This module has been created with the purpose of constituting a space for reflexion on the dynamics and the structure of the world population and its environmental implications, and especially on the sustainable development.

Therefore, this module presents three main sections:

• In the first section, the evolution of the world population is being analysed from a demographic point of view, making reference to quantitative and qualitative aspects, that is, volume and age/sex structure reflected in the population pyramids.
• In the second section, the regional differences of the world population distribution are being analysed from a geographical angle.
• Lastly, the third section, analyses the environmental implications of the dynamics and the exposed trends, from the perspective of the environment and the sustainability.

At the end of the module, it can be found a section containing the conclusions, another one containing a brief question paper for the evaluation of the contents acquisition and comprehension, and also a final section containing links of interest.

The information is being presented in a didactic and interactive way; thus, the user is going to find applications which may help him to produce personalised material, as maps, graphics, etc.

A brief introduction on the adopted perspective

As previously said, the central contents of the module are based on the analysis of the world population and its evolution, from both, the demographic and the geographical viewpoint. Nevertheless, although they appear separately, they are two interrelated sciences that complement each other so strongly that their fusion gives birth to a third science, named Population geography or simply Geodemography.

It is reasonable to give a brief explanation of the each science contents. In order to accomplish it, we are going to quote Anna Cabré’s statement:

CShall we start with the introduction, i.e. with the definition of population and settlement. Population is, technically speaking, a stock, a group; that is, a group of people with a certain volume and certain structures which depend on the employed criteria for the analysis of this population. Which science studies the volume and the population structure? It is Demography.

QWhat is the settlement? The settlement is the connection between population and territory, which usually and primarily uses density and distribution criteria. Which science studies the settlement? It is Geography.

However, the mentioned distinction between their study aims is quite questionable. Undoubtedly, the science that studies the population is called demography, as its Greek etymology states: demos (‘people’) and graphia (‘study’). Thus, demography studies the dimension, the structure, the evolution and the general features of the population. The key issue is finding out whether these general features include the spatial ones, i.e. the features which refer to the settlement, the location and the territorial mobility, or they have to be studied by geography.

Accordingly, if geography is the branch of science that studies the spatial distribution of diverse phenomena, especially those related to human activities, we should consider population as one of them, therefore, it belongs to the geographical area of knowledge. As García Ballesteros argued,

[...] (that) without any doubt, geography is interested in the spatial aspects of the societies’ life, that is to say, its aim is to study the space as a creation established by a society, its system of values; traditions; cultural, social and political attitudes; in a few words, the every society’s ideological ground for the motivations and reasons for action. Subsequently, the society’s daily utilization of the space has obviously an impact on the social organisation of this space, hence, geography, in collaboration with other social sciences, has to study it.

In the same way that it occurred in other geographical areas of knowledge ‒especially after the Second World War‒ as in tourism or urbanism, our discipline has developed a branch, specialised in the study of the spatial distribution of the people and their daily activities in the territory, which has been called Population geography. The author himself gives a brief, but complete, definition of this term: ‘branch of human geography that studies the relationships between the nature of the places and the spatial variations in the distribution, composition, migration and growth of the populations’.