Aboveground Biomass Partitioning and Utilization in Festuca dolichophylla: Implications for Rangeland Management

Abstract

Peruvian rangelands are dominated by grasses; whose aerial biomass is distributed among blades, culms, sheaths, and inflorescences serving as essential forage for livestock. Effective management of these rangeland require an accurate assessment of biomass utilization to determine carrying capacity properly. Biomass partitioning varies by species, whereas utilization estimation depends on both, species characteristics and methodological approaches. Therefore, this study aimed to evaluate the partitioning and utilization of aboveground biomass in geographically different populations of Festuca dolichophylla under similar conditions, a key grass species in Peruvian rangelands. F. dolichophylla from: Pastales Huando Peasant Community–Huancavelica (Huancavelica-community), Lachocc South American Camelid Research and Development Center of the National University of Huancavelica (Huancavelica-university), Junín, Pasco, and Puno were transplanted to an environment with uniform soil and climate. Aboveground biomass partitioning was analyzed using a linear model analysis of variance with fixed and nested effects, including covariate adjustment, followed by Tukey’s post hoc tests. Biomass utilization was estimated using height–weight relationships, allowing for the evaluation of how plant structure relates to available forage. The Puno population exhibited significantly higher aboveground biomass (P < 0.05) in blades and culms + sheaths, whereas inflorescence biomass did not differ among populations (P > 0.05). In terms of biomass partitioning, no significant differences were observed for inflorescences (P > 0.05); however, the populations of Pasco and Puno were different (P < 0.05). Plants from Pasco allocated a greater proportion of biomass to blades, while those from Puno exhibited a higher allocation to culms + sheaths. Logarithmic regression provided a more accurate model (R² ≥ 0.88) for estimating biomass utilization compared with linear regression (R² ≤ 0.77), with F. dolichophylla population-specific variations. The observed differences in biomass partitioning and utilization highlight the necessity of population-specific management strategies. These findings provide valuable insights for optimizing the sustainable management of rangelands dominated by F. dolichophylla.