Natural Areas Conference 2003 - Madison, Wisconsin
WESTERN PONDEROSA PINE NATURAL AREAS: ANOTHER LOOK AT THE LANDSCAPE ECOLOGY OF FIRE
| William L. Baker | |  |
The prevailing image of western ponderosa pine forests before EuroAmerican settlement is one of great beauty, if some monotony. Large, widely-spaced old-growth trees or clumps of trees are thought to have occurred in vast park-like groves with a grassy understory. This structure is thought to have been maintained by frequent, large surface fires that swept away most young trees. However, in the Colorado Front Range and the Black Hills of Wyoming and South Dakota, new research suggests this concept does not fit the ecology of these forests, which naturally had a richer and more diverse spatial structure from landscape-scale variation in the severity of fire and other disturbances. Moreover, in much of the West, I suggest that past research has missed the possibility of similar landscape-scale variation in fires and other natural disturbances by assuming the image of a park-like forest is correct everywhere. Evidence is actually weak or absent in most places, and errors in setting restoration goals can be significant if the wrong landscape model is chosen–uniformly thinning landscapes subject to variable fire severity to attempt to reduce fire severity would not restore the natural landscape. Moreover, the visual simplicity of ponderosa pine landscapes is deceiving, and there likely are more models to be discovered. Researchers and managers can only identify the correct model or new models in ponderosa pine landscapes by sampling and analysis at the landscape scale.
Natural Areas Conference 2003 - Madison, Wisconsin
INTRODUCTION TO LANDSCAPE ECOLOGY
| Jeffrey A. (Jeff) Cardille | |  |
Landscape ecology focuses on the interactions between spatial patterns and ecological processes, and thus can be of great use to natural resource managers. Increasing interest in broad-scale environmental issues and land management, the advent of GIS and availability of remotely sensed imagery, and inexpensive high-powered computing have greatly increased our ability to consider the impact of spatial heterogeneity on our ecological understanding. How will the configuration of a timber harvest encourage or inhibit movement of animals along corridors? Which arrangements of land cover types might allow tree species to migrate during future climate changes? How do the spatial patterns of suburban development influence nutrient uptake in wetlands? These questions, in which spatial pattern is believed to influence some process of interest, are the sorts of problems addressed by landscape ecologists. This presentation introduces the key approaches and terminology in the discipline of landscape ecology. With a focus on providing a basic familiarity with common terms and concepts, we describe the ideas often encountered in landscape ecology studies: scale, grain, extent, edges between habitat types, land cover classifications, patches, corridors, and spatial heterogeneity.