Ecosystem Geography From Ecoregions to Sites pdf

[...]... between an ecosystem at one scale and ecosystems at smaller or larger scales must be examined to predict the effects of management Because management occurs at various levels, from national to site-specific, one of the prerequisites for rational ecosystem management is to delineate ecosystems at a level, scale, and intensity appropriate to management levels We therefore need a hierarchical system to permit... Preface to the Second Edition vii Preface to the First Edition Chapter 1 Introduction ix 1 The problems Where are we headed? The ecosystem approach Classification of land as ecosystems Ecosystem- based planning Predicting effects Levels of integration Structure: the basis of classification Need for recognizing ecosystems at various scales Ecosystem geography Do we know enough? Need to delineate ecosystem. .. ecosystems, however, are never closed or impermeable; they are open to transfer of energy and materials to or from other ecosystems The open nature of ecosystem boundaries is important, for even though we may be dealing with a particular ecosystem as a land unit, we must keep in mind that the exchange of material with its surroundings is an important aspect of the ecosystem s operation Figure 1.5 Ecosystems... of ecosystems vary vastly in many ways, including their ability to sustain use impacts A footprint in a rainforest might disappear after half an hour, but in the Antarctic, it might take 10 years To manage ecosystems effectively, we need to delineate their boundaries Ecological land classification refers to an integrated approach that divides landscapes into ecosystem units of various sizes The Ecosystem. .. necessary to make independent inferences about forest, grass- 18 1 Introduction land, and shrubland ecosystems However, the local ecosystem can never be understood fully except in the context of the larger ecosystem that encompasses it For such an understanding, we must view ecosystems in a geographic or spatial hierarchy that reflects how they fit together in the landscape Grouping ecosystems to define... provides the basis of ecosystem mapping 10 1 Introduction Need for Recognizing Ecosystems at Various Scales Historically, ecosystems have been defined as small, homogeneous areas or sites, such as a stand of trees or a meadow There are several reasons for recognizing ecosystems at broader scales as well Where the boundaries of one ecosystem are entirely enclosed by another’s, ecosystems are nested... spatial hierarchy of ecosystems, see Bailey (1985) and Klijn and Udo de Haes (1994) Ecosystem Geography Multiscale analysis of ecosystems pertains to all kinds of land, regardless of jurisdiction or ownership boundaries Many environmental problems cross agency, state, and national boundaries These include air pollution, management of anadromous fisheries (fish that go from ocean to freshwater to spawn), introduction... Microscale: Edaphic-Topoclimatic Differentiation (Sites) 145 Causes of site pattern Slope-aspect and ground conditions Geologic differentiation Topoclimate-soil moisture ecoclimatic grid Human influences on ecosystems and present-day systems Chapter 11 Applications of Ecosystem Geography 169 Determining the mapping units Relationships Examples of useful correlations and applications Significance to ecosystem management... 1.2 Major natural regions From Herbertson (1905) land classification” (Wiken and Ironside 1977) This methodology calls for total integration of landform, lithology, relief, climate, soils, and vegetation Carl Sauer (1925) introduced the term landscape into American geography Geography has progressed in the meantime from the study of landforms, soils, vegetation, and the like to a synoptic consideration... units at various scales As in all branches of geography, emphasis is on the causes behind those patterns Ecosystem geography is, in many ways, related to the emerging 16 1 Introduction Figure 1.9 Boundary between Yellowstone National Park and Targhee National Forest Photograph from Greater Yellowstone Coalition, courtesy of Tim Crawford field in ecology called “landscape ecology” (cf Troll 1971; Leser . change: away from managing single resources to managing ecosystems. From for- est to tundra, to desert, to steppe, the world’s ecosystems vary vastly. To manage.