Seasonal dynamics of macronutrients in aboveground biomass of two herb-layer species in a beech forest

Abstract

The content of six macronutrients (N, P, K, S, Ca, Mg) in the aboveground biomass of two forest plants representing different life forms (Carex pilosa, a hemicryptophyte, and Dentaria bulbifera, a geophyte) was analysed in relation to selected phenological phases. The ability of the plants to accumulate nutrients from the soil into the biomass was studied using transfer coefficients (TCs). Additionally, we examined the temporal changes in nutrient ratios for both species. The study was performed in a beech ecosystem in central Slovakia (Kremnicke vrchy Mountains). The content of available nutrients in the soil (Eutric Cambisol) decreased as follows: N > Ca > S > Mg > K > P. A higher ability to accumulate all elements into the biomass was found for Dentaria bulbifera in comparison to Carex pilosa. We found different patterns of nutrient accumulation between Dentaria bulbifera (N > K > S > Ca > Mg > P) and Carex pilosa (K > N > Ca > S > Mg > P). Temporal changes in the content of nutrients were more noticeable in Dentaria bulbifera, especially for N, S and P – the content of these nutrients diminished. On the other hand, the content of K and Ca in Carex pilosa rose over time. For both species, the highest TC was detected in the case of P and K. Clear temporal variability was also revealed ​​in some nutrient ratios, e.g., [N:K] and [Ca:P]. We confirmed that the nutrient content, nutrient ratio and transfer of macronutrients from the soil to plant biomass vary throughout the growing season in relation to the phenological phases of the plants. Similarly, the dynamics of both nutrient content and the accumulation of macronutrients in the biomass are related to the life form of the plant.