Engineered ecosystems and modern agriculture

Leon likes taking long walks in the forest with Uncle Seamus. Leon’s always surprised how many different plants and animals there are. And Uncle Seamus knows so much about all of them! Uncle Seamus always gladly explains to Leon how these animals and plants interact — how this natural ecosystem works. But most natural ecosystems have been changed by humans.

They are no longer the same — they’ve been engineered! What does Uncle Seamus mean? Look around and it’s clear that most places people live differ significantly from wild areas of nature. Humans have altered our natural environment — by building cities, farms, and roads — to make it suit our needs. An ecosystem changed by humans is usually a mix of living and non-living, natural and man-made elements.

We call this an artificial or engineered ecosystem. Farms are one example of an engineered ecosystem — they are an agricultural ecosystem. To create a farm, the natural environment is altered — farmers remove natural vegetation and transform land into pastures or fields. Then, farmers usually choose only certain crops and often plant them in nice, neat rows to make harvesting easier. Many of these crops originally come from a completely different part of the world.

They are not from the area; they are non-native species. Take corn, for example. Until the 1500s, corn only grew in Central America. Today it’s grown all over the world! To help crops grow in size and quantity, farmers use different substances to add nutrients, kill weeds and pests, and protect plants from diseases.

They also supply water, using irrigation systems when there isn’t enough rain. Farmers who raise animals affect natural ecosystems too. Farmers often choose just one type of domesticated animal to raise, such as cows, or chickens. Specialising like this, makes it easier to raise animals in large numbers and make money from them. It is also easier than trying to control wild, undomesticated, native species.

Big modern farms often use strict methods and technology, so that a farm resembles a well-designed factory. Technological solutions allow farmers to have almost total control over temperature, humidity, the amount of light and nutrients. Crops can be grown in greenhouses or indoors, using artificial lighting. Some crops for example are grown without soil at all, with their roots immersed in nutrient-rich liquid. Technology helps with livestock farming too, for example feeding or milking cows.

Farmers engineer agricultural ecosystems to better control the environment and to deliver more produce. But all this engineering can have negative consequences. In engineered ecosystems, there are usually fewer different species than in natural ecosystems. This makes the ecosystem itself less resilient. Also engineered ecosystems need humans to maintain them at all times.

Farmers need to constantly add nutrients to the soil, or fight pests and diseases that are more likely to spread. There are other concerns about industrial farming too. It can cause pollution, it doesn't usually consider the well-being of animals, and it often destroys the natural environment. Some modern farms, however, are specifically designed to mimic natural ecosystems. Farmers increase biodiversity by growing many different types of crops and raising different types of animals.

The more biodiversity a farm has, the more resilient it becomes. It needs less human intervention and the ecosystem on the farm can self-regulate. Whether it’s a huge industrial farm, or a small one trying to simulate nature, all farms are ecosystems. They belong to the great ecosystem of the earth. But when we modify nature, it's our responsibility to make sure we don't harm the planet.