The drivers of environmental change were largely based on the International Union for the Conservation of Nature’s threat classification (more information here). Definitions for the drivers of environmental change are as follows:
Diseases
Harmful pathogens and microbes that are originally found within the ecosystem(s) in question, but have become “out-of-balance” or “released” directly or indirectly due to human activities.
Droughts
Periods in which rainfall falls below the normal range of variation.
Earthquakes
Earthquakes manifest themselves by shaking and displacing or disrupting the ground. They may also cause associated events such as tsunamis, landslides, or even volcanic activity.
Fire
Suppression or increase in fire frequency and/or intensity outside of its natural range of variation.
Flooding
Extreme precipitation events leading to the submergence of dry land.
Habitat modification
Major changes in habitat composition and location, for example deforestation.
Human modification of genetic material
Human altered or transported organisms or genes.
Human movement
Migration by people from one place to another with the intentions of settling, permanently or temporarily in a new location.
Industrial or domestic activities
Non-agricultural human activities including non-consumptive use of resources.
Industrial or domestic construction
Process of constructing a building or infrastructure for industrial or domestic purposes.
Intensive agriculture and aquaculture
Threats from farming and ranching as a result of agricultural expansion and intensification, including silviculture, mariculture and aquaculture (includes the impacts of any fencing around farmed areas).
Invasive species
Harmful plants, animals, pathogens and other microbes not originally found within the ecosystem(s) in question and directly or indirectly introduced and spread into it by human activities.
Landslides
Landslide events leading to geological changes.
Ocean acidification
Changes to the ocean chemistry which occurs when carbon dioxide is absorbed from the atmosphere and reacts with seawater to produce acid.
Ocean current and circulation
Large scale movement of waters in the ocean basins.
Overfishing
The harvesting of aquatic wild animals or plants at a rate that is greater than their capacity for regeneration. Harvesting can occur for commercial, recreation, subsistence, research, or cultural purposes, or for control/persecution reasons; accidental mortality/bycatch are also included.
Overharvesting
The harvesting of plants, fungi, trees and other woody vegetation, and other non-timber/non-animal products at a rate that is greater than their capacity for regeneration. The harvesting can occur for commercial, recreation, subsistence, research or cultural purposes, or for control reasons.
Overhunting
The killing or trapping terrestrial wild animals or animal products at a rate that is greater than their capacity for regeneration. The killing or trapping can occur for commercial, recreation, subsistence, research or cultural purposes, or for control/persecution reasons; includes accidental mortality/bycatch.
Pests
Harmful plants or animals that are originally found within the ecosystem(s) in question, but have become “out-of-balance” or “released” directly or indirectly due to human activities.
Pollution
Threats arising from the introduction of contaminants into the natural environment.
Population changes
Changes in species populations over time and space.
Sea level rise
Increase in global mean sea level as a result of an increase in the volume of water in the world's oceans or heat dilation.
Sea surface temperature
Periods in which sea surface temperatures exceed or go below the normal range of variation.
Storms
Extreme precipitation and/or wind events.
Volcanoes
Volcanic events which may lead to changes in natural capital assets.
Water abstraction
Changing water flow patterns from their natural range of variation due to human activities.
Weather conditions
Weather conditions outside of the natural range of variation.