Terrestrial Palaeoecology and Global Change

374 Valentin A. Krassilov. Terrestrial Palaeoecology
b
a
Fig. 149. The Early Palaeocene
post-crisis plant assemblages of
Tsagajan, Amur Province (Krassilov,
1976a): (a) leaf mat of Trochodendroides
with a paniculate infructescence
of the same plant, (b)
a slab association of Taxodium and
Nyssa, the dominants of a wetland
community first appearing at this
level, widespread later on; (c, d)
serrate leaves of Tiliaephyllum, supposedly
representing a pioneer
(post-fire) shrub growth.
c
d
Cyclocarya, Papilionaceophyllum and Celtis among the angiosperms testify to a relatively
high rate modernization in the uplands.
(4) Nysso–Taxodietum with Myrica and Nordenskioldia, dominating the clayey
oxbow facies. This is the earliest occurrence of a bold cypress – black gum – wax
myrtle community surviving over the Tertiary to the present. Nordenskioldia, supposedly
a climber with long drooping racemes, was shed from this type arboreal wetlands in
the Miocene (Manchester et al., 1991).
(5) Gramino–Carexetum, a primeval herbaceous wetland replacing the Mesozoic
fern marshes, with abundant, though taxonomically poorly understood “Arundo” and
“Phragmites” morphotypes as well as the modern-looking Carex-type achenes. This
appears to be an early representative of hydroseral grasslands persistent over the Palaeogene
and supposedly progenitorial both to mesic and xeric grassland types that appeared
later in the Tertiary (IV.2.5).
(6) Limno–Nupharetum, a diverse aquatic community of rooted and floating angiosperms,
with Nuphar, Nymphaeites, Nelumbo, Limnobiophyllum, Potamogeton,