The continental and global inspection of pollen diagrams is interesting for the data consumers who produce general syntheses (Keltner and Grimm, 1994). However, the data producer, who has created a few diagrams from a small geographical region, should also gain some benefits from the computerized database. In a medium-sized country on a small continent--in Poland for example--a palynologist commonly has to compare 5 to 10 diagrams from the vicinity of a particular lake, or examine sites from a 50 km-long mountain, or something on that scale.
As the visualization tool for the POLPAL database (Ralska-Jasiewiczowa and Walanus, 1991; Walanus, 1994), I have produced STV, a Space-Time Visualization program. Figure 1 shows an example of an STV screen, reduced in size, and output in black and white to a laser printer.
In order to use the program, the data owner must simply prepare an additional file with numbers identifying the chronozones to which a given sample belongs. Of course the data author need not be limited to showing chronozones; it may be pollen assemblage zones or anything else one chooses. But the names of the zones must be displayed on the screen for clarity.
One sample may belong to two zones; if doubtful, it will be included in the average percentage calculation for both zones. Taxa to be displayed are chosen after program execution. Any combination of groups of taxa or individual taxa are possible. Of course if too many taxa are shown at once, the cyclograms will be unreadable. One can also display fragments of all diagrams for a given zone and given taxon.
Although the pollen data to be visualized are already in the database, the specific map must be added. That is no problem for the global databases: one has to make 6 (or at most 7) maps, and that is all.
However, in principle, there are infinitely many local or regional maps. One way to resolve the problem might be to create a program to capture maps using scanners or other devices; this would enable the data author to include the map in the database.
But this brings up the other aspect of a database's local nature that I want to emphasize. A few colleagues in Poland have ordered STV, and in the future I expect, perhaps, five more orders. On the basis of simple economy, I have decided to produce maps by myself. Maps already produced are of raster-type, vector-type, and mixed. If color on the original map is essential, summing up black and white images obtained with different gray levels sometimes helps.
My point, of course, is that techniques developed for handling global databases often ignore the needs of the individuals whose work makes them possible.
Ralska-Jasiewiczowa, M. and Walanus, A. 1991. Polish palynological database (POLPAL) in course of building. INQUA - Commission for the Study of the Holocene, Working Group on Data-Handling Methods 5, 1-2.
Walanus, A. 1994. Optimizing taxon codes in pollen counting. INQUA - Commission for the Study of the Holocene, Working Group on Data-Handling Methods 11, 6.