This tutorial will cover the topic of agricultural impacts. We will discuss several negative environmental impacts that result from agricultural practices, in addition to the impacts of agroecosystems and their practice of monoculture. Lastly, we will cover practices that are employed to mitigate these problems.
Our discussion breaks down as follows:
- Agriculture Impacts on the Environment
- Addressing Negative Agriculture Impacts
1. Agriculture Impacts on the Environment
At the making of this tutorial, nearly half of our planet is used for agriculture. There are many negative environmental impacts that result from agricultural practices. These include:
Water pollution: Mainstream agriculture employs the use of synthetic fertilizers and pesticides. These chemicals are not inert, and can easily run off of fields and into water systems, causing water pollution problems.
Loss of biodiversity: Most agricultural land was once a natural ecosystem. The changing of previously undeveloped land destroys habitat and threatens wildlife. As a result, there is a loss of biodiversity while there is an increase in agricultural land.
Soil erosion: Mainstream agricultural practices commonly cause soil erosion, which over time reduces nutrients and topsoil available for growing crops.
Deforestation: It is common for forest land to be razed for agricultural use, and this practice is reducing wildlife habitat and total forest area globally.
As more land gets transformed for agricultural use, we are changing natural ecosystems into agroecosystems. Agroecosystems tend to have a low genetic diversity, low species diversity, and low habitat diversity. All three are problematic for a stable, healthy ecosystem.
Agroecosystems tend to have low diversity because they are designed to control a small number of species in a given area for human use, whereas natural ecosystems allow for a larger diversity of species to have progression and succession over time.
In order to have the highest amount of efficiency and control, most agriculture tends to practice monoculture, which is the cultivation of a single crop, like the corn crop shown below.
Monoculture can cause a number of issues:
Reduction of soil nutrients: Because only one type of crop is being grown in a single plot of land, there is an increased need for fertilizer, which leads to depletion of the same type of nutrients that the crop needs to grow.
Pest adaptation to a single crop species: Because there is no crop diversity, local pests can adapt to decimate whole fields, which then increases the need for pesticides.
Degradation in water quality: Because there is an increased need for both fertilizer and pesticides, chemical runoff increases, polluting water systems and damaging aquatic ecosystems, all of which eventually leads to harming human health.
4. Addressing Negative Agriculture Impacts
Luckily, there are ways to mitigate and transform these negative environmental impacts. Organizations and government institutions can provide information on methods, and they can subsidize technologies to mitigate impacts.
Three primary methods of transforming negative impacts are:
- Organic agriculture
- Sustainable agriculture
- Regenerative agriculture
Organic agriculture seeks to avoid synthetic compounds, instead using more natural sources and methodologies, such as crop rotation, composting, and natural pesticides and fertilizers. In this photo, an organic cattle farm in Ohio is pasture-raising their cows, instead of giving them processed feed.
Sustainable agriculture's methods seek to prevent negative impacts through practices — like composting and no-till farming — that take part in the natural cycles around them, instead of degrading resources.
For example, this farm below composts their waste and re-uses it to grow food instead of using chemical fertilizers.
Regenerative agriculture's main goal is to improve the surrounding ecosystems' resources. This is primarily done by creating and replenishing soils and their nutrients. In the photo below, you can see topsoil being slowly created with leaves and other organic materials.
Today we learned about the various impacts of agriculture, such as the runoff of chemical fertilizers into waterways, polluting our drinking water, the loss of biodiversity in land developed for agriculture, soil erosion, and deforestation. We learned about agroecosystems and the negative impacts of practices like monoculture, or the cultivation of a single crop. Finally, we explored ways to mitigate or transform these negative impacts through practices like organic, sustainable, and regenerative agriculture.