Defining Biodiversity

Biodiversity is the pairing of two words, ‘biology’ and ‘diversity’.  Both are important words, and together they describe ‘life on earth’.  

There are several commonly accepted definitions of biodiversity, and each of them recognise the importance of—and need for—diversity of species within an environment, and for wide genetic diversity within each of those species.  Unfortunately all definitions fail to articulate just how important the mass or volume of species is within an environment.  A more exact definition, and the definition we encourage you to use in managing holistically, is:
  • The diversity of species within an environment
  • The genetic diversity of each of those species
  • The mass or volume of each of those species
The combination of these three factors leads to environmental stability, although one should never equate the word ‘stability’ with ‘nothing happening’!  The greater the biodiversity, the greater the number of interactions that are happening at any time within dynamic communities.  It’s the essence of the ecosystem process known as community dynamics!

Diversity of species
Not only must there be a wide range of species, but the age structure of all species present must be diverse.  This is required to avoid the situation where all the "right species" are present in the environment, but there are few or no young, indicating that some species are dying out, leading to biodiversity loss.

Genetic diversity
Loss of genetic diversity risks environmental instability.  A disease or weakness can spread rampantly, just as phytophthora infestans devasted the Irish potato crop in September 1845, and Southern Corn Leaf Blight in the USA in 1970.  In 1970 it is thought that at least 80 percent of the hybrid corn in America contained T-cytoplasm, and these plants were genetically susceptible to a fungus that mutated to become known as "race T" of Helminthosporium maydis.  A major food crisis was only narrowly averted in the USA that year.

Mass of life
It is important to avoid a situation where all the right species are present, but each in so few numbers that you could hardly call the situation healthy.  Think about a zoo, where there are thousands of species, but only a few members of each species.  Such environments are very unstable, and animal deaths would begin within hours should the paid zoo keepers not be doing their job.  


It is difficult to sustain oneself when biodiversity declines

Agriculture, and therefore civilisation, cannot be sustained without biological diversity (biodiversity).
 
At some point, losses in biodiversity seem to always result in the failure of a civilisation's agriculture.  Because agriculture is a key industry, without it no businesses, artisans, or governments endure.  Sustainability is an issue of biological stability.

Biodiversity represents the only true wealth civilisations have ever had, no matter how they measured it.  As we lose biodiversity we lose "capital."  That's why, managing holistically takes as its foundation the four processes at work in the ecosystem, and why every decision tested is done so in light of how it will affect any one of them.  

An advance in Community Dynamics, an increase in Energy Flow, or an improvement in the Water Cycle or Mineral Cycle, is a replenishment of capital.

In the absence of biological stability there is no opportunity for civilisation to take root.  The term is not used in a judgmental way and makes no commentary about the intelligence of individuals or races of people.  It reflects that civilisation can only develop when there is sufficient environmental stability for people to live permanently in towns and cities, and to be occupied in activities other than food production.  Without such stability humans operate as nomadic hunters and gatherers.  

Some scientists say that this isn't true any more, that technology is on the brink of overcoming our dependence on biodiversity.  But even if we did manage to grow all our food with genetically engineered seed in hydroponic conditions (water laced with the appropriate chemical nutrients) we'd still be in trouble.  In the absence of disturbance, over-rested soils in the vast regions of brittle tending environments of the world would continue to silt up our rivers and destroy our irrigation works, and the life in our lakes and seas.  The air we breathe would still be dependent on the mass of life that ensures its chemical composition remains conducive to human life.


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