Fine roots stimulate phosphorus release from leaf litter

Nathielly Martins, who is currently doing her PhD thesisat the National Institute of Amazon Research (INPA) in Manaus, Brazil, just published her first first author paper in the journal Plant and Soil, where she studied the influence of fine roots during leaf litter decomposition.

In many tropical forests growing on nutrient depleted soils it has been observed that plant roots create large root mats intensely intercepting the leaf litter layer. This phenomenom has been interpreted as a strategy of plants to take up scarce nutrient directly from the

decomposing leaves to avoid that they get leached into the soil matrix, which has often a strong potential to adsorb mineral nutrients such as phosphorus, potassium or magnesium.

In her master thesis, Nathielly conducted an intense field experiment, where she excluded roots from colonizing decomposing leaf litter and compared the dynamics to leaf litter that was decomposing with root access. She found that litter mass loss did not change, but phosphorus was lost faster from litter, when roots had access to the litter compared to when roots were excluded. Moreover, she found that the potential rates of an enzyme - acid phosphatase - that is targeting ester-bound phosphates in organic material, was increased when roots were present, highlighting this as a potential strategy of fine roots to increase their acces to potenial scarce nutrients.

Congratulations to Nathielly to the publication of her paper and highest respect for her enthusiasm and passion to investigate and explore nutrient cycling in tropical forests and to have the patience to extremely carefully process this ton of litter and fine root samples!!!!