Biogeomorphology

• What is Biogeomorphology

  • The modification of landforms influenced by organisms
  • Life, particularly plants, is closely tied to the evolution and function of earth’s surface processes
  • Over short time scales Earth’s processes have effects on life
• Landform Feedbacks and Biogeomorphology

  • The changes in sediment transport and deposition can influence the disturbance and succession of plant species in an area.
  • Landform feedbacks can influence the community of vegetation in an area. E.g. flooding leads to changes in sedimentation -> change in topography -> change in vegetation -> change in sedimentation
  • Or in river systems where channel form is influenced by bank stability. And which bank stability is influenced by roots holding it together
• Biogeomorphic Processes

  • Bioerosion: Organisms are an agent of weathering and erosion. E.g., fungi, roots, lichen
  • Bioconstruction: Organisms are involved in the landscape production and features of the landscape. E.g., coral reefs
  • Bioturbation: Fauna impacts the sediment dynamics of environments. Animals such as cows, elephants or marmots.
  • In Australia burrowing animals such as echidnas or bilbies improve the soil health by mixing organic matter and breaking through hard soils. By mixing the soil, there is a change in the distribution of plant material, potentially altering fire regimes
• Implications

  • The colonisation of plants influences the patterns of meandering rivers. Plants can be stabilising elements of river banks, but they can also be potential hazards in the river as they impact flow velocity. Plants also help redistribute the sediments, which also impacts the flow of water
  • Beavers
  • There are significant feedbacks between organisms and physical processes. Changes in physical landscapes can lead to a change in organisms, but on the other hand organisms have a strong control on the landscape evolution process
• How organisms affect geomorphology

  • In the presence of engineer species, natural selection operating at the scale of organisms may have consequences for components of ecosystems, particularly physical processes that impact Earth’s surface
  •   In return these modifications of geomorphic processes and landforms often lead to feedback on the ecological characteristics of an ecosystem. And thus to the engineering species themselves or other species
• Engineering Species

  Species that modify sediment or landform dynamics

  BEAVERS  🦫