ESS 6.4: Acid Deposition

what is the source of acid deposition?

the combustion of fossil fuels produces primary pollutants (oxides of nitrogen & sulfur dioxide) which may be converted into secondary pollutants of dry deposition (sulfates & nitrates) or wet deposition (sulfuric & nitric acids)

what is wet deposition?

acidic rain, snow or other precipitation (sulfuric and nitric acids)

what is dry deposition?

acidic gas or dry particles, not mixed with water (sulfates and nitrates)

what are the effects of acid deposition on soil?

increased acidity leads to accelerated leaching of calcium out of the soil, affects the mineral content

acid run runoff is absorbed by the soil

some organisms can’t tolerate the change in PH

reduces the population of soil microorganisms

what are the effects of acid deposition on water?

affects the chemical and pH balance in groundwater

damages organisms

eutrophication

makes aquatic environments toxic due to excess aluminium created by acid rain

acid rain runoff from trees and forest floors infiltrates forest water

what are the effects of acid deposition on organisms?

as acid rain falls on trees, it damages leaves, stunts their growth and damages their bark

makes trees/plants vulnerable to disease, extreme weather and insects

trees uptake toxic aluminiums ions from soil

reduced photosynthesis

causes respiratory issues if inhaled

why is it that the impact of acid deposition occurs far from the source of pollution?

the impacts may be limited to areas downwind of major industrial regions due to the way the air is blowing

Pollution management strategies for acid deposition: altering human activity

reducing use or finding alternatives to fossil fuels

use more energy-efficient appliances

use public-transport

incentives/disincentives (produced by government)

educating citizens; campaigns → raising awareness

Pollution management strategies for acid deposition: regulating the release of pollutants

install ‘scrubbers’ to remove SO2 (acidified emissions)

catalytic converters on automobiles

legislation and regulation of emissions

Pollution management strategies for acid deposition: restoring ecosystems

adding lime to acidified lakes and streams → to balance acidity and repair damage to the pH

adding lime to forest plantations

replanting/restocking/re-greening lost or depleted communities

captive breeding of endangered species