LECTURE 17 Landscape, Scenery and Environmental values From an airplane, land almost always appears as a mosaic. Mosaic patterns are found at all spatial scales, from submicroscopic to the planet and universe Landscape and scenery Land mosaics are at the human scale, measured in kilometers to hundreds, even thousands, of kilometers thus, landscapes, regions, and continents are three scales of land mosaics andscape and scenery What causes a mosaic? A closed system with no energy input tends toward randomness. Such lack of organization results in a fairly homogeneous mess throughout, and this is expected according to the second law of thermodynamics Without energy input, a system becomes more disorganized But the land is al ways spatially heterogeneous(an uneven, non-random distribution of objects), that is, it al ways has structure Natural disturbance, including fire, tornado, and pest explosions, creates heterogeneity. And human activity, creates patches, corridors, boundaries, and mosaic pattern Various biological processes commonly modify or enhance the patterns But spatial heterogeneity occurs in to flavors A gradient or series of gradients has gradual variation over space in the objects present Thus a gradient has no boundaries, no patches and no corridors, but is still heterogeneous Specifically, three mechanisms create the pattern. Substrate heterogeneity, such as hills, wet spots, and different Like all living systems, the landscape exhibits structure, function and change Since a mosaic at any scale may be composed of patches, corridors, and matrix, they are the basic spatial lements of any pattern on land Landscapes may be of natural or human origin, and thus apply to the spatial pattern of different ecosystems, community types, successional stages, or land uses In landscapes, there is an illustrated change and relationship between space and time Most short-duration changes affect a small area, and most long-term changes affect a large area. This generalized space-time principle is also observed for many biological responses and other ecological attributes scenery Maps have a scale, but here we use the terms fine-scale and broad or coarse scale. The space-time principle implies that phenomena at broad scales are more persistent or stable than those at fine scales Hierarchy theory and cybernetics are the two major approaches in evaluating predictions of scale Hierarchy theory refers to how a system of discrete functional elements or units linked at two or more scales operates. The landscape system is a nested hierarchy with each level containing the levels below it Therefore, to understand the stability of a particular element, a minimum of 3 linkages must be known. The element is linked to the (1)encompassing element at the next higher level (2)nearby elements at the same scale; and (3)component elements at the next lower level In the clustered tradition of scientific specialization, most ecologists think of the world narrowly, as a system of natural environments beleaguered by human activity. Today, less than 10% of the land surface remains in a mostly unchanged state, and only 4% has been set a side in natural reservesLECTURE 17 Landscape, Scenery and Environmental Values 2 From an airplane, land almost always appears as a mosaic. Mosaic patterns are found at all spatial scales, from submicroscopic to the planet and universe. Landscape and scenery Land mosaics are at the ‘human scale’, measured in kilometers to hundreds, even thousands, of kilometers. Thus, landscapes, regions, and continents are three scales of land mosaics. Landscape and scenery What causes a mosaic? A closed system with no energy input tends toward randomness. Such lack of organization results in a fairly homogeneous mess throughout, and this is expected according to the second law of thermodynamics. Without energy input, a system becomes more disorganized. But the land is always spatially heterogeneous (an uneven, non-random distribution of objects), that is, it always has structure. Natural disturbance, including fire, tornado, and pest explosions, creates heterogeneity. And human activity, creates patches, corridors, boundaries, and mosaic pattern. Various biological processes commonly modify or enhance the patterns. But spatial heterogeneity occurs in to flavors. A gradient or series of gradients has gradual variation over space in the objects present. Thus a gradient has no boundaries, no patches and no corridors, but is still heterogeneous. Specifically, three mechanisms create the pattern. Substrate heterogeneity, such as hills, wet spots, and different soil types, causes vegetation patchiness. Like all living systems, the landscape exhibits structure, function and change. Since a mosaic at any scale may be composed of patches, corridors, and matrix, they are the basic spatial elements of any pattern on land. Landscapes may be of natural or human origin, and thus apply to the spatial pattern of different ecosystems, community types, successional stages, or land uses. In landscapes, there is an illustrated change and relationship between space and time. Most short-duration changes affect a small area, and most long-term changes affect a large area. This generalized space-time principle is also observed for many biological responses and other ecological attributes. Landscape and scenery Maps have a scale; but here we use the terms fine-scale and broad or coarse scale. The space-time principle implies that phenomena at broad scales are more persistent or stable than those at fine scales. Hierarchy theory and cybernetics are the two major approaches in evaluating predictions of scale. Hierarchy theory refers to how a system of discrete functional elements or units linked at two or more scales operates. The landscape system is a nested hierarchy with each level containing the levels below it. Therefore, to understand the stability of a particular element, a minimum of 3 linkages must be known. The element is linked to the: (1) encompassing element at the next higher level; (2) nearby elements at the same scale; and (3) component elements at the next lower level. In the clustered tradition of scientific specialization, most ecologists think of the world narrowly, as a system of natural environments beleaguered by human activity. Today, less than 10% of the land surface remains in a mostly unchanged state, and only 4% has been set a side in natural reserves