Possible Early Dry-Land
and Wet-Land Rice Cultivation
in Highland North
Sumatra
BERNARD K. MALONEY
TRADITIONALL
Y POLLEN ANALYSTS have only examined pollen and concentrated in particular upon
what changes in the tree pollen curves indicate about local and regional
vegetation change. Having tracked this, they have made deductions about how
swamp and lake-margin vegetation has varied in relation to natural progression
or retrogression over time and made palaeoclimatic deductions and deductions
about human use of the land. More recently attention has been focused rather
more on what the nonarboreal component of each pollen spectrum reveals, and now
people are beginning to recognize that the pteridophyte record might also
indicate how climate has changed and give signals to possible past
anthropogenic activity. Additionally it is becoming increasingly recognized
that the analyst must do more than attempt to explain the fluctuations in the
pollen and spore records. It is also desirable to count other microfossils that
may be present, and these include the biogenic silica (phytoliths, which only a
very few people can identify expertly), the algae, microfossil charcoal, leaf
cuticular remains, microscopic volcanic ash, and the like. Complete Southeast
Asian pollen diagrams alone often contain a very large number of taxa, many of
which are ecologically uninformative. The Pea Bullok cores to be mentioned
later contained 355 identifiable types in the 70 samples analyzed so far, and
other types not yet found in samples from that site are present in those from
the other three sites that will be mentioned (Pea Sim-sim, Pea Sijajap, and Tao
Sipinggan), despite the fact that they are situated fairly near each other. To
present the full data set to nonexperts would be futile, as the pertinent
information concerning what the records indicate about vegetation change would
be lost in the wealth of technical detail. It is, of course, desirable that the
full data set should either be published or submitted to a data bank and be made
available to other specialists in due course, and I hope to do this when time
permits.
BACA
SELENGKAPNYA: di sini
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