Variation in aboveground net primary production of diverse European Pinus sylvestris populations

On range-wide and regional scales, climate and site factors exert control over tree growth, masking the genetic basis of biomass accumulation and allocation. To determine intrinsic population differences in productivity, aboveground net primary production (ANPP) was measured in 16-year-old Scots pine from 19 geographically distinct populations grown in a common garden experiment in central Poland (52°N). The populations originated from the northern (>55°N), central (54-47°N), and southern (<45°N) European range of Scots pine. We calculated ANPP from aboveground growth components, using diameter-based allometric equations developed for this site. Average foliage, aboveground woody and total ANPP differed significantly among populations and were greater for central European populations than for the southern and northern ones. Stocking and total ANPP per tree were positively correlated to stand aboveground biomass (r²≥0.71). The relationship between the latitude of seed origin and ANPP was curvilinear and maximum for populations originating near the planting site (52°N). ANPP declined in populations with increasing longitude eastward from the Atlantic Ocean towards the center of the continent. This study underscores the potentially large genetic control of ANPP and biomass accumulation among diverse Scots pine populations.