4.1 engineered ecosystems and modern agriculture

Unlike most species, humans spend little time in natural ecosystems. Sometimes, the features of an ecosystem are recognizable, while other times, the majority of the biotic features have been eliminated. Using the graphic organizer provided, compare and contrast Engineered Ecosystems with Natural Ecosystems. Refer to both abiotic and biotic characteristics.

Tools: powered by hand or horse and have been used for thousands of years; have done less to alter natural landscape

Concentrated energy sources: recent use of fossil fuels have given us the ability to literally move mountains

Can humans change the basic relationships that exist between the environment and ourselves? Explain.

No. 

To live sustainably, we must not disrupt abiotic and biotic conditions we need to survive. 

Actions that disrupt water and nutrient cycles, threaten biodiversity, or alter climate patterns, jeopardize our ability to survive.

Recreational activities such as hiking, boating, or swimming are natural resources

Provide food, shelter, buildings such as schools and doctors offices are engineered recourses Eating is one of our fundamental biological activities. Unlike other animals, humans obtain very little food from natural ecosystems. Instead, where is our food produced?

Most of our food is produced on large agricultural farms. Most fruits/vegetable crops are grown in large fields; meat is provided by a few kinds of domesticated animals that are raised on farms.

Even though most of our food sources are grown in Canada, the majority does not come from species native to Canada. All major foods we produce in Canada are exotic species that were introduced from other parts of the world. Over time, humans have domesticated these non-native plants and animals. These food species are productive, nutritious, and relatively easy to produce in large quantities. Complete the table below on “Selected Native and Non-Native Crops and Livestock species Grown and Raised in Canada.”

Agroecosystems, or agricultural ecosystems, differ from natural ecosystems in many ways. Complete the graphic organizer to compare and contrast the farmland with natural ecosystems. Consider both abiotic and biotic features.

How do farmers alter the abiotic and biotic growing conditions to manage agroecosystems?Farmers use 

• non-native species, 

• typically grown in a monoculture,

•  manage pests

• change the soil composition and water cycle to alter growing conditions (ploughing, weeding, fertilizing, irrigation, pesticide use)

  Monoculture: the cultivation of a single crop in an area

  
  

  This results in an ecosystem that is not stable. Stable ecosystems have high biodiversity and species richness. They are made up of several producers and consumers.