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Most importantly, the ecological importance of natural areas is worth preserving. Wilderness areas help maintain ecosystem diversity. They protect watersheds, help to improve air quality and provide a natural undisturbed laboratory for scientific study.

Genetic diversity

Whereas ecosystem diversity is a measure of variability among populations of species, genetic diversity refers to variability among individuals within a single species population. A gene represents the fundamental physical unit of heredity, and each individual in a species a different mix of genes. This genetic diversity -- or variation within species allows populations to adapt to changes in environmental conditions. Millions of years of adaptive change may be encoded in the genes of a species population, and it is those genes that provide the basis for future adaptations.

Loss of genetic diversity makes a species less able to reproduce successfully and less adaptable to a changing environment. Small populations of species are especially susceptible to loss of genetic diversity. When a species loses too many individuals, it becomes genetically uniform. Some of the causes for the loss in genetic diversity include: inbreeding among closely related individuals, and genetic drift in which the genes of a few individuals, eventually dominate in a population.

Genetic diversity is important to agriculture. Much of the world's agriculture is based on introduced or hybrid crop strains, as opposed to native or wild strains . The main purpose of using hybrid stains is to increase productivity. Unfortunately, this approved results in only a few hybrid crop strains being used for commercial agriculture. These hybrid crops lack the genetic diversity of the many wild strains, and the resistance of hybrids to pests and disease is generally much lower. Therefore, it is necessary to protect and conserve the wild strains as a genetic library, from which one can draw the genetic information necessary for producing improved and more resistant hybrid strains. A similar situation exists in livestock breeding, except that the loss of genetic diversity in livestock has even more severe consequences. Many livestock breeds are near extinction because of the policy of favoring a few specialized breeds. It is clear that human activity is primarily responsible for the genetic erosion of plant and animal populations.

Food resources

The three major sources of food for humans are: croplands, rangelands and fisheries. Croplands provide the bulk of human food. Even though there are thousands of edible plants in the world, only four staple crops (wheat, rice, corn and potatoes) account for most of the caloric intake of humans. Some animals raised for meat, milk and eggs (e.g. cattle, pigs, poultry) are also fed grain from croplands. Rangelands provide another source of meat and milk from grazing animals (e.g. cattle, sheep, goats). Fisheries provide fish, which are a major source of animal protein in the world, especially in Asia and coastal areas. For mainly economic reasons, the diets of most people in the world consist of staple grains. As people become more affluent, they tend to consume more meat, eggs, milk and cheese.

Questions & Answers

How we are making nano material?
LITNING Reply
what is a peer
LITNING Reply
What is meant by 'nano scale'?
LITNING Reply
What is STMs full form?
LITNING
scanning tunneling microscope
Sahil
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
Bob
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
research.net
kanaga
sciencedirect big data base
Ernesto
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
Bharti
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
Daniel
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
Maciej
characteristics of micro business
Abigail
for teaching engĺish at school how nano technology help us
Anassong
How can I make nanorobot?
Lily
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
NANO
how can I make nanorobot?
Lily
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
s.
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
Tarell
what is the actual application of fullerenes nowadays?
Damian
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
Tarell
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
Virgil
is Bucky paper clear?
CYNTHIA
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
NANO
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Ap environmental science. OpenStax CNX. Sep 25, 2009 Download for free at http://cnx.org/content/col10548/1.2
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