Brownfield Blooms

ENVIRONMENT

Industrial wastelands sound like grim places but many of them are refuges for fascinating plants. (Guardian)

Exotic flowers thrive in nutrient-poor soils, but what are nutrients? Use our resources to find out.

Teachers, scroll down for a quick list of key resources in our Teachers’ Toolkit.


Discussion Ideas

 

  • One of the common characteristics of brownfield sites is their nutrient-poor soil. What is a nutrient? Use our easy encyclopedic entry for some help.
    • Nutrients are chemical substances found in every living thing on Earth. They are necessary to the lives of people, plants, animals, and all other organisms.
    • Plants usually absorb nutrients from soil and water. The most important nutrients for plants are often grouped together by the acronym CHNOPS (shnahps). The letters stand for the elements’ chemical abbreviations:
      • C (carbon)
      • H (hydrogen)
      • N (nitrogen)
      • O (oxygen)
      • P (phosphorus)
      • S (sulfur)
      • Other important nutrients are calcium (Ca) and magnesium (Mg).

 

  • Read through the super-short Guardian article. What are some of its examples of industrial activities contributing to nutrient-poor soils?
    • Runoff and waste from a former sewage-processing plant contributed to one area’s calcareous soil. Calcareous simply means “chalky,” and chalky soils do not contain many nutrients.
    • Runoff and waste from a sodium carbonate factory contributed to another area’s alkaline soil. (Sodium carbonate is a major component of glass manufacturing.) Alkaline soil is a type of clay (soil) that contains salts (alkalis). Alkaline soil is notoriously nutrient-poor and for that reason is considered one of the most difficult soils to develop for agriculture.
    • Finally, tons of fly ash from coal-fired power plants were dumped in pits along the Thames estuary. Fly ash contributed to an extremely alkaline freshwater marsh ecosystem.

 

  • With such poor soil, how do orchids obtain nutrients they need to survive?
    • Orchids are strange plants that don’t have a traditional root system.
      • Many orchids are epiphytes, meaning they grow on another plant (usually a tree or shrub), not in soil. In fact, immersion in soil may smother delicate orchid roots. These orchids obtain water and nutrients from air, precipitation, and the debris that collects around them.
      • Some orchids are tubers, meaning they have enlarged structures used for collecting and storing nutrients.

 

  • What other plants have adapted to nutrient-poor soils?
    • A lot!
      • Many succulents, such as cacti, are able to collect and store scarce water and nutrients for long periods of time.
      • Rain forests are some of the planet’s most important carbon sinks, but most nutrients (including carbon) are part of the vegetation itself, not the soil. Rain forest soil is notoriously poor.
      • Some of our favorite plants that have adapted to nutrient-poor soils are carnivorous plants, such as Venus flytraps and sundews. These plants obtain nutrients through the decaying bodies of their insect prey.

 

 

TEACHERS’ TOOLKIT

Guardian: From the wasteland a rich carpet of orchids

Nat Geo: What is a nutrient?

Nat Geo: Do-It-Yourself Bioblitz

One response to “Brownfield Blooms

  1. Pingback: What’s at Stake in Proposed Cuts to the EPA? | Nat Geo Education Blog·

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