8.6 - pollution management strategies, acid rain and photochemical smog

management strategies

• public transit expansion

• promotion of electric transport

• natural screens

• green spaces

• compulsory catalytic converters

• low emission zones

• pedestrianisation

public transit expansion

expanding and improving public transport

• to reduce nr of private vehicles

• lower primary pollutants

natural screens

rows of trees/ shrubs alongside roads

• trap pollutants and reduce their spread

green walls

vegetated walls that

• absorb pollutants

• reduce heat

• improve air quality

urban green spaces functions

• filter pollutants

• provide shade

• reduce urban heat island effect

catalytic converters

devices fitted to vehicle exhaust

• reduce harmful emissions

low emission zones

areas with restricted access for vehicles not meeting specific emission standards

pedestranisation

pedestrian only zones in city centres

• promote healthier lifestyles

• lower emission

acid rain

any form of precipitation that has been acidified by chemical reactions in the atmosphere

• primary from SO2 and NOx

formula for sulphuric acid

2SO2 + O2 → 2SO3

SO3 + H2O → H2SO4

formula for nitric acid

2NO + O2 → 2NO2

@NO2 + H2O → HNO3 + HNO2

transboundary pollution

pollutants that travel long distances, crossing country boundaries

leaching due to acid rain

acid rain accelerates leaching

aluminium toxification of the soil

• acid rain increases solubility of toxic metals

• released from soil particles into soil solution

• INDIRECT NUTRIENT EFFECT

  • Al: toxic for plant roots 

aluminium solubilisation

• solubilisation can lead to toxic concentration of Al in water bodies

• Al = highly toxic to aquatic organisms

• disruption of ion balance in fish

• impaired gill function

acid rain impact on trees

DIRECT EFFECT

• damaged leaves and needles by dissolving way coating

  • increased disease

• leaf discolouration

  • reduced photosynthetic capacity

impact of acid rain on infrastructure

• accelerates corrosion of marble and limestone

• increased maintenance costs

• loss of cultural heritage

effects of acid rain on human health

• respiratory issues from NOx and SO2

• tissue damage and lung inflammation

managing acid rain

• altering human activity

• controlling release of pollutants

• clean up and restoration of damaged systems

photochemical smog

air pollution that forms when sunlight trigger reaction between pollutants

peroxyacyl nitrates PANs

powerful respiratory and eye irritants

• higher = damage to vegetation

• mutagenic → cause skin cancer

factors causing photochemical smog

• abundant insolation

• reduced wind speed

• temperature inversion

• mountains

• combined effects

temperature inversion

layer of warm air traps cooler air

• prevents pollutants from rising and dispersing

direct impacts of photochemical smog

biological impacts

• damage to plant cuticles and membranes

• eye irritation

physical impacts

• damage to fabrics

• damage to rubber materials