The research design (Fig. 1) to address the issue of changing environment and its influence on growth was centered on using the available network of the Czech landscape inventory plots (CzechTerra, www.czechterra.cz) and its data on site, trees and soils that had been collected during 2008-2009. We proposed a repeated survey of woody biomass on these plots during 2014-2015, complemented with dendrochronological and isotopic (d¹³C, d¹⁸O) sampling and analysis. This provided the information on actual tree increment and stand production for the past 6-year period, including important auxiliary information related to tree vitality, natural mortality and management interventions. Dendrochronology and isotope analysis provided information on growth pattern in recent history (several decades) and information related to water use and water use efficiency. The project used the available information on climatic variables and nitrogen deposition interpolated to be applicable for the individual locations of the CzechTerra landscape inventory plots for the period 1950-2014. This allowed conducting in-depth correlative and model analysis of the observed current and recent-history growth patterns with key factors affecting growth in trees and forest stands within the statistical landscape grid of the Czech Republic. The analysis considered the effect of site conditions (i.e., soil C/N ratio, exchangeable capacity and acidity, and base saturation, stand age and structure) and altitude. The above described research design offered statistically relevant interpretation at country level and its spectrum of site/growth conditions.

Fig. 1: Research design of the project and its key elements