Environmental Impact of Wood Anatomy

Tree ring growth per year = Age trend per year + Climate signal per year + Unexplained variability + site related disturbance signals + tree-related disturbance signals

Growth is limited by the scarcest resource

1. Cell enlargement : cell division in the cambium

2. Cell wall thickening: water sucks into cells

3. Lignification: in the whole cell wall

• Water is needed for enlargement

• Carbon and temperature to accelerate the process

• Trees growing in dry vs. irrigated sites

• Result: Tracheids greater in dry trees than in irrigaed in scots pine

• Reason: dry trees build very wide cells —> better water transport —> build more efficient cells —> latewood is a waste of resources; invest everything in a few cells

• Having trees of the same genotype in different water conditions

• well watered have bigger vessel diameters and less cells

• 3 treatments of adult trees: irrigated, drought, ambient

• Extreme drought in 2011

• Ring area of irrigated > ambient > droughted

• During extreme drought in 2011 the growth of all 3 is going down buffered by irrigated

• Hydraulic efficiency is going down for all

• Hydraulic safety stays but go down for droughted

• Take the risk to survive —> build bigger cells but smaller cell walls —> reducing safety

• Increment cores (living trees and construction wood)

• Microcores (living trees)

• Stem disks (relict wood)

• Dendrometer (electronic or manual): measure changes in stem circumference

• Stem shrinks in the morning (transpiration faster than Osmosis)

• Sapflow sensors: determine the amount of water that flows through the stem

• Indicate an ealy cold spell in the late season

• Blue latewood band after staining

• Lignification not completed —> interrupted by cold

• Cells are deformed because of lignin stabilization is missing

• Biotic (insects)

• Abiotic (fire)

• Can be accessed by discontinuous time series

• Drop in fiber cell wall thickness due to Euoris occulata larvae outbreaks

• Tree-ring width

• EW LW width

• Max/min density

• Cell dimensions

• Chemical composition

Wood cell meas,within tree rings can be arranged as time series

Can be compared to climate data

if there is a strong correlation —> past climate can be reconstructed

• General wood anatomical type is species specific

• Indicators: different Genotypes and provenances within species are differently affected by climate variability