Ecosystem Quiz: What Do You Know About Restoring Earth’s Bionetworks?

Natália G.R. de Mello holds doctorate and masters degress in environmental science and works as a contributor for 8 Billion Trees.Written by Natalia Mello

Quizzes Tests | March 15, 2024

An 8 Billion Trees illustration of ecosystem restoration, with a woman and people planting trees.

Use this ecosystems quiz to test your knowledge about Earth’s bionetworks, and gain insight on restoration with these fun questions!

Question 1) What is the UN Restoration Decade?

  •  Aiming to counter different environmental emergencies and rehabilitate degraded landscapes, the UN launched the decade on ecosystem restoration in 2021.1

Question 3) True or False? Trees are the plant species most suited to restore any given landscape under any circumstance.

  • Although trees are an excellent way to sequester carbon dioxide, they may not always be the first nor only choice to restore certain environments. Some environments may not naturally support trees, so other plant species should be considered. Bamboo, for instance, can regenerate bare land quickly.3 

Question 4) Forest restoration projects are considered meaningful if the plant species can ___________.Men working to compost brown matter to help fertilize tree saplings for reforestation efforts in Brazil, with an 8 Billion Trees watermark.

  •  Forests grow and mature slowly, and making sure restored forests will survive for decades is key to maximizing the social and ecological benefits they provide.4

Question 5) Which of the following strategies is not considered a correct approach to restoration?

  • Aiming at planting as many trees as possible – especially without carefully selecting diverse species – has been causing some poorly planned restoration efforts to fail.5 

Question 6) What is a biodiversity hotspot?

A view into the lush green canopy of the Amazon rainforest in Yasuni National Park, Ecuador, with an 8 Billion Trees watermark.

  • Biodiversity hotspots, like tropical rainforests, have high and unique biodiversity and have only 30% or less of their natural vegetation cover.6 

Question 7) True or False? Degraded farmlands cannot be restored.

  • Degraded farmlands can, and must, be restored. Luckily, many techniques can facilitate that.2 

Question 8) Some big restoration projects fail because they did not make smart planting choices. Out of the 50 million seedlings planted in Northern Nigeria, how many have withered and died within two months?

  • Those seedlings were planted in extremely dry areas, causing the local population to compete with trees for water.7 

Question 9) What aspects should be considered for a successful ecosystem restoration program? 

  • It is fundamental that restoration programs respect the local culture and knowledge, empower local communities, care for trees instead of just planting them, and focus on quality rather than quantity.2 

Question 10) How many trees should be grown so that the world meets the target set by the UN Decade on Ecosystem Restoration? Remember… Although tree growing is not the only strategy to ensure restoration, these plant species play a big role in this global effort! 

  •  The UN Decade on Ecosystem Restoration has set the ambitious target of planting 3 trillion trees across the world by the year 2030.2 


1UN Decade on Restoration. (n.d.). Retrieved July 29, 2021, from  

2World Resources Institute. (2021, May 17). Pressing Questions About Ecosystem Restoration, Answered. Retrieved July 29, 2021, from 

3World Resources Institute. (2014, June 24). 3 Myths and Facts about Forest and Landscape Restoration. Retrieved July 29, 2021, from

4Reid, L. (2019, March 18). Restoring tropical forests isn’t meaningful if those forests only stand for 10 or 20 years. Retrieved July 29, 2021, from 

5World Resources Institute. (2014, May 28). Restoration: It’s About More than Just the Trees. Retrieved July 29, 2021, from

6What Are Biodiversity Hotspots? (n.d.). Retrieved July 29, 2021, from 

7Dead baby trees by the millions as reforestation fails. (2008, April 7). Retrieved July 29, 2021, from