Empirical evidence of direct and indirect relations between environmental pressure and conflict

At a time of increased negative effects of environmental change on human systems such as extreme meteorological events, resource scarcity, and refugee crises, it is especially pressing to understand what role environmental pressure plays in increasing the likelihood of violent conflict. We use a comprehensive measure of environmental pressure – Population Biodensity, defined as the ratio of a country’s population to its biocapacity – to study the presence and intensity of conflict in a large dataset including 28 years of of observations for 181 countries, while controlling for the mediating effects of political regime and income. By means of Bayesian structural equation modelling, we found evidence of a significant relation between environmental pressure and both conflict presence and intensity. Moreover, environmental pressure was shown to be the most significant variable influencing the number of casualties in intrastate conflicts when compared to the level of democratisation and national income. These results highlight the importance of the natural environment for social sustainability, peace, and prosperity.