Table 2.

Chlorophyll fluorescence (PI), photosynthetic CO2 fixation (Pn), leaf chlorophyll content, stomatal conductance leaf and root protein concentration, and foliar nitrogen (N) content of English oak (Quercus robur L.) and European beech (Fagus sylvatica L.) 10 days after 18 days waterlogging with and without N fertilization.z

PIPnChlorophyll content (SPAD)Stomatal conductance (g)Leaf protein concentration (mg/g FW)Root protein concentration (mg/g FW)Foliar N content (%)
English oak
    Control5.16.050.20.5457.823.53.20
    Tapwater3.4*3.2*37.5*0.30*29.2*14.7*2.55*
    7.25 g (0.25 oz) N4.2ns3.9*44.5ns0.39*38.7*16.0*2.75ns
    14.5 g (0.51 oz) N4.8ns5.7ns51.6ns0.58ns54.9ns22.8ns3.07ns
    29 g (1.02 oz) N5.2ns5.7ns53.7ns0.60ns60.1ns24.9ns3.30ns
    LSD0.911.269.230.07610.383.360.532
European beech
    Control4.45.456.70.6036.115.23.17
    Tapwater2.2*2.1*33.6*0.35*25.7*8.1*2.00*
    7.25 g (0.25 oz) N3.0*3.0*44.5*0.40*28.9ns11.1*2.44*
    14.5 g (0.51 oz) N4.5ns4.3ns48.9ns0.56ns30.5ns13.0ns2.98ns
    29 g (1.02 oz) N3.8ns5.0ns51.1ns0.52ns32.2ns13.5ns3.23ns
    LSD0.751.1010.890.1197.632.700.633
  • zTrees were situated outdoors subject to natural climatic conditions.

  • FW = fresh leaf weight. PI and leaf chlorophyll content, values mean of mean of six trees, five leaves per tree. Pn and stomatal conductance values mean of mean of six trees, two leaves per tree. Leaf, root protein, and foliar N content mean of six trees, two leaves per tree were used and leaves pooled to provide a mean value per tree.

  • *Significantly different from controls according to least significant difference (LSD) at P < 0.05.

  • ns = not significantly different from control value.