Stomatal Atmospheric Conditions | The density of stomata on leaf surfaces/fossils indicates CO₂ in atmosphere
[increased CO₂ = increased stomata density]
[Limited as few plants change stomatal density and different species have different stomatal density] |
Ice Cores' Atmospheric Conditions | Ice forms one layer per year; air is trapped in the ice, the trapped air can be measured and analysed |
Ice Cores' Temporal Conditions | Higher abundance of Oxygen-18 [isotope] and Hydrogen-2; fewer heavy isotopes during colder periods |
Habitat Destruction | Creating dams, straightening rivers, clearing land, land+soil degradation [clearing land rises water level] |
Monoculture | Forming uniform, same crop: reduces diversity heavily, genetic erosion |
Selective Breeding | Force mating between certain specimen: reduces genetic diversity |
Genetic Modification | "Superior" forms can be made; less variation amongst species |
Diatoms | Biodiverse algae, diversity increases when it's colder [can use fossils] |
Ecosystems of the past | Pollen fossilises easily. Diversity of pollen used to indicate diversity of the ecosystem |