually recycled within • In an ecosystem, energy conversions are not ecosystems completely efficient, and some energy is always • In a forest ecosystem, most nutrients enter as dust lost as heat or solutes in rain and are carried away in water • Ecosystems are open systems, absorbing energy and mass and releasing heat and waste products Energy, Mass, and Trophic Levels • Autotrophs build molecules themselves using • Energy and nutrients pass from primary photosynthesis or chemosynthesis as an energy producers (autotrophs) to primary consumers source (herbivores) to secondary consumers • Heterotrophs depend on the biosynthetic output of (carnivores) to tertiary consumers (carnivores other organisms that feed on other carnivores) Figure 55.4 Sun Key Chemical cycling • Detritivores, or decomposers , are consumers Heat Energy flow that derive their energy from detritus , nonliving Primary producers organic matter • Prokaryotes and fungi are important detritivores Primary Detritus • Decomposition connects all trophic levels consumers Secondary and Microorganisms and other tertiary consumers detritivores Concept 55.2: Energy and other limiting Ecosystem Energy Budgets factors control primary production in • The extent of photosynthetic production sets the ecosystems spending limit for an ecosystem’s energy budget • In most ecosystems, primary production is the amount of light energy converted to chemical energy by autotrophs during a given time period • In a few ecosystems, chemoautotrophs are the primary producers The Global Energy Budget Gross and Net Production • The amount of solar radiation reaching the Earth’s • Total primary production is known as the surface limits photosynthetic output of ecosystems ecosystem’s gross primary production (GPP) • Only a small fraction of solar energy actually • GPP is measured as the conversion of chemical strikes photosynthetic organisms, and even less is energy from photosynthesis per unit time of a usable wavelength • Net primary production (NPP) is GPP minus energy used by primary producers for respiration • NPP is expressed as − Energy per unit area per unit time (J/m 2⋅yr), or − Biomass added per unit area per unit time (g/m 2⋅yr) Figure 55.5 TECHNIQUE 80 Snow • NPP is the amount of new biomass added in a Clouds given time period 60 • Only NPP is available to consumers Vegetation • Standing crop is the total biomass of 40 photosynthetic autotrophs at a given time Soil Percentreflectance • Ecosystems vary greatly in NPP and contribution 20 to the total NPP on Earth Liquid water 0 400 600 800 1,000 1,200 Visible Near-infrared Wavelength (nm) Figure 55.6 Net primary production • Tropical rain forests, estuaries, and coral reefs are (kg carbon/m 2....yr) among the most productive ecosystems per unit 3 area • Marine ecosystems are relatively unproductive per 2 unit area, but contribute much to global net primary production because of their volume 1 0 Figure 55.7 • Net ecosystem production (NEP) is a measure Float surfaces of the total biomass accumulation during a given for 6–12 hours period to transmit data to satellite. • NEP is gross primary production minus the total respiration of all organisms (producers and Total cycle time: Float descends 10 days consumers) in an ecosystem to 1,000 m and “parks.” O2 concentration is • NEP is estimated by comparing the net flux of CO 2 recorded as float ascends. and O 2 in an ecosystem, two molecules connected by photosynthesis Drift time: 9 days • The release of O 2 by a system is an indication that it is also storing CO 2 Primary Production in Aquatic Ecosystems Light Limitation • In marine and freshwater ecosystems, both light • Depth of light penetration affects primary and nutrients control primary production production in the photic zone of an ocean or lake Figure 55.8 RESULTS Nutrient Limitation 30 Ammonium enriched • More than light, nutrients limit primary production 24 Phosphate in geographic regions of the ocean and in lakes enriched • A limiting nutrient is the element that must be Unenriched added for production to increase in an area 18 control • Nitrogen and phosphorous are typically the nutrients that most often limit marine production 12 • Nutrient enrichment experiments confirmed that Phytoplankton density nitrogen was limiting phytoplankton growth off (millionsofcells per mL) 6 the shore of Long Island, New York 0 ABCGD E F Collection site • Experiments in the Sargasso Sea in the subtropical Atlantic Ocean showed that iron limited primary production • Upwelling of nutrient-rich waters in parts of the oceans contributes to regions of high primary production • The addition of large amounts of nutrients to lakes has a wide range of ecological impacts Primary Production in Terrestrial Ecosystems • In some areas, sewage runoff has caused eutrophication of lakes, which can lead to loss of • In terrestrial ecosystems, temperature and most fish species moisture affect primary production on a large • In lakes, phosphorus limits cyanobacterial growth scale more often than nitrogen • Primary production increases with moisture • This has led to the use of phosphate-free detergents Nutrient Limitations and Adaptations That Reduce Them • Actual evapotranspiration is the water transpired by plants and evaporated from a landscape • On a more local scale, a soil nutrient is often the • It is affected by precipitation, temperature, and limiting factor in primary production solar energy • In terrestrial ecosystems, nitrogen is the most • It is related to net primary production common limiting nutrient • Phosphorus can also be a limiting nutrient, especially in older soils Concept 55.3: Energy transfer between trophic levels is typically only 10% efficient • Various adaptations help plants access limiting nutrients from soil • Secondary production of an ecosystem is the – Some plants form mutualisms with nitrogen-fixing amount of chemical energy in food converted to bacteria new biomass during a given period of time – Many plants form mutualisms with mycorrhizal fungi; these fungi supply plants with phosphorus and other limiting elements – Roots have root hairs to increase surface area – Many plants release enzymes that increase the availability of limiting nutrients Figure 55.10 Production Efficiency • When a caterpillar feeds on a leaf, only about one-sixth of the leaf’s energy is used for Plant material secondary production eaten by caterpillar • An organism’s production efficiency is the 200 J fraction of energy stored in food that is not used for respiration Production Net secondary production × 100% 67 J Cellular = 100 J respiration efficiency Assimilation of primary production Feces 33 J Not assimilated Growth (new biomass; Assimilated secondary production) Trophic Efficiency and Ecological Pyramids • Birds and mammals have efficiencies in the • Trophic efficiency is the percentage of range of 1 −3% because of the high cost of production transferred from one trophic level to the endothermy next • Fishes have production efficiencies of around • It is usually about 10%, with a range of 5% to 20% 10% • Trophic efficiency is multiplied over the length of a • Insects and microorganisms have efficiencies of food chain 40% or more • Approximately 0.1% of chemical energy fixed by photosynthesis reaches a tertiary consumer • A pyramid of net production represents the loss of • In a biomass pyramid, each tier represents the dry energy with each transfer in a food chain weight of all organisms in one trophic level • Most biomass pyramids show a sharp decrease at successively higher trophic levels Figure 55.12 Trophic level Dry mass (g/m 2) Tertiary consumers 1.5 Secondary consumers 11 • Certain aquatic ecosystems have inverted Primary consumers 37 Primary producers 809 biomass pyramids: producers (phytoplankton) are consumed so quickly that they are outweighed by (a) Most ecosystems (data from a Florida bog) primary consumers • Turnover time is a ratio of the standing crop biomass to production Trophic level Dry mass (g/m 2) Primary consumers (zooplankton) 21 Primary producers (phytoplankton) 4 (b) Some aquatic ecosystems (data from the English Channel) Concept 55.4: Biological and geochemical processes cycle nutrients and water in • Dynamics of energy flow in ecosystems have important implications for the human population ecosystems • Eating meat is a relatively inefficient way of • Life depends on recycling chemical
Load more

Recommended publications
  • Revisiting the Sulfur-Water Chemical System in the Middle Atmosphere of Venus Wencheng Shao, Xi Zhang, Carver Bierson, Therese Encrenaz
    Revisiting the Sulfur-Water Chemical System in the Middle Atmosphere of Venus Wencheng Shao, Xi Zhang, Carver Bierson, Therese Encrenaz To cite this version: Wencheng Shao, Xi Zhang, Carver Bierson, Therese Encrenaz. Revisiting the Sulfur-Water Chemi- cal System in the Middle Atmosphere of Venus. Journal of Geophysical Research. Planets, Wiley- Blackwell, 2020, 125 (8), pp.e06195. 10.1029/2019JE006195. hal-03250477 HAL Id: hal-03250477 https://hal.archives-ouvertes.fr/hal-03250477 Submitted on 11 Jun 2021 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Copyright RESEARCH ARTICLE Revisiting the Sulfur‐Water Chemical System 10.1029/2019JE006195 in the Middle Atmosphere of Venus Key Points: Wencheng D. Shao1 , Xi Zhang1 , Carver J. Bierson1 , and Therese Encrenaz2 • We found that there is no bifurcation behavior in the 1Department of Earth and Planetary Sciences, University of California, Santa Cruz, CA, USA, 2LESIA, Observatoire de sulfur‐water chemical system as previously claimed Paris, PSL University, CNRS, Sorbonne University, University Sorbonne Paris City, Meudon, France • The observed SO2‐H2O anticorrelation can be explained by the sulfur‐water chemistry with Abstract Sulfur‐water chemistry plays an important role in the middle atmosphere of Venus.
    [Show full text]
  • Arxiv:2012.11628V3 [Astro-Ph.EP] 26 Jan 2021
    manuscript submitted to JGR: Planets The Fundamental Connections Between the Solar System and Exoplanetary Science Stephen R. Kane1, Giada N. Arney2, Paul K. Byrne3, Paul A. Dalba1∗, Steven J. Desch4, Jonti Horner5, Noam R. Izenberg6, Kathleen E. Mandt6, Victoria S. Meadows7, Lynnae C. Quick8 1Department of Earth and Planetary Sciences, University of California, Riverside, CA 92521, USA 2Planetary Systems Laboratory, NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA 3Planetary Research Group, Department of Marine, Earth, and Atmospheric Sciences, North Carolina State University, Raleigh, NC 27695, USA 4School of Earth and Space Exploration, Arizona State University, Tempe, AZ 85287, USA 5Centre for Astrophysics, University of Southern Queensland, Toowoomba, QLD 4350, Australia 6Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA 7Department of Astronomy, University of Washington, Seattle, WA 98195, USA 8Planetary Geology, Geophysics and Geochemistry Laboratory, NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA Key Points: • Exoplanetary science is rapidly expanding towards characterization of atmospheres and interiors. • Planetary science has similarly undergone rapid expansion of understanding plan- etary processes and evolution. • Effective studies of exoplanets require models and in-situ data derived from plan- etary science observations and exploration. arXiv:2012.11628v4 [astro-ph.EP] 8 Aug 2021 ∗NSF Astronomy and Astrophysics Postdoctoral Fellow Corresponding author: Stephen R. Kane, [email protected] {1{ manuscript submitted to JGR: Planets Abstract Over the past several decades, thousands of planets have been discovered outside of our Solar System. These planets exhibit enormous diversity, and their large numbers provide a statistical opportunity to place our Solar System within the broader context of planetary structure, atmospheres, architectures, formation, and evolution.
    [Show full text]
  • Discovery of Chemosynthesis-Based Association on the Cretaceous Basal Leatherback Sea Turtle from Japan
    Editors' choice Discovery of chemosynthesis-based association on the Cretaceous basal leatherback sea turtle from Japan ROBERT G. JENKINS, ANDRZEJ KAIM, KEI SATO, KAZUHIRO MORIYA, YOSHINORI HIKIDA, and REN HIRAYAMA Jenkins, R.G., Kaim, A., Sato, K., Moriya, K., Hikida, Y., and Hirayama, R. 2017. Discovery of chemosynthesis-based association on the Cretaceous basal leatherback sea turtle from Japan. Acta Palaeontologica Polonica 62 (4): 683–690. We report a Late Cretaceous chemosynthetic community fueled by decomposing basal leatherback sea turtle on the ocean floor in the western Pacific. The fossil association representing this community has been recovered from the matrix of a concretion containing a single carapace of Mesodermochelys sp. from Late Cretaceous outer shelf to upper slope deposit of northern Hokkaido, Japan. The carapace displays boreholes most likely performed by boring bivalves, and is associated with molluscan shells, mainly Provanna cf. nakagawensis and Thyasira tanabei. Since this association is similar to fauna already known from Late Cretaceous hydrocarbon seeps, sunken wood, and plesiosaur-falls in Hokkaido, it is suggested that all types of chemosynthesis-based communities in the Late Cretaceous of western Pacific may have belonged to the same regional pool of animals and were not yet fully differentiated into three independent types of com- munities as it is known today. This finding also indicates that the sulfophilic stage of the vertebrate-fall communities was supported not only by plesiosaur carcasses, which were previously reported, but also by sea turtle carcasses. It highlights the possibility of surviving vertebrate-fall communities through the end-Cretaceous mass extinction event on carcasses of sea turtles which are the only large marine vertebrates surviving this event.
    [Show full text]
  • Chapter 5 Hmdscience.Com EN Online Vir Onmental Science Work Ecosystems How
    DO NOT EDIT--Changes must be made through “File info” printcode=a Chapter 5 Section 1 Energy Flow in Ecosystems How Section 2 The Cycling of Matter Section 3 How Ecosystems Change Why It Matters Ecosystems This frog gets the energy it needs to survive by eating other organisms, such as damselflies. Frogs and damselflies are both consumers in an aquatic food chain. Work How does energy continue to be transferred in this food chain? CASESTUDY Learn how pollutants, like the pesticide DDT, are transferred through a food chain in the case study DDT in an Aquatic Food Chain on page 120. Online enVirOnmental Science HMDScience.com Go online to access additional resources, including labs, worksheets, multimedia, and resources in Spanish. Inc. Cosmos Blank/Photo Researchers, ©A. 116 DO NOT EDIT--Changes must be made through “File info” printcode=a Section 1 Energy Flow in Objectives Describe how energy is transferred from the sun Ecosystems to producers and then to consumers. organisms need energy to survive, grow, and reproduce. Different organisms Describe one way in which get energy from different sources, but the ultimate source of energy for almost all consumers depend on producers. organisms on earth is the sun. Identify two types of consumers. Explain how energy transfer in a Life Depends on the Sun food web is more complex than Energy from the sun enters an ecosystem when organisms use sunlight energy transfer in a food chain. to make sugar in a process called photosynthesis. During photosynthesis, plants, algae, and some bacteria capture light energy from the sun and Explain why an energy pyramid use it to convert carbon dioxide and water into sugar and oxygen, as is a representation of trophic shown in Figure 1.1.
    [Show full text]
  • Chemosynthesis: What It We Can Learn from Hydrothermal Vents
    Chemosynthesis:Chemosynthesis: WhatWhat itit wewe cancan learnlearn fromfrom hydrothermalhydrothermal ventsvents Ryan Perry Geol 062 II.. IInnttrroo ttoo MMeettaabboolliissmm 1. CCaarrbboonn fifixxaattiioonn aanndd PPhhoottoossyynntthheessiiss 2. FFaammiilliiaarr ooxxiiddaattiivvee mmeettaabboolliissmm 3. OOxxyyggeenniicc PPhhoottoossyynntthh.. 4. GGeeoollooggiicc ccoonnsseeqquueenncceess IIII.. CChheemmoossyynntthheessiiss 1. HHyyddrrootthheerrmmaall VVeennttss 2. AArrcchheeaann 3. CChheemmoossyynntthheettiicc mmeettaabboolliissmm:: MMiiccrroobbeess RRuullee!!!!!! 4. CChheemmoossyynntthheettiicc eeccoossyysstteemmss IIIIII.. WWhhyy aarree eexxttrreemmoopphhiilleess ssoo ccooooll?? 1. BBiioommeeddiiccaall 2. IInndduussttrriiaall 3. WWhhaatt eexxttrreemmoopphhiilleess tteeaacchh uuss aabboouutt eeaarrllyy lliiffee 4. EExxoobbiioollooggyy IIVV.. EExxoobbiioollooggyy PPrreebbiioottiicc CChheemmiissttrryy oonn EEaarrtthh PPoossssiibbllee ((pprroobbaabbllee??)) oorriiggiinnss ooff lliiffee.. PPoossssiibbiillee lliiffee eellsseewwhheerree iinn tthhee ssoollaarr ssyysstteemm.. MMeettaabboolliissmm • The complete set of chemical reactions that take place within a cell. • Basis of all life processes. • Catabolic and Anabolic MMeettaabboolliissmm • CCaattaabbllooiicc mmeettaabboolliissmm---- hhiigghh eenneerrggyy mmoolleeccuulleess ((eelleeccttrroonn--ddoonnoorrss,, ffoooodd)) aarree ooxxiiddiizzeedd,, hhaavviinngg tthheeiirr eelleeccttrroonnss ttrraannssffeerrrreedd ttoo aann eelleeccttrroonn--aacccceeppttoorr.. • EElleeccttrroonn ppaasssseess ddoowwnn
    [Show full text]
  • The Chemosynthetic Cafe
    ocean INSPIRE: Chile Margin 2010 The Chemosynthetic Cafe www.oceanexplorer.noaa.gov Focus Chemosynthesis in hydrothermal vent ecosystems Grade Level 9-12 (Biology/Chemistry) Focus Question How is energy obtained and transferred in photosynthesis and chemosynthesis, and how are these processes similar and different? Learning Objectives n Students will compare and contrast photosynthesis and chemosynthesis. n Students will define oxidation and reduction as these terms apply to electron transfer. n Students will explain the overall process by which energy is captured and transferred during photosynthesis and chemosynthesis. Materials q None Audio-Visual Materials q (Optional) video or computer projection equipment to show images from the INSPIRE: Chile Margin 2010 Web page (http:// oceanexplorer.noaa.gov/explorations/10chile/welcome.html) Teaching Time Two 45-minute class periods, plus time for student assignments Seating Arrangement Groups of 3-4 students Maximum Number of Students 32 Image captions/credits on Page 2. Key Words Hydrothermal vent Autotroph Photosynthesis 1 www.oceanexplorer.noaa.gov INSPIRE: Chile Margin 2010: The Chemosynthetic Cafe Grades 9-12 (Biology/Chemistry) Chemosynthesis Electron transport Chile Triple Junction Background Information NOTE: Explanations and procedures in this lesson are written at a level appropriate to professional educators. In presenting and discussing this material with students, educators may need to adapt the language and instructional approach to styles that are best suited to specific student groups. Earthquakes and volcanoes are among Earth’s most spectacular and terrifying geological events. The Mount St. Helens eruption of 1980 Images from Page 1 top to bottom: Map of the Southeast Pacific Ocean and South and the Haiti (7.0 magnitude) and Chile (8.8 magnitude) earthquakes American continent showing the Chile Rise spreading center, the Peru-Chile Margin, and of 2010 are recent and memorable examples of the extreme power the location of the Chile Triple Junction.
    [Show full text]
  • Chemosynthesis for the Classroom (Adapted from the Expedition to the Deep Slope 2006)
    o c e a n Expl ration & Research Lessons from the Deep: Exploring the Gulf of Mexico’s Deep-Sea Ecosystems Education Materials Collection Chemosynthesis for the Classroom (adapted from the Expedition to the Deep Slope 2006) Focus Chemosynthetic bacteria Grade Level 9-12 (Chemistry/Biology) Focus Question What changes affect succession in the development of chemosynthetic bacterial communities? Learning Objectives m Students will observe the development of chemosynthetic bacterial communities. m Students will recognize that organisms modify their environment in ways that create opportunities for other organisms to thrive. m Students will be able to explain the process of chemosynthesis. m Students will be able to explain the relevance of chemosynthesis to biological communities in the vicinity of cold seeps. Materials m Directions for Setting Up Winogradsky Columns, one copy for each student group Materials for Winogradsky columns for each student group: m 2 1-liter plastic soda bottles m 1 Liter black mud from a local river, lake, or estuary m 1 Liter water from each mud/sand location used Image captions/credits on Page 2. m 1 Small bucket m 1 500 ml plastic beaker m 1 Paint stirrer or large spoon m 1 Sheet of newspaper 1 www.oceanexplorer.noaa.gov Lessons from the Deep: Exploring the Gulf of Mexico’s Deep-Sea Ecosystems Chemosysthesis for the Classroom - Grades 9-12 (Chemistry/Biology) m 1 Tablespoon powdered chalk (see Learning Procedure, Step 1d) m 1 Crushed multivitamin pill m Calcium sulfate (Plaster of Paris), approximately 80 g
    [Show full text]
  • Chapter 13 Lecture
    ChapterChapter 1 13 Clickers Lecture Essentials of Oceanography Eleventh Edition Biological Productivity and Energy Transfer Alan P. Trujillo Harold V. Thurman © 2014 Pearson Education, Inc. Chapter Overview • Primary productivity is photosynthesis. • Productivity is globally and seasonally variable. • Feeding relationships are represented by food chains and food webs. • Oceans are being overfished. © 2014 Pearson Education, Inc. Primary Productivity • Rate at which energy is stored in organic matter – Photosynthesis uses solar radiation. – Chemosynthesis uses chemical reactions. • 99.9% of the ocean’s biomass relies directly or indirectly on photosynthesis for food. © 2014 Pearson Education, Inc. Photosynthesis © 2014 Pearson Education, Inc. Measurement of Primary Productivity • Directly – capture plankton in plankton nets • Measure radioactive carbon in seawater © 2014 Pearson Education, Inc. Measurement of Primary Productivity • Monitor ocean color with satellites – Photosynthetic phytoplankton use green pigment chlorophyll • SeaWiFS (Sea-viewing Wide Field of View Sensor) satellite sensor collected ocean color data 1997–2010 • MODIS (Moderate Resolution Imaging Spectroradiometer) – current – Measures 36 spectral frequencies © 2014 Pearson Education, Inc. Factors Affecting Primary Productivity • Nutrient availability – Nitrate, phosphorous, iron, silica – Most from river runoff – Productivity high along continental margins – Redfield ratio – C:N:P © 2014 Pearson Education, Inc. Factors Affecting Primary Productivity • Solar radiation – Uppermost surface seawater and shallow seafloor – Compensation depth – net photosynthesis becomes zero – Euphotic zone —from surface to about 100 meters (330 feet) • Enough light for photosynthesis © 2014 Pearson Education, Inc. Light Transmission in Ocean Water • Visible light portion of the electromagnetic spectrum • Blue wavelengths penetrate deepest • Longer wavelengths (red, orange) absorbed first © 2014 Pearson Education, Inc. Transmission of Light in Seawater © 2014 Pearson Education, Inc.
    [Show full text]
  • Ocean Primary Production
    Learning Ocean Science through Ocean Exploration Section 6 Ocean Primary Production Photosynthesis very ecosystem requires an input of energy. The Esource varies with the system. In the majority of ocean ecosystems the source of energy is sunlight that drives photosynthesis done by micro- (phytoplankton) or macro- (seaweeds) algae, green plants, or photosynthetic blue-green or purple bacteria. These organisms produce ecosystem food that supports the food chain, hence they are referred to as primary producers. The balanced equation for photosynthesis that is correct, but seldom used, is 6CO2 + 12H2O = C6H12O6 + 6H2O + 6O2. Water appears on both sides of the equation because the water molecule is split, and new water molecules are made in the process. When the correct equation for photosynthe- sis is used, it is easier to see the similarities with chemo- synthesis in which water is also a product. Systems Lacking There are some ecosystems that depend on primary Primary Producers production from other ecosystems. Many streams have few primary producers and are dependent on the leaves from surrounding forests as a source of food that supports the stream food chain. Snow fields in the high mountains and sand dunes in the desert depend on food blown in from areas that support primary production. The oceans below the photic zone are a vast space, largely dependent on food from photosynthetic primary producers living in the sunlit waters above. Food sinks to the bottom in the form of dead organisms and bacteria. It is as small as marine snow—tiny clumps of bacteria and decomposing microalgae—and as large as an occasional bonanza—a dead whale.
    [Show full text]
  • 1 Students Will Grow and Observe Succession and Chemosynthesis Of
    GROWING CHEMOSYNTHETIC BACTERIA OVERVIEW Students will grow and observe succession and chemosynthesis of bacterial colonies: one lighted, the other in the dark. This activity uses the concepts of the Winogradsky column, a device which enriches and isolates certain organisms involved in the sulfur and nitrogen cycles. The activity provides a rough analog to both processes of chemosynthesis and succession; processes which occur at deep sea hydro- thermal vents and form the base of the food chain in the absence of sunlight. (Note that the original Winogradsky column was made by a Russian microbiologist Sergei N. Winogradsky.) CONCEPTS • Some organisms cannot draw energy from the Sun and must find other energy sources to live. • Both photosynthesis (uses sunlight) and chemosynthesis are means of producing sugar (stored chemical energy) • Photosynthetic organisms use light as their energy source; chemosynthetic organisms use chemi- cals. The result for both organisms is the same: energy. The by-products are different, however. In photosynthesis, oxygen is given off as a waste product. In chemosynthesis sulfate is given off. • As organisms thrive in a given environment their by-products create a new environment where new species thrive. This is called succession. MATERIALS For each group: • Black mud (enough to fill the graduated cylinders). See Preparation section. • 80 g of CaSO4 (Plaster of Paris: found in any hardware store) • 20 Jars or beakers for mixing • Stirring rods • Organic straw or filter paper bits. (Tear strips of lab filter paper) • 3 Liters (about 3 quarts) of pond, salty sea water or swamp water • 4 Grams baking soda • 20 Multivitamin pills and something with which to crush them • Plastic wrap • Rubber bands • A light source that can stay on for six weeks or longer • Tape and markers for labeling columns • Flashlight with red cellophane on lighted end (can be attached with rubber band) • Two 500 milliliter graduated cylinders or columns PREPARATION Divide the class into pairs or small groups.
    [Show full text]
  • Marine Science Marine
    We are working with Cambridge International towards endorsement of this title. AS & A Level Marine Science COURSEBOOK Marine Science for Cambridge International AS & A Level COURSEBOOK Matthew Parkin, Melissa Lorenz, Claire Brown & Jules Robson Completely Cambridge Cambridge University Press works with Cambridge Assessment International Education and experienced authors to produce high-quality endorsed textbooks and digital resources that support Cambridge Teachers and encourage Cambridge Learners worldwide. To nd out more about Cambridge University Press visit cambridge.org/cambridge-international DRAFT Second edition Cambridge Elevate edition Original material © Cambridge University Press 2019. This material is not final and is subject to further changes prior to publication. We are working with Cambridge International towards endorsement of this title. Contents Contents How to use this series 00 Practical skills 1 Experimental planning including making How to use this book 00 estimates, predictions and hypotheses 00 Introduction 00 2 Presentation of data and observations 00 3 Evaluation of procedures and data 00 Introduction to command words 00 4 Analysis of data and conclusions 00 1 Water 6 Physiology of marine organisms 1.1 Particle theory and bonding 00 6.1 General cell structure 00 1.2 Solubility in water 00 6.2 Movement of substances 00 1.3 Density and pressure 00 6.3 Gas exchange 00 2 Earth processes 6.4 Osmoregulation 00 2.1 Tectonic processes 00 7 Energy 2.2 Weathering, erosion and sedimentation 00 7.1 Photosynthesis 00 2.3
    [Show full text]
  • AST-2017-1693-Ver9-Rushby 4P 469..480
    Long-Term Planetary Habitability and the Carbonate-Silicate Cycle Andrew J. Rushby,1,2 Martin Johnson,2,3 Benjamin J.W. Mills,4 Andrew J. Watson,5 and Mark W. Claire6,7,8 Abstract The potential habitability of an exoplanet is traditionally assessed by determining whether its orbit falls within the circumstellar ‘‘habitable zone’’ of its star, defined as the distance at which water could be liquid on the surface of a planet (Kopparapu et al., 2013). Traditionally, these limits are determined by radiative-convective climate models, which are used to predict surface temperatures at user-specified levels of greenhouse gases. This approach ignores the vital question of the (bio)geochemical plausibility of the proposed chemical abundances. Carbon dioxide is the most important greenhouse gas in Earth’s atmosphere in terms of regulating planetary temperature, with the long- term concentration controlled by the balance between volcanic outgassing and the sequestration of CO2 via chemical weathering and sedimentation, as modulated by ocean chemistry, circulation, and biological (microbial) productivity. We developed a model that incorporates key aspects of Earth’s short- and long-term biogeochemical carbon cycle to explore the potential changes in the CO2 greenhouse due to variance in planet size and stellar insolation. We find that proposed changes in global topography, tectonics, and the hydrological cycle on larger planets result in proportionally greater surface temperatures for a given incident flux. For planets between 0.5 and 2 R4, the effect of these changes results in average global surface temperature deviations of up to 20 K, which suggests that these relationships must be considered in future studies of planetary habitability.
    [Show full text]