To grow and photosynthesise, trees need water, which gets transported from the roots to the leaves. As water evaporates from the leaves, a negative pressure is created which pulls water through the trunk upwards through tiny hollow tubes called xylem. In the leaves, light splits water molecules to make the oxygen you breathe, and to react with carbon dioxide and make sugars. By pumping water, trees also cool the air and stabilise the soil.
International day of forests
The United Nations General Assembly proclaimed the 21th of March as the International Day of Forests (IDF). This day celebrates and raises awareness of the importance of all types of forests. The theme of this year is “Forests & Energy”, while last year this day was focused on “Forests & Water”. With regard to last year’s theme, the United Nations gathered some more “Did you know’s” about forests and water:
- Forested watersheds and wetlands supply 75 percent of the world’s accessible freshwater
- About one-third of the world’s largest cities obtain a significant proportion of their drinking water directly from forested protected areas
- Nearly 80 percent of the world’s population is exposed to high levels of threat to water security
- Improved water resource management can show considerable economic gains
- Forests act as natural water filters
- Climate change is altering forests role in water flows and the availability of water resources
- Forests have a crucial role in building and strengthening resilience
Enough reasons to plant a tree today!