Environmental Safety Biodiversity

What is biodiversity?

Biodiversity means variety of life forms. Regions home to many different species are high in biodiversity. Variety within populations of a single species can also be considered a contribution to biodiversity. Ecosystems with high biodiversity are characterised by complex interactions between different species, which can help the ecosystem remain intact and healthy in the face of disturbance and environmental change. For this reason, looking at biodiversity is a good parameter for assessing the overall health of an ecosystem.

Agro-Biodiversity: Wild flowers in a rapeseed field.

Wild plants on the farm Producing crops, by its very nature, means getting rid of wild plants on the farm. There are many management strategies used by farmers to reduce the growth of weedy wild plants. If other plants are permitted to grow alongside crops, the crops will have to compete for valuable resources such as light, water, and nutrients. This would have huge negative effects on crop productivity. A certain presence of wild plants on the field, however, can actually be helpful. Wild plants make a more attractive environment for certain animals that are known to deter pests. Well thought-out agricultural practices leave a place for wild plants and still provide crops with good growing conditions.

Agriculture using genetically modified crops must respect this balance. Environmental safety research is conducted to see if traits of genetically modified plants could have a negative impact on biodiversity. Theoretically, there a few ways in which biodiversity could be compromised:

• Out-crossing: If GM plants pass their new traits on to wild relatives, those relatives could be changed in a way that could make them play a different ecological role, potentially enabling them to out-compete other species.

• Agricultural practices: Herbicide tolerant GM plants are examined to see how the associated weed management strategies affect the number of wild plants found in fields. Many such studies have been carried out in Great Britain and in Germany. On a case-by-case basis, researchers must determine if specific GM cropping systems lessen or improve biodiversity with relation to conventional crops and see if any differences are of significance.

• New traits conferred by genetic engineering could offer advantages that could lead to the widespread use of only a few crop varieties – in other words, a loss of cultivar biodiversity. Reducing the diversity of cultivars found in agriculture could lead to problems such as higher susceptibility to widespread outbreaks of plant diseases and pests.

In general, seed companies rarely release only a single cultivar with a new genetically engineered trait; rather, they will introduce the same trait by breeding to many different cultivars. Therefore, using genetically engineered crops doesn’t necessarily mean reducing the diversity of cultivars. It is, nonetheless, a good idea to keep a close eye on this in the long term.

See also on GMO-Compass:

• Out-crossing and Gene Flow