Lec 16 - Microbes and a changing environment Flashcards
What are some results of a changed environment?
- Improve/reduce survival
- Adapt, move or die
- Replacement of one organism with another
- Changes in relationships between organisms
List natural events leading to environmental change
- Seasonal changes
- Natural disasters
- Natural climate changes = orbital changes, solar variations, internal variability, ocean currents
- Changes in species relationships/ecosystems
List man-made events leading to environmental change
- Land use changes and farming
- Deforestation and flora destruction
- Urbanisation
- Increasing population
- Migration to new environments
- Environmental contamination = indirect from pollution and waste, direct from mining and resource sector
- Animal/plant extinction
Climate change
What are the roles of bacteria that make them critical to the environment?
- Colonise and promote all life
- 5 photosynthetic bacteria groups contribute to C fixation
- Recycle nutrients and alter basic compounds
- Enrich soils for plant growth
How does volcanic activity change the environment?
- Gas and ash react with atmospheric gases
- Lava flows damage land
- Cause tsunamis
What are the 4 main processes of microbes that generate or consume compounds?
- Consume inorganic C as CO2 and reduce it
- Consume and trap methane via methanotrophy
- Consume organics to produce CO2, CH4 and N2O
- Fix nitrogen which increases with increases CO2
How does drought affect microbial diversity?
- Causes desertification and loss of microbial diversity/functionality
- Fungal diversity increases as microbial diversity decreases
How does flooding affect microbial diversity?
Causes saturation and loss of microbial diversity by increased methanotrophs and decreased aerobes
How does atmospheric pollution affect microbes?
- Heavy metals are converted to toxic compounds
- Acidificaton and altered microbial diversity
How does run off affect microbes?
Increases nitrate which increases growth and decreases O2 = impacts food chain
How do organic and inorganic pollutants affect microbes?
Organic = leach into everything
Inorganic = accumulates in soils/ocean
List examples of primary and secondary pollutants
Primary = CO, NO, SO2, NH3, NO2
Secondary = SO3, HNO3, H2O2, H2SO4, NH4+
How do the following changed environments impact infectious disease?
- Land clearing
- Draining swamps
- Air pollution
- Chemical pollution
- Human waste
- Climate change
- Agricultural land use
- Land clearing = new diseases
- Draining swamps = reduce vectors
- Air pollution = increases respiratory infections
- Chemical pollution = increased susceptibility
- Human waste = reservoir and source
- Climate change = increased range of vectors
- Agricultural land use = increased pollution and damage
How are arsenic and leishmaniasis linked?
Borehole construction into arsenic contaminated rocks in India in Himalayas created indirect resistance to leishmaniasis antimony drug
How is SARS-CoV 1 and 2 and airborne pollution linked?
Increased pollution increased mortality in both SARS-CoV infections from increased susceptibility to inflammation by increased ACE-2 receptors, comorbidity and impaired immunity
