Benefits of trees Flashcards
How do trees improve soil?
- erosion control
- nutrient pumping
- facilitation
What is NPS (nonpoint source pollution) pollution caused by?
- Rainfall or snowmelt moving over and through the ground.
- As precipitation and irrigation water moves, it picks up turf chemicals, oils and other pollutants that eventually end up in streams and lakes
How can trees/shrubs and grasses stop NPS pollution?
when they are planted in bio-swales, wetlands and riparian forests, they are buffers that can filter out contaminants as they slow and capture storm runoff. They filter out the urban impurities and reduce the amount of runoff and amount of sediments and pollutants
What causes NPS pollution and polluted runoff?
- fertilizers, herbicides and insecticides from agricultural fields and urban lawns
- nutrients and bacteria from concentrated livestock operations
- sediment from croplands, urban construction sites and eroding stream banks
- oils, antifreeze and salts from city streets and parking lots
By how much can urban forests reduce annual storm-water runoff?
- by 2-7
- a mature tree can store 50 to 100 gallons of water during large storms
How can trees improve stream-bank stability?
- goundcover holds topsoil in place/ tree roots penetrate deep and spread out, anchoring large blocks of soil
- densely planted trees and shrubs can traffic off slopes that are prone to wind and water erosion
- a very fibrous root system can keep the topsoil in place
How do trees clean the air?
by absorbing carbon dioxide, sulfur dioxide, nitrous oxides (all greehouse gases) and other pollutants, and also shade cars and parking lots, reducing ozone forming emissions from vehicles
Define windbreaks
trees on both sides of an area to block wind particles and windspeed
Define SALT
- Sloping Agricultural Land Technology
- on sloping lands, keep the main forest or wooded land on top and then keep a good nitrogen fixer next, then fir trees, then shrubs, then other crops like tobacco, etc. and then crops like low-lying rice.
- you don’t need to add fertilizer because the trees provide all the necessary stuff for soil content, wind break, etc.
Define phytoremediation
the process in which trees, along with shrubs, and grasses (poplar, willow, paulowina tree) absorb and break down contaminants (industrial sites solvents, heavy metal and petroleum residues leach into the groundwater and wash into rivers and streams)
Why are there concerns about heavy metals running into lakes and streams (phytoremediation)?
- the edible portions eventually end up in your stomach, so need to be careful of these toxic metals, etc. getting into crops
- some of the food crops that you consume here and in Europe has lots of cadmium (but the portion taken up by our stomach is negligible compared to the uptake from our lungs
What poses major environmental, agricultural and human health problems worldwide?
contaminated soils and water
What species thrives on contaminated soils and cleans them up by removing the excess metals?
Alpine pennycress (Thlaspicaerulesnens)
Why should green spaces be designed with a variety of plant species?
- to guard against major losses from insects and disease
- to help diversify the urban landscape
- these areas could also be havens for native and rare plants and animals
Studies have found that property values increased by what with the presence of trees and vegetation on a property?
37%
