Untitled

chaea in ancient oceans. The low abundance
of pristane and phytane is suggestive
of the relatively low abundance of
photosynthetic autotrophs in comparison
with chemosynthetic bacteria in the
Mesoproterozoic oceans in North China.
The sedimentary environmental condition
is suboxic/anoxic, as indicated by
the low value of the Pr/Ph ratio as well
as the presence of abundant sulfurbearing
organic compounds, consistent
with the other geochemical data in North
China and elsewhere in the world. Both
the composition of the primary producers
and the sedimentary environmental
conditions are favorable for the formation
of hydrocarbon source rocks.
古 生 态 学
2010010036
古 新 世 - 始 新 世 热 最 大 值 对 深 海 微 体 底
栖 群 落 结 构 的 影 响 : 利 用 峰 值 顺 序 曲
线 确 定 古 生 态 反 应 = Impact of the Paleocene-Eocene
thermal maximum on
deep-ocean microbenthic community
structure: Using rank-abundance curves
to quantify paleoecological response.
( 英 文 ). Webb A E; Leighton L R; Schellenberg
S A; Landau E A; Thomas E.
Geology, 2009, 37(9): 783-786
Global climate change has often resulted
in extinction events that can be
quantitatively measured by taxonomic
loss but are more difficult to assess in
terms of ecological restructuring. We
use a commonly applied ecological tool,
rank-abundance curves (RACs), to
evaluate the ecological response of benthic
foraminiferal and ostracode communities
to the Paleocene-Eocene thermal
maximum, which may be seen as an
analog for current and future global
warming. RACs are proxies for community
structure, and therefore changes in
the shape of RACs allow inferences to
be drawn about and quantification of
ecological responses. Benthic foraminiferal
communities became increasingly
stressed during the Paleocene-Eocene
thermal maximum, and community reorganization
occurred before the taxonomically
defined extinction horizon. In
contrast, ostracode communities became
less stressed during the same interval,
reinforcing the idea that different groups
of organisms respond differently to extinction
events and global warming. The
decoupling of ecologic impact from
taxonomic impact during the Paleocene-
Eocene thermal maximum reaffirms the
fact that future climate change could
have far-reaching effects on taxa and
ecosystems and proves the importance
of examining both the taxonomic and
ecologic responses of communities during
extinction events. Abundance
2010010037
显 生 宙 底 栖 碳 酸 盐 相 : 以 俄 罗 斯 地 台
石 炭 系 为 例 并 评 述 = Benthic carbonate
facies of the Phanerozoic: Review and
example from the carboniferous of the
Russian platform. ( 英 文 ). Kabanov P B.
Stratigraphy and Geological Correlation,
2009, 17(5): 493-509
General classifications of Phanerozoic
carbonate facies and controlling them
factors are reviewed. Three principal
carbonate factories distinguished by W.
Schlager (2000, 2003) are the tropical
shallow-water, the cool-water, and the
mudmound factories. The general term
for facies associations in the first factory
is photozoan carbonates. The cool-water
factory encompasses environments producing
heterozoan carbonate facies. The
mudmound factory is a non-actualistic
sedimentary system producing moundshape
buildups of non-skeletal microbial
micrites (also termed automicrites). The
benthic carbonate production is controlled
by light, bottom temperature, eutrophication,
siliciclastic influx, and the
evolution of marine ecosystems. The cyclic
alternation of skeletal associations
(“biofacies”) formed under the control
of high-amplitude sea level changes is
exemplified by the Moscovian (Carboniferous)
epeiric carbonates of the East
14