Regionalization of the Mexican Gulf of Mexico: A synthetic approach for multipurpose sensitivity analysis

The Gulf of Mexico is an ocean basin with high environmental and economic importance where, inevitably, natural and anthropic disasters will take place. Therefore it is relevant to assess and regionalize its main biological, environmental and socioeconomic characteristics, for both management and theoretical purposes. In order to characterize the variation of this system, we divided the Gulf of Mexico’s exclusive economic zone of Mexico into 2682, 256.2 km2 hexagonal cells grouped within four zones: oceanic, coastal, insular, and inland. In each cell, we assessed 32 biological, ecosystem, and socioeconomic variables. We made a principal component analysis (PCA) for each zone using the standardized variables to detect cell clusters. We found heterogeneity wtihin the four zones, each having significantly different regions. The coastal zone was the most complex because its regions combine environmental and socioeconomic attributes. Using network analysis with PCA results we identified groups of synergistic and antagonistic variables in each zone. In general, we observed that the synergistic variables are proportionally more connected than the antagonistic ones. However, in the oceanic zone, the connectivity of the antagonistic variables was slightly higher than in the other three zones. This study offers a new integrative view of a complex region with high biological and socioeconomic relevance in a global context. These findings can be useful both for applied and academic aims. The link between PCA and network analysis offers a novel approach for identifying the relative importance of regions and finding not obvious connections between variables. This approach can be used in any socioecological system, whether marine or terrestrial, large or small.Author summary: It is essential to characterize simultaneously biotic and socioeconomic attributes in order to achieve a better understanding of a region, whether for theoretical or sustainable management purposes. Also it is important to identify potential interactions (synergistic or antagonistic) between the variables analyzed. These approaches lead us to consider that resource management should include aspects that can be neglected at first glance. The Gulf of Mexico is a basin of great biological and economic importance, where three countries share interests (Cuba, México and the US). So it is important to fully understand the spatial variation and the relative importance of biological and socioeconomic variables involved and how they may interact with each other. In this study we divided the Gulf of Mexico’s exclusive economic zone of Mexico into 2682 hexagonal cells classified in four zones (oceanic, coastal, insular, and inland), where me measured 32 biological and socioeconomic variables. We linked PCA and network analysis in order to characterize spatial heterogeneity and interactions between variables. We found different regions within zones and that variable importance and their interactions differ between zones. This is a proposal that may help to foster a shared approach for the management and conservation of this region.