Ecoscience: Population, Resources, Environment

By Paul R. Ehrlich; Anne H. Ehrlich et al. | Go to book overview

CHAPTER 2
The Physical World

All the rivers run into the sea; yet the sea is not full.

--Ecclesiastes

The biosphere is that part of Earth where life exists. In vertical dimension it extends from the deepest trenches in the ocean floor, more than 11,000 meters (36,000 feet)1 below sea level, to at least 10,000 meters (m) above sea level, where spores (reproductive cells) of bacteria and fungi can be found floating free in the atmosphere. By far most living things -- most of which depend directly or indirectly on the capture of solar energy by photosynthesis in plants and certain bacteria -- exist in the narrower region extending from the limit of penetration of sunlight in the clearest oceans, less than 200 meters from the surface, to the highest value of the permanent snow line in tropical and subtropical mountain ranges -- about 6000 meters, or 20,000 feet. ( Everest, the highest mountain, rises almost 8900 meters above sea level.) By any definition, the biosphere is as a mere film in thickness compared to the size of the ball of rock on which it sits -- about like the skin of an apple, in fact. The radius of Earth is about 6370 kilometers (km), or 4000 miles (mi).

Of course, conditions within the thin envelope of the biosphere are influenced by physical processes taking place far outside it: by the energy emitted by the sun, 150

____________________
1
Throughout this book physical dimensions are given in metric units, sometimes accompanied by the English equivalent to ease the transition for readers not completely accustomed to the metric system. For more precise conversion factors, see the tables inside the covers of the book.

-11-

Notes for this page

Add a new note
If you are trying to select text to create highlights or citations, remember that you must now click or tap on the first word, and then click or tap on the last word.
One moment ...
Default project is now your active project.
Project items

Items saved from this book

This book has been saved
Highlights (0)
Some of your highlights are legacy items.

Highlights saved before July 30, 2012 will not be displayed on their respective source pages.

You can easily re-create the highlights by opening the book page or article, selecting the text, and clicking “Highlight.”

Citations (0)
Some of your citations are legacy items.

Any citation created before July 30, 2012 will labeled as a “Cited page.” New citations will be saved as cited passages, pages or articles.

We also added the ability to view new citations from your projects or the book or article where you created them.

Notes (0)
Bookmarks (0)

You have no saved items from this book

Project items include:
  • Saved book/article
  • Highlights
  • Quotes/citations
  • Notes
  • Bookmarks
Notes
Cite this page

Cited page

Style
Citations are available only to our active members.
Buy instant access to cite pages or passages in MLA, APA and Chicago citation styles.

(Einhorn, 1992, p. 25)

(Einhorn 25)

1. Lois J. Einhorn, Abraham Lincoln, the Orator: Penetrating the Lincoln Legend (Westport, CT: Greenwood Press, 1992), 25, http://www.questia.com/read/27419298.

Cited page

Bookmark this page
Ecoscience: Population, Resources, Environment
Table of contents

Table of contents

Settings

Settings

Typeface
Text size Smaller Larger Reset View mode
Search within

Search within this book

Look up

Look up a word

  • Dictionary
  • Thesaurus
Please submit a word or phrase above.
Print this page

Print this page

Why can't I print more than one page at a time?

Help
Full screen
/ 1052

matching results for page

    Questia reader help

    How to highlight and cite specific passages

    1. Click or tap the first word you want to select.
    2. Click or tap the last word you want to select, and you’ll see everything in between get selected.
    3. You’ll then get a menu of options like creating a highlight or a citation from that passage of text.

    OK, got it!

    Cited passage

    Style
    Citations are available only to our active members.
    Buy instant access to cite pages or passages in MLA, APA and Chicago citation styles.

    "Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn, 1992, p. 25).

    "Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn 25)

    "Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences."1

    1. Lois J. Einhorn, Abraham Lincoln, the Orator: Penetrating the Lincoln Legend (Westport, CT: Greenwood Press, 1992), 25, http://www.questia.com/read/27419298.

    Cited passage

    Thanks for trying Questia!

    Please continue trying out our research tools, but please note, full functionality is available only to our active members.

    Your work will be lost once you leave this Web page.

    Buy instant access to save your work.

    Already a member? Log in now.

    Author Advanced search

    Oops!

    An unknown error has occurred. Please click the button below to reload the page. If the problem persists, please try again in a little while.