Understanding the need for biodiversity

This page has reported on many aspects of sustainability in recent months. This week I look at one more – biodiversity. This is another loosely defined term that refers to the amount of life around us.

Biodiversity is really a name which describes every living organism within an ecosystem or habitat. It embraces the number and diversity of species within that ecosystem. It can be measured globally or in smaller local settings such as a farm, or even a pond.

It keeps nature going

In nature, every single species has a role to play. Some have gone while new ones are still being discovered. Generally, one feeds off another and they all have a part to play in keeping the circle of life going. This circle operates within an ecosystem and generally a range of plant species take in carbon from the atmosphere and utilise nutrients from their surroundings to generate plant dry matter.

Some, even many, of these natural organisms cause problems for animals and plants

This is then consumed by a host of animal species and their excrement returns the nutrients to the soil where they are again freed for re-use by a host of microorganisms.

Some, even many, of these natural organisms cause problems for animals and plants. Others cause problems for humans and these are generally seen in a different light and frequently targeted for extinction. Take COVID-19 as an example – it is part of the planet’s biodiversity and yet the whole world is trying to eradicate it.

Healthy

An agricultural ecosystem (the mix of all living things in it and how they interact with one another) is very different to a rain forest ecosystem, or a desert. Rivers, lakes, and oceans also have their own ecosystems, but they are all most influenced by the activities of humans.

Many different enterprises contribute to farm output to provide income across much of the year

Systems that depend on one or two species can be regarded as delicate. The greater the number of species that an ecosystem can support, the higher is the rate of survival of the organisms therein. And this includes the human species. Put simply: Plants support insects, insects support birds, birds have predators, dead life is recycled by a range of organisms, and so on.

An ecosystem is broadly similar to a very traditional system of farming. Many different enterprises contribute to farm output to provide income across much of the year. Farm produce feeds the family while other farm produce and waste feeds the animals. This system of farming was more diverse and biodiverse, but it was forced to change through the need to survive, specialise and intensify. These are all forces outside of the control of an individual farmer, and societal change has been the major catalyst. This same society is now blaming farming for doing what it had to do to try to survive.

Whatever the causes of the loss, it is important for farming to realise that biodiversity is a good thing. It is not the enemy of efficiency or productivity.

What farmer does not enjoy the sight of butterflies, birds singing and nesting, plants flowering and a range of wildlife?

But it is also important for society to realise that the biodiversity levels associated with unmanaged nature are not possible within a food production system that is asked to feed an expanding population. The challenge for us all is to do more to make things better. Biodiversity affects the places we live and work.

What farmer does not enjoy the sight of butterflies, birds singing and nesting, plants flowering and a range of wildlife?

But they also know that too many rabbits eat a lot of grass or crop, crows and pigeons can become big pests, and foxes and other carnivores can kill newborn lambs. Balancing the need for biodiversity and survival is trickier when these things happen.

How is biodiversity measured

Biodiversity is more than what we see and is loosely described as:

The area involved can be large or small. We can look at the ecological biodiversity of the Burren or a mountain range or the bogs of the midlands.

It can also be a local forest, a park or even a pond on your land. These are all ecological habitats or ecosystems in which biodiversity can be measured.

Humans are a single species but genetically individuals are visibly diverse

Genetic diversity can be the genetic makeup of a single species of bovine, sheep or crop. It is also the range of genetic variation within a single species, such as the number of animal breeds or insect or bird or plant species. Humans are a single species but genetically individuals are visibly diverse.

The soil beneath our feet is potentially a home for massive biodiversity. We recognise the earthworms and some of the insect larvae but there are also billions of microorganisms that live and work there.

There is a growing realisation among farmers of the importance of biodiversity. It is also being realised at EU and national policy levels. But we must begin by recognising that we already have a level of biodiversity in our landscapes compared with many other countries.

Biodiversity begins with plants so anything that adds more plant species helps

We have forests, woods, hedges, mountains, and a lot of extensively managed grassland. But in many instances, these belong to some farms while others are much more limited.

Biodiversity begins with plants so anything that adds more plant species helps. These can be within a grassland sward or the introduction of other crops or land uses to an area. Most insects and bees depend on flowering plants, but these are often not present in grazed grassland.

So, is there a small area on your farm where you can let nature take hold and go back to extensive management to enable flowering and seed production?

Biodiversity in plant species then supports the existence of additional insects, bees, birds etc

This might be a poor corner in a field, an un-grazed strip along by a river or drain, the planting of different tree species in similar areas, allowing hedges to bulk up, the planting of wild flowers in a patch, leaving a bit more unused area beside hedges, planting new hedges, having additional annual crops in a region, etc. Any one of these will help but doing more than one helps even more. Biodiversity in plant species then supports the existence of additional insects, bees, birds etc, which also act as additional stores of carbon. We might also add that actions should not just be confined to fields. What people everywhere do in their gardens, even in towns and cities, is also important.