Beyond the image of narrow patches, corridors are functionally important landscape structures influencing dispersal of plants and animals in the landscape (Haddad et al. Finally, corridors are narrow patches that may act as links or barriers in a landscape. The large proportion of the landscape classified as matrix may have profound influences on the ecological processes in the landscape for example, consider the flow of pesticides from the farmed matrix to the wetland patches in Figure 1. The matrix is the majority of the surrounding landscape (i.e., not the patches) in this case the matrix primarily consists of fields of agricultural crops. In Figure 1, wetlands and perennial grasslands would likely be patches of focal interest for the study of ecological processes. A patch is an area of habitat differing from its surroundings, often the smallest ecologically distinct landscape feature in a landscape mapping and classification system. Examining the map of an area in North Dakota (Figure 1) helps to define important vocabulary and illustrates some typical questions studied by landscape ecologists. Imaging and mapping technology naturally promoted a patch-corridor-matrix approach to landscape ecology. This work was important, not only because it outlined principles, but also because it brought together the North American scientific interest - typically focused on heterogeneity in ecosystems - with more anthropocentric scientific traditions of geography, landscape architecture, and planning, rooted in the long history of landscape alteration in Europe. In 1986, Forman and Godron published their seminal text on landscape ecology. The International Association of Landscape Ecology was formed in 1982. In landscape ecology particularly, a “non-equilibrium” view emerged, that links disturbance in time and space to system structure and function in feedback loops that influence the ecology and evolutionary trajectories in the ecosystems. Landscape ecology specifically recognizes that disturbance, whether anthropogenic or caused by natural processes, creates spatial heterogeneity that is the normal condition of ecosystems. ![]() The technology enhanced a paradigm shift occurring in ecology and the emergence of landscape ecology as a sub-discipline within ecology (Wu & Loucks 1995). Such views of nature and the theory about dynamics led to “equilibrium” concepts (May 1973) that dominated ecological thinking from the 1920s through the 1980s.ĭuring the 1980s, advances in the accessibility of computing, remotely sensed satellite and aerial imagery, development of geographic information systems (GIS, ARC/INFO was first released in 1982), and spatial statistical methods (Fortin & Dale 2005), enabled ecologists to observe and analyze spatial heterogeneity ranging from local habitats to entire continents. But the resulting models treated the environment as spatially homogeneous. Compared to vegetation, where observed change was rather slow, observations of fluctuating populations ranging from bacteria and protozoans in the laboratory to snowshoe hares ( Lepus americanus) in the boreal forest, led scientists to mathematical theories that explicitly focused on temporal dynamics (Kingsland 1995). ![]() ![]() For example, scientists were struck by the relatively consistent associations of plant species and grouped vegetation into community types (Mueller-Dombois & Ellenberg 1974). But early ecologists did not have the technology or concepts to explicitly deal with spatial heterogeneity, so there was a tendency to develop explanations by grouping organisms into uniform and recognizable units. Throughout the history of ecology, scientists have observed variability across time and space in the abiotic and biotic components of ecosystems.
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