Introduction to Landscape Ecology What Is Landscape Ecology? To answer this question, let’s begin by asking another question; What is ecology? (last revision: 1/8/2003; minor updates 9/28/2004)

What Is Ecology? The word ECOLOGY was coined by Ernst Haeckel in 1869. It is derived from the Greek oikos, meaning "household", "home," or "place to live" and logos, "the study of.“ Haeckel’s definition: "...the investigation of the total relationships of the animal both to its inorganic and its organic environment...“

What Is Ecology? Other definitions I: "...scientific natural history." (Elton 1927) "...the scientific study of the distribution and abundance of animals." (Andrewartha 1961) "...the study of the structure and function of nature" (Odum 1971) "...the study of the adaptations of organisms to their environment" (Emlen 1973) "...the scientific study of the relationships between organisms and their environments" (McNaughton and Wolfe 1979)

What Is Ecology? Other definitions II: "...the scientific study of the interactions that determine the distribution and abundance of organisms." (Krebs 1985) "...the study of the principles which govern temporal and spatial patterns for assemblages of organisms" (Fenchel 1987) "...the study of the relationships between organisms and the totality of the physical and biological factors affecting them or influenced by them" (Pianka 1988) Above is a short list of definitions that have been suggested by any number of authors. Each of these definitions includes some feature that I like. I don’t want to get bogged down in these definitions but the words in bold give you give you some sense of what I feel should be included in a definition.

Collectively, these definitions convey the notion that: The environment influences organisms AND, organisms influence the environment The fact that we are breathing oxygen (generated mostly by the process of photosynthesis) is a rather striking example of the power of organisms to influence the environment  

What do ecologists study? How do ecologists study things? Experimental papers submitted to the journal Ecology between 1980-86 >50% of studies used experimental plots <1m in diameter! >95% used plots <100m in diameter! Peter Karieva is a professor at the university of Washington and for several years, he was the editor of Ecology; this is the main American Journal in the field. During his tenure as editor (during the mid-1980s), just for kicks, he kept track of the characteristics of all experimental papers that were submitted for publication. These experimental papers, by definition, involved some sort of manipulation, this would exclude descriptive papers. This figure summarizes what he found (figure 1 from Karieva and Anderson 1988). You can see from this figure that the overwhelming majority of these papers were based on the study of experimental plots that were one meter or less in diameter!!!! This figure speaks volumes about the problems that scientists face today when we are asked to address real world problems! These are the data that we have to work with in our field today yet nearly all of the really interesting question that we face as scientist and as resource managers deal not with meter square plots, but with much larger scale features. Given that these are the only data we have to work with, how do we take these data and answer questions about the function of ecosystems, the management of large watersheds and National Forests???

Themes in Landscape Ecology: I. Scaling Issues How do we scale up? What is the most appropriate spatial and temporal scale to use when addressing a given question? (see Urban et al. 1987 and others)

Themes in Landscape Ecology: I. Scaling Issues How do we scale up? What is the most appropriate spatial and temporal scale to use when addressing a given question? (see Urban et al. 1987 and others) But wait…..What do we mean by “scale”

Scale: A confusing term This term is used inconsistently throughout the literature. You will need to learn to read between the lines to determine how each author intends to use this term. The Turner et al. text (on reserve) (Table 1.1) defines scale as the “spatial or temporal dimension of an object or process, characterized by both grain and extent.” Note that Table 1.1 in your book defines a number of terms that we will be using throughout the course. You should be sure that you understand all of these terms. All are fair game for the exam!

Scale: A confusing term grain + extent ? Extent: defined (Table 2.1) as “the size of the study area or the duration of time under consideration.” Note the term can refer either to time or space or maybe both. Grain: a potentially confusing term. Defined (Table 2.1) as “the finest level of spatial (or temporal) resolution possible within a given data set.” Be careful! Some authors treat grain and scale as equivalent terms!

Which map is “large scale?” Ask the class to vote on which is “large scale.”

The formal definition of Map scale is counter-intuitive! 1:100,000 1:100 Map ratio 1/100,000 = 0.000001 1/100 = 0.01 The way geographers & cartographers describe these maps. Small scale (map ratio is smaller!) Large scale (map ratio is larger!) The way most people would (incorrectly) describe these maps. Large scale (only large features visible! And large extent.) Small scale (small features visible! And small extent.) A less confusing way to describe these maps Coarse-scale or coarse grained Fine-scale or fine-grained

Scale: which definition? You need to read between the lines to find out! Scale: grain + extent? Maps with large extent are usually coarse-grained; fine-grained maps usually have small extent. Scale: grain only? Large/small Scale: geographer’s definition or common (incorrect) definition? Inconsistent use of this term is rampant in the literature. Learn to deal with this!

Themes in Landscape Ecology: II. The study of larger areas Implicit in the focus on scaling issues is that Landscape ecology deals with the study of larger areas (landscapes) than has been the case in “traditional ecology.” How large is a landscape? No hard and fast rules. “…a kilometers-wide mosaic over which local ecosystems recur” (Forman 1995) A more general definition that does not require an absolute scale: “…..an area that is spatially heterogeneous in at least one factor of interest” (Turner et al. 2001; p. 7)

Themes in Landscape Ecology: III. The real world is patchy Patch: a surface area that differs from its surrounding in nature or appearance (Table 1.1; and see other related terms in this table) Patches can occur in space or time Edge effects matter! Traditionally, ecologists tried to ignore edges. Sample sites located in the middle of large uniform patches of vegetation.

Themes in Landscape Ecology: IV Themes in Landscape Ecology: IV. Analysis of connectivity in patchy environments How does the arrangement and characteristics of patches influence ecosystem processes? Wildfire spread Juvenile dispersal success Seed dispersal success Hydrologic response

Role of humans often ignored when focused on the study of 1m2 plots Themes in Landscape Ecology: V. Explicit consideration of the role of humans Role of humans often ignored when focused on the study of 1m2 plots The role of humans cannot be ignored at the landscape scale (spatial domain) The legacy of human land use can persist for centuries to millennia (time domain) The role of humans in the time domain: legacies. The legacy of human activity must also be considered in the time domain. La Selva Biological Station (Costa Rica): soil chemistry different in undisturbed forest at site of a 2000 yr old village site. Africa: Masai home sites/corrals. Old-growth rainforest in Peru/Columbia-- long history of slash and burn

Themes in Landscape Ecology: VI. Interdisciplinary Ecology, Biology, Computer Science, Geography, Statistics, Aerospace Engineering (remote sensing), Physics For each paper you read this quarter, take a moment to look at the mailing address of the authors. What academic department are they from? What agency? This gives you a hint about the perspective they bring to any given analysis

Tools for Landscape Ecology: I. Computers fast, cheap computers …and they keep getting faster Processing speed closely linked to transistor density. This has been doubling about every 18 months for nearly 40 years (Moore’s law) Common desktop computers capable of gigaFLOPS This makes it possible to use more sophisticated statistical tests, computationally intensive simulation models and take advantage of things like satellite data and GIS. Science 1996. 274:1834

Tools for Landscape Ecology: II. Statistics Shift from parametric statistics (t-test, ANOVA, linear regression) to spatial statistics Geostatistic: exploiting spatial autocorrelation Parametric statistics (t-tests, ANOVA, regression) are very powerful and they’ve been around since the 1930s or so. Their power comes at a cost and that cost includes a very imposing set of assumptions. A key assumption is sample independence. The real world is full of spatial autocorrelation. Since traditional statistical techniques can’t deal with this correlation, you have to go to great lengths to eliminate it in your data collection procedures. In practice, what this means is that you make sure that your samples sites are far enough apart that you don’t have to worry about it. This works, but, wouldn’t it be nice if you could make this spatial correlation work for you? One of the things that we’d like to be able to do with our hard-won data is scale-up; we might want to take our data from those meter-square plots and project our results over a larger area to paint a map of some feature.........expand...... It turns out that gold miners figured out one approach to this a long time ago. ......expand.......Geostats

Tools for Landscape Ecology: III. GIS and Remote Sensing Made possible by improvements in computers These tools have made it possible to work effectively with large spatial data sets (maps). Often used as tools to prepare datasets for use in various models GIS also often used to display and help analyze output from these models. Parametric statistics (t-tests, ANOVA, regression) are very powerful and they’ve been around since the 1930s or so. Their power comes at a cost and that cost includes a very imposing set of assumptions. A key assumption is sample independence. The real world is full of spatial autocorrelation. Since traditional statistical techniques can’t deal with this correlation, you have to go to great lengths to eliminate it in your data collection procedures. In practice, what this means is that you make sure that your samples sites are far enough apart that you don’t have to worry about it. This works, but, wouldn’t it be nice if you could make this spatial correlation work for you? One of the things that we’d like to be able to do with our hard-won data is scale-up; we might want to take our data from those meter-square plots and project our results over a larger area to paint a map of some feature.........expand...... It turns out that gold miners figured out one approach to this a long time ago. ......expand.......Geostats

Tools for Landscape Ecology: IV. Landscape Metrics As with many new fields of study, the early years of landscape ecology (the 1980s) focused on the development of tools to describe landscape patterns These metrics include, patch size, shape, proximity, edge density, dominance, diversity, fractal dimension, and many more Parametric statistics (t-tests, ANOVA, regression) are very powerful and they’ve been around since the 1930s or so. Their power comes at a cost and that cost includes a very imposing set of assumptions. A key assumption is sample independence. The real world is full of spatial autocorrelation. Since traditional statistical techniques can’t deal with this correlation, you have to go to great lengths to eliminate it in your data collection procedures. In practice, what this means is that you make sure that your samples sites are far enough apart that you don’t have to worry about it. This works, but, wouldn’t it be nice if you could make this spatial correlation work for you? One of the things that we’d like to be able to do with our hard-won data is scale-up; we might want to take our data from those meter-square plots and project our results over a larger area to paint a map of some feature.........expand...... It turns out that gold miners figured out one approach to this a long time ago. ......expand.......Geostats

Tools for Landscape Ecology: V. Models These take many forms. We will expand on this in a week or so. Parametric statistics (t-tests, ANOVA, regression) are very powerful and they’ve been around since the 1930s or so. Their power comes at a cost and that cost includes a very imposing set of assumptions. A key assumption is sample independence. The real world is full of spatial autocorrelation. Since traditional statistical techniques can’t deal with this correlation, you have to go to great lengths to eliminate it in your data collection procedures. In practice, what this means is that you make sure that your samples sites are far enough apart that you don’t have to worry about it. This works, but, wouldn’t it be nice if you could make this spatial correlation work for you? One of the things that we’d like to be able to do with our hard-won data is scale-up; we might want to take our data from those meter-square plots and project our results over a larger area to paint a map of some feature.........expand...... It turns out that gold miners figured out one approach to this a long time ago. ......expand.......Geostats

Origins of Landscape Ecology: The European School German biogeographer, Carl Troll coined the term landscape ecology in 1939 Emphasis on typology, classification, nomenclature and mostly concerned with the “built” (human) environment In the U.S., this perspective is most often found in Landscape Architecture, Planning or Design schools rather than in Biology, Environmental Science or Ecology programs On this last point, it is noteworthy that Richard Forman, an american who has been instrumental in founding the american school of LE, is in the Landscape Architecture program at Harvard.

Origins of Landscape Ecology: The American School Also found in Australia and elsewhere, including in Europe Comparatively young; launched by a few meetings in the early 1980s (Risser et al. 1984) More focused on natural or semi-natural systems Much more heavily invested in theory and models Most practitioners are in Biology, Environmental Science, Ecology, Natural Resources or Geography programs or Natural Resources Management Agencies

What is Landscape Ecology? …..focuses on (1) the spatial relationships among landscape elements, (2) the flows of energy, mineral nutrients, and species among the elements, and (3) the ecological dynamics of the landscape mosaic through time (Forman 1983)

What is Landscape Ecology? ….focuses explicitly upon spatial patterns. Specifically, landscape ecology considers the development and dynamics of spatial heterogeneity, spatial and temporal interactions and exchanges across heterogeneous landscapes, influence of spatial heterogeneity on biotic and abiotic processes, and management of spatial heterogeneity (Risser et al. 1984)

What is Landscape Ecology? ….is motivated by a need to understand the development and dynamics of pattern in ecological phenomena, the role of disturbance in ecosystems, and characteristic spatial and temporal scales of ecological events (Urban et al. 1987)

What is Landscape Ecology? ….emphasizes broad spatial scales and the ecological effects of the spatial patterning of ecosystems (Turner 1989) Emphasis on the effects of pattern on process rather than process on pattern And gee, what does she mean by “scale” here?