Monitoring of tree responses at different organizational levels

A bud of Norway spruce in winter condition. The bud scales (ss) are closed and the primordial shoot (*) is approximately one thirds of the total length of the bud. Photo: Metla/Sirkka Sutinen.

Environmental circumstances:
Following environmental variables are monitored in the experiments: soil temperature, soil volumetric moisture content, soil oxygen content, air temperature, air humidity, photon flux density (PAR), photoperiod, soil mineral content. Growth processes of roots and shoots from the cellular to the whole-plant level are investigated.

Physiology:
Photosynthesis, transpiration, dark-adapted chlorophyll fluorescence (Fv/Fm) of needles, chlorophyll a and b content of needles, trunk sap flow (Dynamax, Granier), electrical impedance of roots, stems and needles, root hydraulic conductance, water potential and content of needles, ion leakage (pdf) of needles and root, cold hardiness (pdf), carbohydrate content of needles (soluble sugar and starch).

Anatomy:
Microscopic structure of needles, buds (pdf) and roots (pdf) .

Morphology:
Total length and surface area of roots, number of root tips, diameter distribution of roots, specific root length (SRL).

Phenology:
Start and cessation of shoot, needle and root elongation and diameter growth of trunk.

	Mycorrhiza. Photo: Anna Korhonen.

Growth:
Growth dynamics (shoot and needle elongation, diameter growth of trunk, growth of short and long roots), total biomass and its allocation between roots and shoots, shoot biomass in different cohorts, root biomass in different root diameter categories, life time of roots, decomposition of roots, mycorrhizas. See more details in photos.

Nutrient and gas analyses:
Mineral nutrient content of needles, and pH, organic matter content, mineral nutrient content and particle size distribution of soil, dissolved organic carbon and gases reseased from the soil.