How Organic Agriculture Increases Biodiversity
Organic farms have a higher diversity of plants, insects and animals, according to multiple scientific studies. Wildlife can find shelter more easily in the clusters of wild plants usually growing on organically managed land. Abundance of native plants comes with benefits for local animals, that are perfectly adapted to live alongside them. A research paper from 2015 claims that the positive effect of organic agriculture on local biodiversity could be observed in 80 % of investigated cases [3].
A study from Oxford University revealed that organic farms generally show an increase in both species abundance and richness. The variety of species includes native plants, birds, insects and for soil fertility essential soil organisms. Even species in charge of pollination were found at 50% higher abundance than at conventional farms [1].
However, as researchers highlight, any kind of agricultural activity represents degradation of original habitats, and the type of farm management or the number of areas where wild plants grow is not sufficient enough to preserve native species in their original diversity. All farmers should bear the responsibility for the way of using the land and adopt some biodiversity conservation measures.
Positive changes in biodiversity can be seen even after first attempts of switching to more environmentally friendly practices such as performing agro-forestry, or the principles of permaculture. And it is a worthy investment in the long run, since biodiversity itself performs multiple ecosystem services to agricultural units as well. Perhaps the most important one to mention is improved resistance to diseases and pests.
Why organic agriculture?
The reason why there is a difference in biodiversity between organic farming and conventional farming, is that organic farming does not use chemical pesticides and fertilizers to achieve better yields. The use of these chemicals triggers many negative processes in the natural environment.
For example, the purpose of herbicides is to eradicate weeds from crops, but it also negatively affects insects and birds depending on these plants which were present there for many decades before. Equally, the application of pesticides does not only remove pests but also their predators, impacting the whole food chain.
Other biodiversity-friendly practices used in organic agriculture include:
- soil nutrient enhancing crop rotation
- cover cropping as prevention of erosion
- fertilization with compost or manure
- nutrient recycling
- mixed crop and livestock production in one farm [1]
Interesting fact
Practices used in organic agriculture are especially inviting for beneficial species of birds. Many of these birds are sensitive to pollution and loss of habitat, and therefore, are a good indicator of environmental degradation. Number of birds on a farm helps us to determine the overall quality of a habitat in the anthropogenic landscape. An additional advantage of bird presence on farms are the ecosystem services they offer. They keep pest numbers under control, facilitate pollination, prevent outbreaks of diseases, and even lower the risk of soil erosion.
For example, waterfowls wintering in California enhance straw decomposition on rice fields, while searching for food. Their activity decreases the need for tillage, which helps to preserve the amount of nutrients in the soil, but also saves farmers’ money [2].
What can farmers do to enhance local biodiversity?
Biodiversity is different at each farm. Farmers can boost it by avoiding the use of pesticides, replacing chemical weeding with mechanical; fertilizing soil with manure rather than with synthetic fertilizers; and using crop rotation to achieve a balanced level of nutrients in the soil. By creating diverse habitats on unutilized parts of a property species can find their little havens for breeding and feeding.
Perfect elements of landscape are water retention basins, fallow areas, or hedgerows. The most important rule to follow is to keep these parts different from the most prevailing form of land use at farm, for example, keeping stripes of native vegetation between monoculture crops.
Biodiversity comes with innumerable benefits for the quality of life on our planet, and landscape with a high variety of flora and fauna is more stable in the long run than a life-deprived one. The greatest impact on biodiversity on farms lies in the hands of a farmer, but even you can help to protect it by supporting local organic farms. By purchasing local or organic farmers’ produce, your money will help them to keep doing their valuable jobs at an age when they have to compete against intensive, profit-focused super-farms.
[2] https://tilth.org/resources/lessons-learned-biodiversity-birds-organic-farms/
[3] http://www.intechopen.com/books/biodiversity-in-ecosystems-linking-structure-and-function/impact-of-organic-farming-on-biodiversity