Table 1.

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

	PI	Pn	Chlorophyll content (SPAD)	Stomatal conductance (g)	Leaf protein concentration (mg/g FW)	Root protein concentration (mg/g FW)	Foliar N content (%)
English oak
Control	4.3	5.7	48.6	0.48	55.0	22.1	3.17
Tapwater	1.0^*	1.0^*	28.3^*	0.18^*	24.3^*	10.3^*	1.81^*
7.25 g (0.25 oz) N	3.3^ns	2.9^*	34.6^ns	0.30^*	33.7^*	13.8^*	2.25^ns
14.5 g (0.51 oz) N	3.9^ns	4.5^ns	42.5^ns	0.38^ns	43.1^ns	17.5^ns	2.78^ns
29 g (1.02 oz) N	4.0^ns	4.2^ns	44.1^ns	0.39^ns	47.8^ns	16.8^ns	2.90^ns
LSD	1.55	2.28	16.55	0.161	18.90	7.54	1.15
European beech
Control	4.2	5.8	48.9	0.53	33.4	14.8	3.00
Tapwater	0.7^*	1.5^*	18.7^*	0.13^*	18.7^*	4.3^*	1.23^*
7.25 g (0.25 oz) N	1.4^*	2.0^*	21.8^*	0.19^*	20.5^*	5.8^*	1.40^*
14.5 g (0.51 oz) N	2.8^*	2.4^*	30.2^*	0.27^*	26.5^ns	8.9^*	2.59^ns
29 g (1.02 oz) N	3.1^ns	3.0^*	27.6^*	0.22^*	27.2^ns	9.3^*	2.38^ns
LSD	1.18	1.56	14.75	0.129	10.69	3.78	0.900

↵^zMeasurements were made immediately at the cessation of the waterlogging period. Trees 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.