<< Chapter < Page Chapter >> Page >
In this module, the following topics are covered: 1) biodiversity, 2) trends in biodiversity loss with reference to species and ecosystems, 3) ways human activity affects biodiversity, and 4) biodiversity loss effects on people

Learning objectives

After reading this module, students should be able to

  • define biodiversity
  • articulate current trends in biodiversity loss with reference to species and ecosystems
  • explain some of the ways human activity affects biodiversity
  • explain how biodiversity loss concerns people

What is biodiversity?

You're probably familiar with the word, biodiversity    , whether or not you can give an exact definition of it. It's common on the signs at zoos, parks, and nature centers, and it's often used without explanation or definition. Most people understand biodiversity in general terms as the number and mix of plant and animal species that occurs in a given place. Scientists are more precise and include more in their definition. The International Union for the Conservation of Nature (IUCN) , which coordinates efforts to catalogue and preserve biodiversity worldwide, defines biodiversity as "the variability among living organisms from all sources including terrestrial, marine and other aquatic ecosystems, and the ecological complexes of which they are part; this includes diversity within species, between species, and of ecosystems." Rather than just species, biodiversity therefore includes variation from the level of genes and genomes to that of ecosystems to biomes.

Even within a single ecosystem, the numbers of species can be impressive. For example, there is a large region of dry forest and savanna in Brazil known as the Cerrado (see Figure Cerrado Forest ). This ecosystem alone hosts over 10,000 species of plants, almost 200 species of mammals, over 600 species of birds, and about 800 species of fish.

Cerrado Forest
Cerrado Forest . Photograph of the Cerrado Forest. Source: C2rik via Wikimedia Commons .

Generally, biodiversity is greatest in tropical areas–especially "rainforests"—but there are terrestrial biodiversity "hotspots" on all the major continents. (View an interactive map of hotspots .)

One way scientists gauge trends in biodiversity is by monitoring the fate of individual species of animals and plants. For more than 40 years, the IUCN has compiled information in the "Red List of Threatened Species," which "provides a snapshot of what is happening to species around the world." Updates to the Red List are released every four years. Here is how the authors of the most recent one, released in 2008, characterize the news it holds: "The overwhelming message" from the 2008 Red List, they write, "is that the world is losing species and that the rate of loss appears to be accelerating in many taxonomic groups" ( Vie, Hilton-Taylor,&Stuart, 2008, p. 38 ).

Summary of Threatened Species . Table lists the numbers and proportions of species assessed as threatened on the 2008 IUCN Red List by major taxonomic group. Source: IUCN Red List, Wildlife in a Changing World 2008 , p. 17. Please see IUCN Terms of Use for copyright restrictions.

Questions & Answers

What is the law of demand
Yaw Reply
price increase demand decrease...price decrease demand increase
Mujahid
ıf the price increase the demand decrease and if the demand increase the price decrease
MUBARAK
all other things being equal, an increase in demand causes a decrease in supply and vice versa
SETHUAH
yah
Johnson
how is the economy of usa now
Johnson
What is demand
jude Reply
Demand is the quantity of goods and services a consumer is willing and able to purchase at various prices over a given period of time.
Yaw
yea
SETHUAH
Okay congratulations I'll join you guys later .
Aj
yes
MUBARAK
calculate elasticity of income exercises
HABANABAKIZE Reply
If potatoes cost Jane $1 per kilogram and she has $5 that could possibly spend on potatoes or other items. If she feels that the first kilogram of potatoes is worth $1.50, the second kilogram is worth$1.14, the third is worth $1.05 and subsequent kilograms are worth $0.30, how many kilograms of potatoes will she purchase? What if she only had $2 to spend?
Susan Reply
cause of poverty in urban
DAVY Reply
QI: (A) Asume the following cost data are for a purely competitive producer: At a product price Of $56. will this firm produce in the short run? Why Why not? If it is preferable to produce, what will be the profit-maximizing Or loss-minimizing Output? Explain. What economic profit or loss will the
Falak Reply
what is money
DAVY Reply
money is any asset that is generally acceptable for the exchange of goods and for the settlement of debts
Mnoko
what is economic
Stephen Reply
economics is the study of ways in which people use resources to satisfy their wants
Falak
what is Price mechanism
Dhany Reply
what is Economics
ERNESTINA
The study of resource allocation,distribution and consumption.
Emelyn
introduction to economics
Uday Reply
welfare definition of economics
Uday
examine the wealth and welfare definitions of economics
Uday
read book by ml jhingan
Anand
What do we mean by Asian tigers
Aeesha Reply
Dm me I will tell u
Shailendra
Hi
Aeesha
hi
Pixel
What is Average revenue
KEMZO
How are u doing
KEMZO
it is so fantastic
metasebia
uday
Uday
it is a group of 4 countries named Singapore, South Korea, Taiwan and Hong Kong because their economies are growing very faster
Anand
fyn
EDWARD
Please, average revenue is an amount of money you gained after deducted your total expenditure from your total income.
EDWARD
what's a demand
Edward Reply
it is the quantity of commodities that consumers are willing and able to purchase at particular prices and at a given time
Munanag
quantity of commodities dgat consumers are willing to pat at particular price
Omed
demand depends upon 2 things 1wish to buy 2 have purchasing power of that deserving commodity except any from both can't be said demand.
Bashir
Demand is a various quantity of a commodities that a consumer is willing and able to buy at a particular price within a given period of time. All other things been equal.
Vedzi
State the law of demand
Vedzi
The desire to get something is called demand.
Mahabuba
what is the use of something should pay for its opportunity foregone to indicate?
Random Reply
Why in monopoly does the firm maximize profits when its marginal revenue equals marginal cost
astrid Reply
different between economic n history
Falma Reply
Got questions? Join the online conversation and get instant answers!
Jobilize.com Reply
Practice Key Terms 5

Get Jobilize Job Search Mobile App in your pocket Now!

Get it on Google Play




Source:  OpenStax, Sustainability: a comprehensive foundation. OpenStax CNX. Nov 11, 2013 Download for free at http://legacy.cnx.org/content/col11325/1.43
Google Play and the Google Play logo are trademarks of Google Inc.

Notification Switch

Would you like to follow the 'Sustainability: a comprehensive foundation' conversation and receive update notifications?

Ask