Double Sampling Methods in Biomass Estimates of Andean Shrubs and Tussocks

ROJO, V.; ARZAMENDIA, Y.; PÉREZ, C.; BALDO, J.; VILÁ, B.

Rangeland Ecology and Management (ex JRM)

SOC RANGE MANAGEMENT

Año: 2017

1550-7424

The natural Andean vegetation environment is themost important resource available to local pastoralist economies.Knowledge of its attributes is vital in assessing ecosystem properties and improves management decision making.However, there is a lack of research on models that estimate species and life-form biomass for the Puna. Wedeveloped a series of models that facilitated the estimation of biomass while avoiding the direct harvesting ofthe most representative Puna steppe plant species in Jujuy, Argentina. The models thus developed are usefultools in the evaluation of changes in ecosystem dynamics through time and space. Allometric equationswere developedfor the dominant shrubs (Baccharis boliviensis, Fabiana densa, Parastrephia quadrangularis, Tetraglochincristatum, Ocyroe armata, and Adesmia sp.) and tussock grasses (Jarava ichu, Festuca crysophylla, and Cenchruschilense). A field record of the maximum diameter, perpendicular diameter, and height of each plant; numberof individuals per plot; and tussock grasses and shrub cover across all vegetation communities was undertaken.Linear regressions including plant measures demonstrated a good fit (R2 N 0.7, P b 0.001) to the biomass forindividual plants and surface area. The predictive equations developed allow for the rapid and accurate estimationof shrub and tussock biomass. This is essential to monitor the effects of grazing for impact assessment of thedifferent management practices and vegetation dynamics.© 2017 The Society for Range Management. Published by Elsevier Inc