Ecological traditions and systems concepts
A second approach to geography is through ecological analysis, which interrelates human and environmental variables and interprets their links. In this type of analysis, geographers shift their emphasis from spatial variation between areas to the relationships within a single, bounded, geographical area. The origins of the idea of geography as the study of the relationships between man and the earth lie in a country where it subsequently played a paradoxically small part in the development of geographical thinking, i.e. Germany. Friedrich Ratzel's views on 'anthropogeography' appear to have had an indirect but important impact on Vidal de la Blache in France, and more particularly upon Ellen Churchill Semple in the United States. Her Inftuences of geographical environment (1911) had a decisive effect in spreading the idea of the study of 'geographical infuences' (physical determinism) as a major goal in geographical study throughout the English-speaking world.