Tree-Ring Analysis in Forest Productivity Studies: An Investigation of Growth-Climate Relationships in the New Forest, Hampshire

Abstract

Tree-ring methods were used to study growth-climatic relation- ships of Corsican pine and Douglas fir, in the New Forest, in equal detail to growth relationships with soil and locality factors. Problems of chronology relia- bility and climatic data appropriateness and expression were examined. Short- term local climate recording and associated surveys of stand hydrology and soil moisture conditions were used to monitor the applicability of data from the long-term climate reference station. These studies made interpretation of the dendroclimatic models much easier. Results suggested that climate importantly influenced growth of both species and especially Corsican pine which showed a 61% growth-climatic link for the overall New Forest model. In the more detailed analyses of different soil and area models, moisture and autumn cold- ness were key themes. The latter relationship was a new trend not evident from soil and locality studies. Omission of climatic influences from general growth- environment considerations thus might seriously impede understanding of growth restraints. This contradicted the widely held view that climatic variability was unimportant as a growth-influencing factor, for these conifer species, in a small area, such as the New Forest.