We can bring relationship between people and their environment into focus by going back to the beach. The population density on a beach is partly a function of environment quality. Good beaches tend to attract more users, while poor beaches are shunned. Other things such as weather and accessibility being equal, we can relate the capacity of a beach to attract a population to its environmental quality. Even within the area of our photograph , local variations in environmental quality can lead to variations in population and the beach environment as maps.
The study of two or more geographic distributions varying over the same area is a study of spatial covariation , an idea we shall meet repeatedly in this book. When the two maps look alike and the two distributions ‘fit’ one another closely, we say that the two phenomena are associated by area; that is high values for population density in one area correspond with high values for environmental quality in the same area , and vice versa. Other hypothetical cases with little covariation are also illustrated in Figure 1.10.Comparing pairs of maps in this manner often tells us a great deal about the spatial covariation of different phenomena. Distributions can also be compared by statistical methods, but a discussion of these lies outside the scope of this introductory text.
To view the environmental quality of a beach in terms of, say ,its surfing potential is clearly only one possible viewpoint –one strongly influenced by age and nationality of the users. For most of our history our questions would relate more to mundane matters of safe anchorage or shellfish yield than to questions of recreational use. We need then to assume some lens or filter which is placed between people and the environment. This means that what we see in a beach may be determined by our age, our interests, our income , our ethnic background , and so on. The environment provides a range of choices, only some of which have ever been seen. For example, a beach backed by very high dunes may suddenly become an attraction for hang-gliding enthusiasts The environment has not changed: but what we choose to see and do in that environment has.
In this book, we shell spend much of Part1 describing the earth’s environment, and much of Part2 discussing our reaction to it. We shall see there how strongly interpretation of a given environment is influenced by social, cultural ,and technological factors.