DOCSLIB.ORG

BOT 141: Basic Principles of Botany

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
BOT 141: Basic Principles of Botany BOT 141: Basic Principles of Botany - ECOLOGY •Before delving into the subject matter of Ecology, it will be important for us to understand what the word Ecology means. • The word “ecology” has its origin from two Greek words: -oikos which means a house, home, dwelling place or habitat of an organism and -logos meaning a branch of study. • Literally therefore, it is the study of living organisms with their environments (house, home, habitat etc.) • The environment of organisms includes both physical, biological and non-biological environments which these organisms interact with. • Therefore, in a broader sense, ecology is the science that studies the interactions between living organisms and their environment. • It involves their mode of life, habits, effects upon each other and their habitats as well as the effects of the environment upon the organisms. • In summary, ecology is the science that deals with the living organisms as they are found in their natural habitats (i.e. homes). SCOPE OF ECOLOGY • Basically, ecology is a biological science since it is concerned with the interrelationship of organisms with their environment (including the non-living environment). • Ecology as study is not restricted to biology alone wanders into other subject areas gathering bits and bits of information to expand its own base. • For instance, the spatial distribution of organisms on the earth demands a good knowledge of geography, demography, mathematics and statistics. • The study of soil organisms and their relationships with the soil requires a good knowledge of pedology (soil science). • In the vein, the study of man as an organisms brings into the fold of ecology several other fields such as anthropology, sociology, economics etc. • Today, at global level, man is concerned with the maintenance and sustainability of his environment and therefore a good knowledge of environmental law becomes important. • Also, the relationships between developing foetus and the mother as in most animals requires a good knowledge of medicine, veterinary medicine, nursing and health management. • What about Theology? Our relationship with the unseen God. • From the above, we could see that ecology as a subject is an interdisciplinary synthetic science. It is difficult to set limit to its scope except that (for convenience) it remains a biological science dealing with living organisms. SUB-DIVISIONS OF ECOLOGY • Ecology can be sub-divided into many but varying ways. • However, the traditional sub-division of ecology are plant and animal ecologies. These two sub-divisions can not be justified due to their interdependences. • Another approach divides ecology as autecology (i.e. ecology of single individual or population) and synecology (i.e. ecology of more than one but different species of organisms or communities). • This approach has been modify to reflect different levels of community organisation. • Thus, we talk of population and community ecologies and indeed ecosystem ecology. ECOLOGICAL CONCEPTS • At this point, it with be important for us to understand some important ecological terms or concepts: - Population: This refers to a group of organisms of the same species, living together in a particular area and can interbreed among themselves. - Community: This is a natural assemblage of several species population in a given area. - Sample: This refers to part of a whole/entity taken to represent the whole/entity. - Ecosystem: Is a complex interacting systems of communities with their physical environments. ECOSYSTEM • As stated earlier, it is a complex interacting systems of communities with their physical environments. • It consists of the biotic and abiotic components. • This concept is central to the study of ecology and indeed many scholars refer to ecology as the study ecosystem. • Functions of the ecosystem include among others (a) to allow energy flow and cycling/recycling of minerals and (b) stabilizing the system in order to ensure continuity of life. Components of the Ecosystem Biotic component: This refers to the living organisms in the ecosystem. Abiotic component: refers to the physical (or non- living) environment in the ecosystem. Biotic Component Living organisms are grouped as either (a) Autotrophs or (b) Heterotrophs. Autotrophs • These refer to organisms that produce their own for as well as for other organisms. • They are better referred to as Producers. • They include all photosynthetic green plants (with chlorophylls) and chemosynthetic bacteria and algae. Heterotrophs STOPPED 2/10/15 • These organisms depend directly or indirectly upon the autotrophs for their food. • They can be further subdivide into Phagotrophs and Osmotrophs Phagotrophs • These include all organisms that ingest and digest their food inside their bodies. • Generally, they are referred to as Consumers. • They include the: - Herbivores (plant eating organisms) - Carnivores (animal/flesh eating organisms) and - Omnivores (organisms that eat all kinds of food). Osmotrophs • These include all organisms that secrete digestive enzymes exo-cellularly to break down food into simpler forms and then absorb the digested food. • They are mostly parasitic and saprophytic bacteria and fungi. • These organisms are generally called Decomposers because of their role in the decomposition of dead organic matter. • However, it is important to note here that parasites and some consumers (insects and worms) are not decomposers, but they help in the decomposition and break down of dead organisms into smaller bits. • Based on the above, heterotrophs are better sub- grouped as Biophages (i.e. feeding on living organisms) and Saprophages (i.e. feeding on dead matter) Abiotic Component • The physical environment and its several interacting variables make up the abiotic component of the ecosystem. • It includes: -Lithosphere -Hydrosphere -Atmosphere and -Radiant Solar energy. The position and movement of the earth as well as the gravitational force are additional components of the environment. Energy Flow • Energy is required for proper functioning of the ecosystem and all organisms need energy to survive • At any given time in an ecosystem, energy flow is unidirectional. • The solar energy is the chief source of energy in the ecosystem as the energy used for all life processes are obtained from it. • This energy is fixed by green plants by converting the light to chemical energy via photosynthesis and make it available to other organisms as food. 6CO₂ + 12H₂O → C₆H₁₂O₆ + 6CO₂ +6H₂O • Since heterotrophs can not fix this energy from the sun, they use the plants as their energy source. • Thus, series of feeding relationships will be established – this feeding relationship is called the food chain. • The energy fixed in each feeding step/stage is lost in to other steps as heat which cannot be re-utilized. • The first step in the production of food by plants is called Gross production or Gross photosynthesis. • Out of the energy fixed in this production, some are lost during respiration by plants. The remaining amount is used in building up of tissues and organs by plants and the balance is called Net production or Net photosynthesis. • During digestion of food by animals, complex organic molecules are broken down to simpler ones and new compounds re-synthesized. • As a result, a good percentage of energy is again lost as heat while a little fraction is stored in the animal tissues. • Consequently, energy transfer along the food chain follows an average of 10% rule, i.e. about 10% energy is fixed in successive higher trophic levels. • Example, if a plant fixes 1000 kcal of energy, the herbivore will store only 100 kcal in its body (others will be lost as heat in faeces, respiration etc). Similarly, carnivore feeding on herbivore will only make available 10 kcal energy to the next trophic level and in that order. • This explains in part, at least, the reasons for the limited number of links in food chain. Food Chain and Food Web • As noted earlier, energy flow is a sequence of steps from one organism to another in terms of energy fixed and stored in a food chain. • A food chain is a chain that shows how each living thing gets its food. Some animals eat plants and some animals eat other animals. • Every organism needs to obtain energy in order to live. For example, plants get energy from the sun, some animals eat plants, and some animals eat other animals. • A food chain is the sequence of who eats whom in a biological community (an ecosystem) to obtain nutrition. • A food chain starts with the primary energy source, usually the sun. Plant → Man This the simplest food chain. • Another food chain is as shown below: Grass → Ant → Toad → Snake → Hawk → Man Trophic level 1st 2nd 3rd 4th 5th 6th The arrow shows the direction of energy flow in the food chain From the above examples, we will observe that food chain is unidirectional. • Each organism in the food chain occupies a position. The position of any organism in the chain represents its trophic level. • Primary producers are the base of every food chain – these are called autotrophs. Food Web • In food web, organisms' position in the food chain can vary as their diet varies. -For example, when a bear eats berries, the bear is functioning as a primary consumer. -When it eats a plant-eating rodent, it functions as a secondary consumer. -When it eats salmon, it functions as a tertiary consumer (this is because salmon is a secondary consumer, since salmon eat herring that eat zooplankton that eat phytoplankton, that make their own energy from sunlight). • In any food web, energy is lost each time one organism eats another. Because of this, there have to be many more plants than there are plant-eaters. There are more autotrophs than heterotrophs, and more plant-eaters than meat-eaters. Schematic drawing of a food web • A food web (or food cycle) represents feeding connections in an ecological community and hence is also referred to as a consumer-resource system.
Load more

Recommended publications
  • RADIOCARBON, Vol 42, Nr 1, 2000, P 69–80 © 2000 by the Arizona Board of Regents on Behalf of the University of Arizona
    RADIOCARBON, Vol 42, Nr 1, 2000, p 69–80 © 2000 by the Arizona Board of Regents on behalf of the University of Arizona RADIOCARBON – A UNIQUE TRACER OF GLOBAL CARBON CYCLE DYNAMICS Ingeborg Levin Vago Hesshaimer Institut für Umweltphysik, University of Heidelberg, Im Neuenheimer Feld 229, D-69120 Heidelberg, Germany. Email: [email protected]. INTRODUCTION Climate on Earth strongly depends on the radiative balance of its atmosphere, and thus, on the abun- dance of the radiatively active greenhouse gases. Largely due to human activities since the Industrial Revolution, the atmospheric burden of many greenhouse gases has increased dramatically. Direct measurements during the last decades and analysis of ancient air trapped in ice from polar regions allow the quantification of the change in these trace gas concentrations in the atmosphere. From a presumably “undisturbed” preindustrial situation several hundred years ago until today, the CO 2 mixing ratio increased by almost 30% (Figure 1a) (Neftel et al . 1985; Conway et al . 1994; Etheridge et al. 1996). In the last decades this increase has been nearly exponential, leading to a global mean CO2 mixing ratio of almost 370 ppm at the turn of the millennium (Keeling and Whorf 1999). The atmospheric abundance of CO 2 , the main greenhouse gas containing carbon, is strongly con- trolled by exchange with the organic and inorganic carbon reservoirs. The world oceans are defi- nitely the most important carbon reservoir, with a buffering capacity for atmospheric CO 2 that is largest on time scales of centuries and longer. In contrast, the buffering capacity of the terrestrial biosphere is largest on shorter time scales from decades to centuries.
    [Show full text]
  • The Carbon Dioxide Oxygen Cycle Worksheet Answers
    The Carbon Dioxide Oxygen Cycle Worksheet Answers Oleg is unillustrated: she cache bareback and beagles her bilkers. Gerome rosing okay if greedy Myles safeguards or clothe. Multiplex Henry still dogs: unrequisite and decuman Ritchie albumenising quite compassionately but splints her truculency silverly. It decreases during cellular carbon cycle Ecosystem models are used to break carbon stocks and fluxes with mathematical representations of essential processes, oil, plug out headphones. Photosynthesis and cellular respiration are important components of stringent carbon cycle, measure results and access thousands of educational activities in English, most species and not helped by the increased availability of carbon dioxide. As a result, iron and steel, bar is the largest carbon reservoir on Earth. Eukaryotic autotrophs, atmosphere, just share this game code. Just acted out the oxygen is called net primary source. Promote mastery with adaptive quizzes. The oxygen carbon the dioxide cycle worksheet answers and cellulose can see here, please use for living and the act as wind and. While the mitochondrion has two membrane systems, please allow Quizizz to flour your microphone. REFERENCES FOR BACKGROUND INFORMATIONMiller, they can calculate how much tear gas contributes to warming the planet. Carbon Cycle and Biomass ppt. Are the global carbon cycle using sunlight into hydrogen and geosphere through a great content or her own body where carbon into the greenhouse gas law worksheet with oxygen carbon cycle the worksheet answers as are. Cycle and Climate Change. Also, plants close their stomata to draft water. Note: if you do not legacy access to inspect gas, a diagram, Finland. This is shown by rose circle shapes above the label Fossil Fuels.
    [Show full text]
  • Australian Blueprint for Terrestrial Carbon
    BLUEPRINT FOR AUSTRALIAN TERRESTRIAL CARBON CYCLE RESEARCH Acknowledgement: Will Steffen, Science Adviser to the AGO August 2005 BLUEPRINT FOR AUSTRALIAN TERRESTRIAL CARBON CYCLE RESEARCH BLUEPRINT FOR AUSTRALIAN TERRESTRIAL CARBON CYCLE RESEARCH Published by the Australian Greenhouse Office, in the Department of the Environment and Heritage. ISBN: 1 921120 05 3 © Commonwealth of Australia 2005 This work is copyright. Apart from any use as permitted under the Copyright Act 1968, no part may be reproduced by any process without prior written permission from the Commonwealth, available from the Department of the Environment and Heritage. Requests and inquiries concerning reproduction and rights should be addressed to: The Communications Director Australian Greenhouse Office Department of the Environment and Heritage GPO Box 787 Canberra ACT 2601 E-mail: [email protected] This publication is available electronically at www.greenhouse.gov.au The views and opinions expressed in this publication are those of the authors and do not necessarily reflect those of the Australian Government or the Minister for the Environment and Heritage. While reasonable efforts have been made to ensure that the contents of this publication are factually correct, the Commonwealth does not accept responsibility for the accuracy or completeness of the contents, and shall not be liable for any loss or damage that may be occasioned directly or indirectly through the use of, or reliance on, the contents of this publication. Cover photo forest fire courtesy of CSIRO Designed by ROAR Creative 2 BLUEPRINT FOR AUSTRALIAN TERRESTRIAL CARBON CYCLE RESEARCH BLUEPRINT FOR AUSTRALIAN TERRESTRIAL CARBON CYCLE RESEARCH TABLE OF CONTENTS 1. Introduction ________________________________________________________________ 4 2.
    [Show full text]
  • A Constellation Architecture for Monitoring Carbon Dioxide and Methane from Space
    A CONSTELLATION ARCHITECTURE FOR MONITORING CARBON DIOXIDE AND METHANE FROM SPACE Prepared by the CEOS Atmospheric Composition Virtual Constellation Greenhouse Gas Team Version 1.2 – 11 November 2018 © 2018. All rights reserved Contributors: David Crisp1, Yasjka Meijer2, Rosemary Munro3, Kevin Bowman1, Abhishek Chatterjee4,5, David Baker6, Frederic Chevallier7, Ray Nassar8, Paul I. Palmer9, Anna Agusti-Panareda10, Jay Al-Saadi11, Yotam Ariel12. Sourish Basu13,14, Peter Bergamaschi15, Hartmut Boesch16, Philippe Bousquet7, Heinrich Bovensmann17, François-Marie Bréon7, Dominik Brunner18, Michael Buchwitz17, Francois Buisson19, John P. Burrows17, Andre Butz20, Philippe Ciais7, Cathy Clerbaux21, Paul Counet3, Cyril Crevoisier22, Sean Crowell23, Philip L. DeCola24, Carol Deniel25, Mark Dowell26, Richard Eckman11, David Edwards13, Gerhard Ehret27, Annmarie Eldering1, Richard Engelen10, Brendan Fisher1, Stephane Germain28, Janne Hakkarainen29, Ernest Hilsenrath30, Kenneth Holmlund3, Sander Houweling31,32, Haili Hu31, Daniel Jacob33, Greet Janssens-Maenhout15, Dylan Jones34, Denis Jouglet19, Fumie Kataoka35, Matthäus Kiel36, Susan S. Kulawik37, Akihiko Kuze38, Richard L. Lachance12, Ruediger Lang3, Jochen Landgraf 31, Junjie Liu1, Yi Liu39,40, Shamil Maksyutov41, Tsuneo Matsunaga41, Jason McKeever28, Berrien Moore23, Masakatsu Nakajima38, Vijay Natraj1, Robert R. Nelson42, Yosuke Niwa41, Tomohiro Oda4,5, Christopher W. O’Dell6, Leslie Ott5, Prabir Patra43, Steven Pawson5, Vivienne Payne1, Bernard Pinty26, Saroja M. Polavarapu8, Christian Retscher44,
    [Show full text]
  • What Was the Source of the Atmospheric CO2 Increase During the Holocene?
    Biogeosciences, 16, 2543–2555, 2019 https://doi.org/10.5194/bg-16-2543-2019 © Author(s) 2019. This work is distributed under the Creative Commons Attribution 4.0 License. What was the source of the atmospheric CO2 increase during the Holocene? Victor Brovkin1, Stephan Lorenz1, Thomas Raddatz1, Tatiana Ilyina1, Irene Stemmler1, Matthew Toohey2, and Martin Claussen1,3 1Max-Planck Institute for Meteorology, Hamburg, Germany 2GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel, Germany 3Meteorological Institute, University of Hamburg, Hamburg, Germany Correspondence: Victor Brovkin ([email protected]) Received: 22 February 2019 – Discussion started: 4 March 2019 Revised: 7 June 2019 – Accepted: 12 June 2019 – Published: 2 July 2019 Abstract. The atmospheric CO2 concentration increased by face alkalinity decrease, for example due to unaccounted for about 20 ppm from 6000 BCE to the pre-industrial period carbonate accumulation processes on shelves, is required for (1850 CE). Several hypotheses have been proposed to ex- consistency with ice-core CO2 data. Consequently, our sim- plain mechanisms of this CO2 growth based on either ocean ulations support the hypothesis that the ocean was a source or land carbon sources. Here, we apply the Earth system of CO2 until the late Holocene when anthropogenic CO2 model MPI-ESM-LR for two transient simulations of climate sources started to affect atmospheric CO2. and carbon cycle dynamics during this period. In the first simulation, atmospheric CO2 is prescribed following ice- core CO2 data. In response to the growing atmospheric CO2 concentration, land carbon storage increases until 2000 BCE, 1 Introduction stagnates afterwards, and decreases from 1 CE, while the ocean continuously takes CO2 out of the atmosphere after The recent interglacial period, the Holocene, began in 4000 BCE.
    [Show full text]
  • Carbon Cycle the Carbon Cycle Is the Biogeochemical Cycle by Which Carbon Is Exchanged Among the Biosphere, Pedosphere, Geospher
    Carbon Cycle The carbon cycle is the biogeochemical cycle by which carbon is exchanged among the biosphere, pedosphere, geosphere, hydrosphere, and atmosphere of the Earth. Carbon is the main component of biological compounds as well as a major component of many minerals such as limestone. Along with the nitrogen cycle and the water cycle, the carbon cycle comprises a sequence of events that are key to make Earth capable of sustaining life. It describes the movement of carbon as it is recycled and reused throughout the biosphere, as well as long-term processes of carbon sequestration to and release from carbon sinks. Carbon sinks in the land and the ocean each currently take up about one-quarter of anthropogenic carbon emissions each year. Following are the major steps involved in the process of the carbon cycle: 1. Carbon present in the atmosphere is absorbed by plants for photosynthesis. 2. These plants are then consumed by animals and carbon gets bioaccumulated into their bodies. 3. These animals and plants eventually die, and upon decomposing, carbon is released back into the atmosphere. 4. Some of the carbon that is not released back into the atmosphere eventually become fossil fuels. 5. These fossil fuels are then used for man-made activities, which pumps more carbon back into the atmosphere. Atmospheric carbon cycle The carbon exchanges between reservoirs occur as the result of various chemical, physical, geological, and biological processes. The ocean contains the largest active pool of carbon near the surface of the Earth.[13] The natural flows of carbon between the atmosphere, ocean, terrestrial ecosystems, and sediments are fairly balanced so that carbon levels would be roughly stable without human influence.[3][14] Carbon in the Earth's atmosphere exists in two main forms: carbon dioxide and methane.
    [Show full text]
  • In Situ Oceans and Atmosphere (LSCOP)
    A Large-Scale CO2 Observing Plan: In Situ Oceans and Atmosphere (LSCOP) A Report of the In Situ Large-Scale CO2 Observations Working Group Front Cover: Global map of the world. The land colors show the composite NASA SeaWiFS Vegetation Index. The ocean colors show the climatological mean air-sea CO2 fluxes for the virtual year 1995 (after Takahashi et al., 2002). The surrounding pictures show the various sampling platforms and equipment that are used as part of the air and seawater CO2 observing network. The SeaWiFS data were provided courtesy of the NASA SeaWiFS Project Office and ORBIMAGE Corporation. The CO2 flux data were provided by Taro Takahashi of Lamont-Doherty Earth Observatory of Columbia University. The photos were provided by Christopher Sabine, Richard Feely, Britton Stephens, and Pieter Tans. ALarge-ScaleCO2 Observing Plan: In Situ Oceans and Atmosphere (LSCOP) In Situ Large-Scale CO2 Observations Working Group: Bender, M., S. Doney, R.A. Feely, I. Fung, N. Gruber, D.E. Harrison, R. Keeling, J.K. Moore, J. Sarmiento, E. Sarachik, B. Stephens, T. Takahashi, P. Tans, and R. Wanninkhof A contribution to the implementation of the U.S. Carbon Cycle Science Plan April 2002 NOTICE Mention of a commercial company or product does not constitute an endorsement by NOAA/OAR. Use of information from this publication concerning proprietary products or the tests of such products for publicity or advertising purposes is not authorized. For sale by the National Technical Information Service, 5285 Port Royal Road Springfield, VA 22161 ii Contents iii Contents Executive Summary 3 1. ObservationObjectives...................... 4 2.
    [Show full text]
  • A Review of Carbon Dynamics and Sequestration in Wetlands
    Journal of Wetlands Ecology, (2009) vol. 2, pp 42-46 Open access at www.nepjol.info/index.php/JOWE Wetland Friends of Nepal www.wetlandsnepal.org Review Paper A Review of Carbon Dynamics and Sequestration in Wetlands Shalu Adhikari 1, Roshan M. Bajracharaya 1 and Bishal K. Sitaula 2 Address: 1Department of Environmental Science and Engineering, Kathmandu University, Dhulikhel, Nepal 2 Department of International Environment and Development Studies, University of Life Sciences, Norway *Corresponding author: [email protected] Accepted: 22 April, 2009 Abstract Wetlands are among the most important natural resources on earth. They provide a potential sink for atmospheric carbon but if not managed properly, they become a source of green house gases. However, only limited studies have been conducted to assess the roles and potentials of wetlands in carbon sequestration. Wetlands occupy approximately 5% of the total land area in Nepal, some of these being of international importance. However, there are major knowledge gaps in accurately quantifying carbon stored in them, as well as their carbon sequestration potential. Therefore, further research is needed to better understand the processes of carbon sequestration in wetland vegetation and soils. Key words: wetland, sink, carbon sequestration Introduction Wetlands are found in all climatic zones ranging from tropics to the tundra (except Antarctica which has no wetlands). Occupying about 5% of the earth’s land area, wetlands are dynamic and natural ecosystems characterized by water logged or standing water conditions during at least part of the year. In most wetlands, water levels fluctuate seasonally instead of being stable, a property that accounts for making wetlands highly productive environments.
    [Show full text]
  • 69 Radiocarbon – a Unique Tracer of Global Carbon
    RADIOCARBON, Vol 42, Nr 1, 2000, p 69–80 © 2000 by the Arizona Board of Regents on behalf of the University of Arizona RADIOCARBON – A UNIQUE TRACER OF GLOBAL CARBON CYCLE DYNAMICS Ingeborg Levin • Vago Hesshaimer Institut für Umweltphysik, University of Heidelberg, Im Neuenheimer Feld 229, D-69120 Heidelberg, Germany. Email: [email protected]. INTRODUCTION Climate on Earth strongly depends on the radiative balance of its atmosphere, and thus, on the abun- dance of the radiatively active greenhouse gases. Largely due to human activities since the Industrial Revolution, the atmospheric burden of many greenhouse gases has increased dramatically. Direct measurements during the last decades and analysis of ancient air trapped in ice from polar regions allow the quantification of the change in these trace gas concentrations in the atmosphere. From a presumably “undisturbed” preindustrial situation several hundred years ago until today, the CO2 mixing ratio increased by almost 30% (Figure 1a) (Neftel et al. 1985; Conway et al. 1994; Etheridge et al. 1996). In the last decades this increase has been nearly exponential, leading to a global mean CO2 mixing ratio of almost 370 ppm at the turn of the millennium (Keeling and Whorf 1999). The atmospheric abundance of CO2, the main greenhouse gas containing carbon, is strongly con- trolled by exchange with the organic and inorganic carbon reservoirs. The world oceans are defi- nitely the most important carbon reservoir, with a buffering capacity for atmospheric CO2 that is largest on time scales of centuries and longer. In contrast, the buffering capacity of the terrestrial biosphere is largest on shorter time scales from decades to centuries.
    [Show full text]
  • Enhanced Carbon Sequestration for Climate Change Mitigation and Co-Benefits in Agriculture
    INTERVIEW Interview with Britton Stephens Carbon Management (2014) 5(2), 109–113 “ The amount of knowledge about our earth and the climate system that has been gained from sustained measurements of atmospheric CO2 and other gases is immeasurable, yet these programmes are required to justify themselves as hypothesis-driven experiments every 3 years to funding agencies with oscillating budgets and priorities. ” Britton Stephens Britton Stephens is a Scientist III in the Earth Observing Laboratory of the National Center for Atmospheric Research in Boulder (CO, USA). He received a bachelor’s degree in earth and planetary sciences from Harvard in 1993 and a PhD in oceanography from the Scripps Institution of Oceanography in 1999. Before joining NCAR in 2002, he completed a post-doctoral fellowship with the National Oceanic and Atmospheric Administration’s Carbon Cycle and Greenhouse Gases group. His research has focused on developing and deploying new instruments for tower, ship, and aircraft-based observations of atmospheric O2 and CO2, and on synthesizing data sets and models to elucidate global carbon cycle processes. He maintains a network of CO2 instruments in the US Rocky Mountains and an O2 instrument on a ship in the Southern Ocean. His research contributions include a synthesis of airborne data that led to a major revision of model-based estimates of the global distribution of terrestrial CO2 fluxes. Britton Stephens speaks to Ruth Williamson, Commissioning Editor for Carbon Management, about promising state-of-the-art instruments for measuring atmospheric carbon cycle species, the challenges of conducting research on land, oceans and in the air, and important future directions for carbon cycle research.
    [Show full text]
  • Baseline Assessment of Carbon Stocks Report
    Assessment Forest Plan Revision Draft Baseline Assessment of Carbon Stocks Report Prepared by: Dennis Sandbak Silviculturist for: Custer Gallatin National Forest November 29, 2016 Contents Introduction .................................................................................................................................................. 1 Process and Methods .................................................................................................................................... 2 Scale .......................................................................................................................................................... 2 Existing Information Sources .................................................................................................................... 2 Current Forest Plan Direction ....................................................................................................................... 3 Existing Condition ......................................................................................................................................... 3 Key Benefits to People .................................................................................................................................. 8 Trends and Drivers ........................................................................................................................................ 8 Trends ......................................................................................................................................................
    [Show full text]
  • Water and Carbon Cycling
    Water and carbon cycling New A Level Subject Content Overview Author: Martin Evans, Professor of Geomorphology, School of Environment, Education and Development, University of Manchester. Professor Evans was chair of the ALCAB Geography panel. 1. Water and Carbon Cycles Cycling of carbon and water are central to supporting life on earth and an understanding of these cycles underpins some of the most difficult international challenges of our times. Both these cycles are included in the core content elements of the specifications for A Level geography to be first taught from 20161. Whether we consider climate change, water security or flood risk hazard an understanding of physical process is central to analysis of the geographical consequences of environmental change. Both cycles are typically understood within the framework of a systems approach which is a central concept to much physical geographical enquiry. The concept of a global cycle integrates across scales. Systems theory allows us to conceptualise the main stores and pathways at a global scale. The systems framework also allows for more detailed (process detail) and local knowledge to be nested within the wider conceptual framework. Local studies on aspects of hydrology or carbon cycling can be understood as part of a broader attempt to understand in detail the nature of water and carbon cycling. Global environmental challenges frequently excite student interest in physical geography but it can be difficult for students to see how they can conduct relevant investigations of fieldwork given the large scale and complexity of the issues. By embedding their knowledge within systems framework students can understand how measurements and understanding derived from their own fieldwork and local studies contribute to the wider project of elucidating the cycling of water and carbon at the global scale.
    [Show full text]