Natural Carbon Pathways Flashcards
How does photosynthesis regulate the composition of the atmosphere?
By balancing oxygen and carbon dioxide.
How is soil health important in carbon pathways?
Some carbon is returned to soils by dead plant material being decomposed. In this way, carbon is stored in organic matter that is mixed in the soil.
This is important for soil health, as organic matter helps retain soil moisture and nutrients, which in turn improves the productivity of an ecosystem by providing water and dissolved nutrients for plants to absorb through their roots to grow.
When did fossil fuel consumption begin?
Since the Industrial Revolution, coal, oil and gas have been taken from the ground and used by the industries. Compared to the natural carbon cycle this happened very fast. Atmospheric CO2 levels are now higher than at any time in the past 800000 years, so temperatures are increasing more.
What are the implications for the climate (because of fossil fuel consumption)?
-Temperate and tropical areas may have stronger storms because of more heat energy and moisture in the atmosphere.
-Fewer extreme cold events but more extreme hot events due to average temperature increase.
-Biggest increase in average temperatures will be in the Arctic as more heat is transferred from the tropics.
-Precipitation patterns will change, higher near the poles and decreasing in the subtropics as warmer air can hold more moisture.
What are the implications for the ecosystems?
-10% of land species face extinction due to an inability to adapt/move when climate conditions change. Highest risk in polar areas.
-80% of coral reefs could be ‘bleached’ by warmer seawater and suffer chemical weathering as oceans become more acidic.
-Disease and pests will increase as they thrive in warmer conditions and are not killed by cold winters.
-Biodiversity will reduce as habitats shift towards poles or into deeper ocean waters, changing food webs.
What are the implications for the hydrological cycle?
-Shift of subtropical high pressure areas towards poles will increase drought conditions in Mediterranean climate zones.
-Permafrost will melt, adding more water into the Artic rivers and streams.
-River discharges will decrease in areas with lower precipitation and lower effective precipitation.
-Cryosphere store will decrease as glaciers retreat/ice sheets have surface ablation; this will also increase river discharges at first, then decrease them.
