Off-site

Propagation and preservation of plant, animal, and micro-organism species outside their natural habitat.


Oil seed crops

Primarily soybeans, peanuts, cottonseed, and flaxseed used for the production of oils for cooking, protein meals, and nonfood uses. Less common oil crops include sunflower, safflower, castor beans, and sesame.


On-site

Preservation of species in their natural environment.


Open-pollinated

Plants that are pollinated by physical or biological agents (e g, wind, insects) and without human intervention or control)


Optimum sustainable population

the number of animals which will result in the maximum productivity of the population or the species, keeping in mind the carrying capacity of the habitat and the health of the ecosystem.


Organic

In this guide, matter from living, or once-living, things.

 


Organic Agriculture

The practice of growing crops without use of chemical fertilizers and pesticides.


Organic food

Plants and animals that are grown or reared without the use of synthetic fertilisers, pesticides or hormones.

 


Organism

Any living thing, from bacteria and fungi through to insects, plants, animals and humans.

 


Orthodox seedsSeeds that are able to withstand the reductions in moisture and temperature necessary for long-term storage and remain viable.

Over exploitation

Over exploitation occurs when harvesting of specimens of flora and fauna species from the wild is out of balance with reproduction patterns and, as a consequence, species may become extinct.


Over fishing

Harvesting so many fish of a species (especially immature fish) that there is not enough breeding stock left to replenish the species, such that it is not profitable to harvest them, leading to commercial extinction .


Overgrazing

Destruction of vegetation when too many grazing animals feed too long and exceed the carrying capacity of a rangeland area.


Ozone layer

The thin protective layer of gas 10 to 50km above the Earth that acts as a filter for ultraviolet (UV) radiation from the sun. High UV levels can lead to skin cancer and cataracts and affect the growth of plants