Novel leaf-root coordination driven by leaf water storage tissues in mangroves

Abstract

Interactions among root and leaf traits (in particular, leaf hydraulic and leaf economics traits) are fundamental in generating diverse strategies in land plants, yet it remains a knowledge gap in mangrove plants that experiences saline stress distinct from most other vascular plants. Here, we tested the trait relationships in mangrove plants and compared them with typical land plants (non-mangrove). Consistent with non-mangrove plants, leaf hydraulic and economics traits were decoupled in mangrove plants. However, mangrove leaf economics traits correlated strongly with root hydraulic traits, which are normally decoupled in non-mangrove plants. Moreover, we observed a unique scaling relationship between leaf dry mass per area and root hydraulic traits in mangroves. The novel coordination between leaves and roots arises from the wide-presence of leaf water storage tissues in mangroves, and this potentially represents a new paradigm with which we look into the ecology, physiology and evolution of this important vegetation.