Introduction:

Nutrient cycle studies are important to propose sustainable methods in forestry.

Objectives:

To evaluate the reservoirs of N, P, K, Ca and Mg in trees, litter and mineral soil of two managed stands of Pinus montezumae Lamb.; estimate the decomposition rate of litter; and quantify the annual amount of nutrients required for tree growth.

Materials and methods:

The study was conducted in Nanacamilpa, Tlaxcala. The biomass and mass of nutrients in trunk, branches and leaves were estimated with a destructive sampling of 10 trees.

Results and discussion:

Dasometric data, reservoirs and nutrient dynamics were similar in both stands (t, P > 0.05). In mineral soil, the contents of N, P, K, Ca and Mg were 5 419, 68, 1 245, 9 163 and 2 029 kg·ha-1, respectively; and in aerial biomass were 242, 12, 28, 167 and 118 kg·ha-1, respectively. The decomposition rate of leaf-litter was -0.335. Trees require 73 to 81 kg·ha-1·year-1 of N, 5.2 to 5.3 kg·ha-1·year-1 of P and 9.4 to 10 kg·ha-1·year-1 of K to grow.

Conclusion:

Soil nutrients could maintain forest growth for 256 years, but P could be a limiting factor if sustainable harvest practices change.