RT info:eu-repo/semantics/doctoralThesis
T1 Efecto de la eficiencia de crecimiento, la competencia y el muestreo en el análisis de la evolución de masas forestales de la península ibérica
A1 Ordóñez Alonso, Ángel Cristóbal
A2 Universidad de Valladolid. Escuela de Doctorado
K1 Bosques y silvicultura
K1 Sampling plot
K1 Parcela de muestreo
K1 Competition
K1 Competencia
K1 Structure
K1 Estructura
K1 Growth efficiency
K1 Eficiencia de crecimiento
K1 31 Ciencias Agrarias
AB Data from the National Forest Inventory are a valuable source of information that has been used both in management and research works. In study I of the thesis and from numerous plots, both observational and synthetic, we have analyzed the efficiency in the prediction of stand variables, such as basal area or number of feet per hectare, as well as the diameter distribution of the inventoried stands. The same is true for plot size in the estimation of diameter distributions. This paper evaluates the behavior of the diameter distributions transformed by the expansion factors to advise with greater certainty the reduction of plot size in large-scale inventories such as the National Forest Inventory. It is possible to reduce the size of the NFI plots to 15 m without losing efficiency in the estimation of the diameter distribution in most of the national territory, although in stands with large diameter trees the inventory design cannot dispense with sampling in the 25 m crown. In stands where the diameter distribution is bimodal or with a spatial distribution in aggregates, it is necessary to consider modifications in the sampling to improve the estimation of the diameter distribution.For the knowledge of the behavior of forest stands it is of vital importance the use of modeling, and therefore the assessment of growth. For this, in study II we used data from almost 200 plots of black pine and Scots pine installed in pure stands and belonging to the same age class to study the spatial distribution and the effect it has on competition through distance-independent indices, the effect of including distance-dependent indices in the growth equation, as well as the method of competitor selection; Delaunay triangulation was the search radius method whose selected neighbors perform best. We also had good results in angle-based competitor selection methods, where neighbors are selected depending on distance and heights relative to the subject tree and reflects the influence on light interception. The best index found was based on crown.Knowledge of individual tree growth efficiency, or growth per unit of resource utilization, can inform silvicultural management strategies to maximize tree and stand growth. In study III we analyzed two sets of even-aged stand plots of common conifer species in central Spain, 106 Scots pine and 92 black pine, to examine the dynamics of the dominance hypothesis, the relationship between stand structure and growth, and the relationship between structure and growth efficiency. Our main results revealed a negative impact of size class uniformity on stand growth in both Scots pine and Mediterranean pine, while the positive effect of tree size on growth efficiency was supported for Mediterranean pine stands but uncertain for Scots pine. At the operational level, our results highlight how thinning intensity is more important than thinning method in Mediterranean pine forests and how thinning can benefit the provision of multiple ecosystem services. We also recommend integrating the effects of dominance on growth in the modeling of individual trees.
YR 2024
FD 2024
LK https://uvadoc.uva.es/handle/10324/71571
UL https://uvadoc.uva.es/handle/10324/71571
LA spa
NO Escuela de Doctorado
DS UVaDOC
RD 27-nov-2024