COMPLEXITY, CONNECTANCE AND LINK DENSITY IN CONTINENTAL FOOD WEBS: DISSIMILARITIES IN AQUATIC AND TERRESTRIAL FOOD WEBS AND THEIR HABITATS .

Both terrestrial and aquatic food webs are characterized by similar key parameters: connectance, robustness, and linkage. Ecosystems vary in basic structures and by processes that govern their dynamics and complexity. A study of complexity, connectance and link density in terrestrial and aquatic food webs, was conducted. We used 49 food webs apportioned in 23 terrestrials, 15 lacustrine and 11 rivers. The results revealed that aquatic food webs presented a difference in superiority of average connectance and link density, (p ~ 0.05), depicting an absence of differences in means. A regression test revealed that connectance and link density are inversely correlated in terrestrial food webs and contrary in other habitats, which was the same case for connectance and the average length of chain. We assume that connectance should be positively correlated with other parameters (fluxes and interaction strengths) in terrestrial habitat as its variations were not explained by link density or the average length of chain. This study revealed a higher estimate of connectance in aquatic habitats compared to their terrestrial counterparts. Aquatic habitats are potentially characterized by high values of parameters related to the connection (interactions quality, organisms’ growth, and food web size) while terrestrial ones are more branded by features depicting constancy (productivity, complexity, and diversity). [ABSTRACT FROM AUTHOR]