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Good to the Last Drip: How Trees Help to Reduce Pollution

This article is from Issue Urban Forest - Vol. 6 No. 1.

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In the past, scientists had estimated how much rainfall is intercepted by trees growing in rural areas. The scientists in this study wanted to know how much rainfall is intercepted by the trees that grow in an urban county in California. 

Welcome to the Urban Forests edition

Note to Educators

Urban Forest Lesson Plan

Reflection Section Answer Guide

Education Standards Correlations


Meet the scientists that contributed to this article:

"Science Topics" covered in this article:
  • Life Science
  • People and Science
  • Technology and Science

"Environmental Topics" covered in this article:
  • Atmosphere (Educators)
  • Importance of Forest to People (Students)
  • The Value of Forests and Grasslands (Educators)
  • Water (Educators)

Regions covered in this article:
  • Alaska
  • Forest Products Lab
  • Intermountain
  • International Institute of Tropical Forestry
  • Northern
  • Pacific Northwest
  • Pacific Southwest
  • Rocky Mountain
  • Southern
  • Southwestern

"Thinking About Science Themes" covered in this article:
One of the best things about science is that scientists will never learn everything. Even when scientists are pretty sure of something that they've learned, new information may cause them to revise their thinking. Scientists, therefore, will never run out of new things to study! In this research, the scientists wanted to know how much rainfall is intercepted by trees growing in urban areas. In the past, other scientists had estimated how much rainfall was intercepted by trees growing in rural areas. Since urban areas and rural areas are different, the scientists in this study felt that urban trees should be studied separately. When this study was finished, do you think that the scientists knew everything about rainfall interception by urban trees? Why or why not?
Specific "Thinking About Science" Themes:
  • Characteristics of Scientists
  • Scientific Topics

"Thinking About Environmental Themes" covered in this article:
Natural systems are organized so that the environment will remain balanced. For example, when there is a lot of rainfall and few trees in an area, the rainfall can cause soil erosion and might cause flooding. When trees are growing in an area, the leaves, branches, trunk, and roots help to reduce soil erosion and flooding. Rain falls on the tree, where it is stopped or slowed down. Roots absorb water for the tree's use. The trees are a form of control that helps to protect the soil from erosion and the area from flooding. In natural areas that have a lot of rain, you will find a lot of trees. You can find this kind of regulation in all natural systems, including your own body! Can you think of one way that your body keeps your own amount of water balanced?
Specific "Thinking About the Environment" Themes:
  • Regulation

NSE Standards covered in this article:
  • Abilities necessary to do scientific inquiry (A)
  • Diversity and adaptations of organisms (C)
  • Nature of science (G)
  • Personal health (F)
  • Properties and changes of properties in matter (B)
  • Regulation and behavior (C)
  • Risks and benefits (F)
  • Science and technology in society (F)
  • Science as a human endeavor (G)
  • Structure and function in living systems (C)
  • Structure of the earth system (D)
  • Understandings about scientific inquiry (A)

Science Benchmarks covered in this article:
  • Habits of Mind: Communication Skils
  • Habits of Mind: Critical-Response Skills
  • Human Society: Social Trade-Offs
  • The Living Environment: Interdependence of Life
  • The Mathematical World: Symbolic Relationships
  • The Nature of Mathematics: Mathematics, Science, and Technology
  • The Nature of Science: Scientific Inquiry
  • The Nature of Science: The Scientific Enterprise
  • The Physical Setting: Processes that Shape the Earth
  • The Physical Setting: The Earth