Landscape ecology addresses the role that spatial configuration or spatial heterogeneity plays in ecology. It assumes that things vary among locations, and the location, as well as the interaction between things, can have important consequences.

 

Spatial Autocorrelation

• Spatial autocorrelation determines whether the distribution of an event across space is correlated with other events or not.

  • First-order process: the patterns develop as a result of a response to an environmental factor (such as soil, slope position, water bodies)

  • Second-order process: the patterns develop as a result of interaction between the objects/ events themselves.

 

Stationarity

• A process is considered stationary is the process that governs the placement of an object or event do not change over time/space.

  • First-order stationary: there is no variation in the intensity over time. (intensity: the mean/rate/… should be the same everywhere)

  • Second-order stationary: there is no interaction between objects or events. For instance, there is no interaction between different topography and elevation.  

 

Process

• Process describes the abiotic conditions, biotic interactions, and distributions.

  • Abiotic conditions include factors like climate, topography, soil, etc.

    • Topography influences rain and radiation variation since different elevation, slope and aspect have different exposure to sunlight. It can also affect wind and fire. Topography is also related to landslide, animal movement etc.

  • Competition and predation are two examples of biotic interaction. Biotic interaction can create spatial patterns, even in completely homogenous space.

  • Disturbance can be natural or human-influenced. Human settlement, land use change leads to disturbance over the environment.

 

Three general causes of spatial pattern

1. Local uniqueness: the unique feature of a place in a space, such as abiotic variability or unique land uses.

2. Phase differences: variation in the spatial pattern resulting from disturbance

3. Dispersal: prevents large landscapes from becoming uniformly covered with a single dominant.

 

Quantification of pattern

Five classes of metrics (out of 55) were identified by Riitters et al. (1995)

1. The number of classes or cover types

2. Texture measures (fine or course patterns)

3. The degree to which patches are compact or dissected

4. Whether patches are linear or planar

5. Whether patch perimeters are complicated or simple in shape

Other landscape metrics include relative richness, dominance, diversity, and connectivity of the landscape.