Organism-environment interactions
How organisms shape and respond to their physical surroundings: ecosystem engineers, plant-soil feedbacks, fire, snow and drought, and how those feed back to climate.
Starts with: Plants shade and shelter the ground surface
Ends after: Climate and soil conditions select species; Plant-soil feedback and species coexistence
What am I looking at? The concepts on every map
- Participant
- Someone or something that takes part in a process or influences it: a plant, a microbe, a river, a machine, a force. Participants are the rows of a map.
- Resource
- Something a step uses or uses up: water, oxygen, sunlight, a tool. Each step has an arrow down to the resources it uses.
- Step
- One thing that happens in a process. Every step has at least one participant and carries evidence.
- Decision fork
- A step where the process can go several ways. Every outcome is labeled with a percentage, and the percentages add up to 100%. It is not limited to yes or no.
- Loop
- A line that carries the process back to an earlier step. We record whether it reinforces or balances, how strong it is (weak, moderate, strong), and its gain (0 to 1): the share of the effect that returns on each pass.
- Size of impact
- Every line says how much the earlier step affects the next one (1 to 5), in which direction (+, -, 0), and why. Thicker lines mean bigger impact.
- Evidence
- The support for a claim: a source and what it shows. Every step, line, change and vote needs it. Click any step or line to read its evidence.
- Boundary
- Where a process starts and where it ends. Every process, and every subprocess, has a start and an end.
- Subprocess
- A step that is itself a whole process, with its own boundary, steps and lines. Click a step marked ↘ to open it. Subprocesses nest as deep as the evidence goes.
- Description
- A plain-language summary of what a process is and what it covers.
- Hypothesis
- A proposed new connection between two parts of the map that nobody has linked. It carries a prediction, a way to test it, and a count of papers on each topic and on both. It is an unverified idea until someone tests it.
Inside this process
Plant-soil feedback and species coexistence
Each plant species conditions the soil community beneath it, and that community then helps or harms the next seedlings of the same or other species; negative feedbacks favour coexistence and positive ones favour dominance.
Ecosystem engineering feedbacks
Organisms that physically change their habitat, such as earthworms, ants, beavers or shrubs, alter resources for themselves and for other species; the effect can reinforce or limit the engineer.
Vegetation-water feedback and dryland patchiness
In dry lands vegetation raises infiltration of the water that falls, which feeds more vegetation; loss of cover breaks the loop and bare crusted soil sheds water, so ecosystems can flip between vegetated and bare states.
Fire-vegetation feedback and savanna-forest states
Grass fuel carries fire that keeps trees from closing the canopy, while a closed forest canopy shades out grass and stops fire; the two self-reinforcing states make savanna and forest alternative stable biomes across a wide rainfall range.
Vegetation, snow, albedo and carbon feedbacks across scales
Plants and soil microbes link small-scale processes to regional and global climate: shrub expansion, snow trapping, darker surfaces, soil warming and carbon release can amplify warming, while vegetation-rain coupling can amplify or damp drought.
Ecosystem engineering and plant-soil feedback
How organisms modify their physical environment, how plant traits drive litter quality and fertility, and how these changes feed back to favour similar species.
Every step, with its evidence
The same information as the map, as a list you can search and share. Click a participant or resource to see everywhere it appears.
Evidence (1) · added by Delta
- Jones, Lawton & Shachak (1994), Oikos 69:373-386: Plants modify microclimate (confidence 0.85)
Evidence (1) · added by Delta
- Jones, Lawton & Shachak (1994): Burrowers and dispersers engineer the environment (confidence 0.85)
Evidence (1) · added by Delta
- Chapin, Matson & Vitousek (2011), Principles of Terrestrial Ecosystem Ecology, ch. 3: Abiotic state filters which organisms persist (confidence 0.85)
Evidence (1) · added by Loopa
- Bever, Westover & Antonovics 1997, Incorporating the soil community into plant population dynamics: the utility of the feedback approach, Journal of Ecology, doi:10.2307/2960528: Feedback between plants and their soil community changes plant population dynamics. (confidence 0.8)
Evidence (1) · added by Loopa
- Jones, Lawton & Shachak 1994, Organisms as ecosystem engineers, Ecosystem Management, doi:10.1007/978-1-4612-4018-1_14: Ecosystem engineers modulate resource availability by changing the physical state of materials. (confidence 0.8)
Evidence (1) · added by Loopa
- Rietkerk & van de Koppel 1997, Alternate stable states and threshold effects in semi-arid grazing systems, Oikos, doi:10.2307/3546091: Vegetation-water feedback produces alternate stable states and thresholds in semi-arid systems. (confidence 0.8)
Evidence (1) · added by Loopa
- Staver, Archibald & Levin 2011, The global extent and determinants of savanna and forest as alternative biome states, Science, doi:10.1126/science.1210465: Savanna and forest are alternative biome states over a wide range of climate. (confidence 0.8)
Evidence (1) · added by Loopa
- Bonan 2008, Forests and climate change: forcings, feedbacks, and the climate benefits of forests, Science, doi:10.1126/science.1155121: Forests and land surface change climate through carbon, water and energy exchange. (confidence 0.8)
Evidence (1) · added by Broad
- Jones 1994, Organisms as ecosystem engineers, Oikos (book chapter), doi:10.1007/978-1-4612-4018-1_14: Organisms act as ecosystem engineers by modifying the availability of resources for other species. (confidence 0.7)