This study focuses on the following questions: (i) whether reductions in root:shoot ratio have a cost in terms of
nutrient balance of the plant, and (ii) whether changes in resource-allocation patterns are proportional among
different resources. Our approach was to analyse the variations in the allocation pattern induced by soil
waterlogging. A pot experiment was conducted to analyse the effects of waterlogging on biomass, phosphorus (P)
and nitrogen (N) accumulation of Paspalum dilatatum and Danthonia montevidensis, two waterlogging-tolerant
grasses. When changing from oxic to anoxic conditions, a common response of these and other waterlogging-tolerant grasses is a reduction in allocation to below-ground resources. It was observed that (i) the reduction in
root:shoot ratio caused by waterlogging did not have a cost in terms of capacity for nutrient uptake; (ii) resource
partitioning within aerial parts was less sensitive to treatments than partitioning between roots and shoots; and
(iii) biomass does not appear to be a useful currency for evaluating nutrient-allocation patterns, as the allocation
of P and N was inadequately represented by biomass. The results presented here indicate that the existence of
compensation mechanisms reduces the predictive value of the partition of resources for the capacity of plants to
acquire resources. Data on the allocation of nutrients in relation to biomass suggest that the assumptions of
independence in the allocation pattern between biomass and limiting nutrients under the effects of environmental
factors can be extended.