16 - The Changing Environment Flashcards
(29 cards)
Natural events that cause environmental change
- Seasonal changes
- Natural disasters
- Natural climate changes due to orbit changes, solar variations
- Changes in species relationships
Man made events that cause environmental change
- Land use/farming
- Deforestation
- Urbanisation
- Increasing population
- Pollution
- Climate change
What are microbes critical for
- Colonising and promoting all animal life on planet
- Photosynthesis (5 groups contribute to carbon fixation)
- Recycle nutrients
- Enrich soils for plant growth
Volcanic activity
- Dramatic effects on localised environment
- Volcanic gas and ash into atmosphere, react with atmospheric gases
- Lava flows damaging surrounding area
- Tsunamis
Volcanic gas and ash reacting with atmospheric gases
- Conversion of sulfur dioxide to sulphuric acid
- Ozone destruction
- Increase in CO2
Natural cycle of climate change
- The earth goes through naturally induced cooling and warming events
- Occur of very long periods of time
Microbes and climate change
- Control biogeochemical cycling of all elements essential for life
- Generate and consume gases that effect climate
Drought
- Prolonged drought leads to desertification and loss of microbial diversity and functionality
- 20% of the earths soil has been degraded by drought
- Has significant impact on
ability to grow crops
Flooding
- Soils saturated in water have reduced microbial diversity
- Increase in methanotrophs, decrease in aerobic activity
- Leads to chemical contamination of soils and environment
Effect of pollution on microbial communities
- Atmospheric pollution contains heavy metals that convert to more toxic compounds
- Farm land river run off increases nitrates in seas and river ecosystems
- Accumulation of inorganic waste in soils and in the ocean
- Fecal pollution from humans and farming effects diversity
and abundance of microbes in aquatic systems
Primary pollutants
- Carbon monoxide
- Sulphur dioxide
- NItrogen dioxide
Secondary pollutants
- Nitric acid
- Sulphuric acid
- Hydrogen peroxide
Many infectious diseases are impacted by changing environment
- Land clearing can bring new diseases into proximity to new populations
- Air pollution can increase impact of viral respiratory infections
- Chemical pollution can make humans more susceptible to
infections - Climate change has increased range and indeicence of vector borne infections
Airborne pollution and respiratory infections
- Airborne pollution has been shown to effect both the SARS and SARS-cov-2 disease symptoms
- Exposure to sulphur dioxide increases risk of influenza infections
How do inhaled pollutants reduce host immunity
- Enhanced viral activation and entry
- Impaired TLR activation
- Impaired intracellular pathway activation
- Impaired antiviral immune signalling
- IMpaired immune cell function
Control of malaria
- Draining of swamps
- Long been used to reduce malaria transmission in endemic regions
Why look at microbes to measure change
- Microbes respond to small changes to their environment
- Can be used as a sensitive measure of environmental change
- Exist in every environment in great diversity
- Evolve fast - faster reflection of change
- Easily studied in the lab
- No ethics
Metataxanomics
- Using an amplicon to classify microbes
- Lacks information
Metagenomics (WGS sequencing)
- Sequences genomic material of complete biome
- Huge data
Metatranscriptomics
Sequencing of microbial transcriptome
rtPCR sequencing
Required for RNA viral diversity
Bioremediation
- Process that uses microbes to repair environmental damage by using harmful contaminants as source of energy
- Help prevent further degradation
Bioaugementation
Addition of bacterial cultures to contaminated mediums
Biofilters
Use of microbial columns to treat air emissions of volatile compounds
