geophytes, A. arenaria, Leymus arenarius, and Elytrigia junceiforme. The proportion of annuals was still high (46 %). Because of the relatively low elevation
above sea level of most relevées, about 1 m DNN (Fig. 4.4), water was the most
important agent of diaspore dispersal (46 %), and most species are salt tolerant.
Group B2 (6 relevées) represents the next seral stage of ‘‘dune 2’’ and ‘‘dune 3’’
after these dunes had built up to about the same height as that of the initial dune
(Fig. 4.4). The rhizome geophytes, which dominated group B1, were still dominating, but they were accompanied by Ammophila x baltica. The number of
species increased, and the hemicryptophytes, e.g., F. rubra, became the most
important life form, even if their cover was still low. In this group, as well as in the
following groups, wind was the dominating agent for diaspore dispersal.
Fig. 4.6 a Development in the number of species in the permanent plots over time (1979–2002),
with b dune height above the mean sea level, and c the distance to the sea and d total plant cover.
For the correlation, see Table 4.1
Table 4.1 Correlation (r-values for linear trend lines) between the number of plant species in the
permanent plots, and age, height above mean sea level, distance to the sea, and total plant cover
of the plots
Time
Height
Distance
Plant cover
Dune 1a
r = 0.074 ns
r = 0.354 ns
r = 0.138 ns
r = 0.808**
Dune 1b
r = 0.867**
r = 0.539 ns
r = 0.838**
r = 0.845**
Dune 2
r = 0.928**
r = 0.937**
r = 0.935**
r = 0.958**
Dune 3
r = 0.902**
r = 0.871**
r = 0.833**
r = 0.986**
Dune 4
r = 0.792 ns
r = 0.749 ns
r = 0.898 ns
r = 0.997*
Number of observations: dune 1a–3: n = 7–11; dune 4: n = 3–4. Levels of significance: ns
p [ 0.05; *p \ 0.05; **p \ 0.01)
4 Natural Plant Diversity Development on a Man-Made Dune System
57
above sea level of most relevées, about 1 m DNN (Fig. 4.4), water was the most
important agent of diaspore dispersal (46 %), and most species are salt tolerant.
Group B2 (6 relevées) represents the next seral stage of ‘‘dune 2’’ and ‘‘dune 3’’
after these dunes had built up to about the same height as that of the initial dune
(Fig. 4.4). The rhizome geophytes, which dominated group B1, were still dominating, but they were accompanied by Ammophila x baltica. The number of
species increased, and the hemicryptophytes, e.g., F. rubra, became the most
important life form, even if their cover was still low. In this group, as well as in the
following groups, wind was the dominating agent for diaspore dispersal.
Fig. 4.6 a Development in the number of species in the permanent plots over time (1979–2002),
with b dune height above the mean sea level, and c the distance to the sea and d total plant cover.
For the correlation, see Table 4.1
Table 4.1 Correlation (r-values for linear trend lines) between the number of plant species in the
permanent plots, and age, height above mean sea level, distance to the sea, and total plant cover
of the plots
Time
Height
Distance
Plant cover
Dune 1a
r = 0.074 ns
r = 0.354 ns
r = 0.138 ns
r = 0.808**
Dune 1b
r = 0.867**
r = 0.539 ns
r = 0.838**
r = 0.845**
Dune 2
r = 0.928**
r = 0.937**
r = 0.935**
r = 0.958**
Dune 3
r = 0.902**
r = 0.871**
r = 0.833**
r = 0.986**
Dune 4
r = 0.792 ns
r = 0.749 ns
r = 0.898 ns
r = 0.997*
Number of observations: dune 1a–3: n = 7–11; dune 4: n = 3–4. Levels of significance: ns
p [ 0.05; *p \ 0.05; **p \ 0.01)
4 Natural Plant Diversity Development on a Man-Made Dune System
57