Department of Geological Sciences
324 Brook Street
Brown University
Providence, RI 02912
phillip_leduc@brown.edu
jww@brown.edu
thompson_webb_iii@brown.edu
The North American Pollen Database (NAPD) and other pollen databases make pollen data readily available over the Internet, where they can be accessed at such places as the World Data Center A for Paleoclimate at the National Geophysical Data Center run by NOAA (the National Ocean and Atmosphere Administration) in Boulder CO. These databases provide pollen counts, radiocarbon dates, latitudes, longitudes and other information from hundreds of sites with pollen data in North America, Latin America, Europe, and the globe. Accessibility to the data is excellent.
These relational databases are continually maintained and updated and offer data that are stored in standardized tables. These databases are relational because the tables are linked by key fields, such as entity numbers that are unique for each site or variable numbers that are unique for each name of a pollen taxon. The tables can be downloaded as Paradox, Access or ASCII files (check the NOAA web site for more information). Borland Paradox and Microsoft Access are relational database management packages that allow the examination and manipulation of data within these database files but only if the user understands the relationships or links between tables. So, the problem is how to make use of the data in the many linked tables once they are downloaded and available on a personal computer or server. At Brown University, we have worked extensively with data from the NAPD in Paradox tables and have developed a tool kit, called Pollen Analysis Tools (PATools) to aid the display and analysis of the data. Because much of our research centers on the mapping of the pollen data, the focus of PATools is to permit data analysis from many sites in a region or continent.
PATools is a collection of Paradox 7 programs that eliminates the need to analyze the NAPD data structure and enables analysts to extract information from downloaded files through a graphic user interface of pulldown menus (see figure in black-and-white or colour and Table 1). Selections from the menus lead to other interfaces with sets of pushbuttons for selecting a pollen sum and the pollen taxa to display or for performing other analytical tasks with the data. The names of the pulldown options are listed in italics and their functions briefly described in the following paragraphs. Although PATools has been developed for use with the NAPD, it can be and has been adapted to other pollen databases of similar structure.
Table Select Percent Chron Analog
Compare Tables Sum Components Verify Site View Find Analogs
Entities Chronologies
Convert Degrees Display Pollen Pcounts and Test Chronologies
Percents
Number Records Display Sites Interpolate Rank All Chronologies
Percents
Number Samples Build Percent Convert Ages
Report
Table 1. Pulldown Menus and Selections in PATools
(Graphic version)
Depth AgeBP CalBP Sum Picea Abies Pinus Betula Other Other Trees cm. yr. yr. Herbs & Shrubs 205 0 0 540 85.74 0.93 0.37 10.00 0.19 2.78 225 778 887 569 86.29 0.70 0.53 8.26 0.88 3.34 252 1829 2085 325 84.00 2.46 0.62 10.77 0.00 2.15 272 2608 2973 371 78.44 2.16 0.54 15.09 0.54 3.23 292 3386 3860 352 58.24 2.84 0.28 30.68 0.57 7.39 302 3776 4304 316 16.14 6.96 1.90 34.49 4.11 36.39 315 4282 4881 322 18.01 1.86 0.62 18.94 3.11 57.45 322 4554 5192 305 24.92 0.00 0.66 27.54 2.30 44.59 332 4943 5635 491 9.16 0.41 3.46 30.35 15.07 41.55 351 5683 6478 323 7.43 1.86 3.41 50.15 8.98 28.17 358 5956 6789 366 5.19 0.00 1.37 55.74 7.10 30.60 378 6727 7632 331 5.44 0.00 6.04 54.38 10.57 23.56 397 7459 8432 252 1.19 0.00 2.78 67.46 8.73 19.84 418 8268 9315 197 0.51 0.00 5.58 57.87 10.66 25.38 438 9039 10156 134 1.49 0.00 3.73 55.22 17.91 21.64Table 2. Pollen Percentage Table with Depths, Estimated Dates, Pollen Sum and Percents (Graphic version)
Entity Chron Default Chron Prepared Date Model No. No. Chron Name By Prepared 193 1 Y COHMAP chron# 4 COHMAP 0000-00-00 linear interpolationTable 3. Chronology Table (Graphic version)
Entity Chron Sample Depth Thickness Age Age Up Age Lo R No. No. No. CM yr. yr. yr. Code 193 1 1 205 0 50 -50 TOP 193 1 2 359 5995 6050 5940 C14 193 1 3 458 9810 9930 9690 C14Table 4. Age Basis Table with Radiocarbon Dates and their Depths and Core Top Date (Graphic version)
Entity Depth AgeBP CalBP Sum Picea Abies Pinus Betula Other Other Trees No. CM yr. yr. Herbs & Shrubs 193 205.00 0 0 100 85.74 0.93 0.37 10.00 0.19 2.78 193 230.70 1000 1140 100 85.81 1.07 0.55 8.79 0.69 3.09 193 256.39 2000 2280 100 82.78 2.39 0.60 11.72 0.12 2.39 193 282.08 3000 3420 100 68.26 2.50 0.41 22.95 0.55 5.33 193 307.75 4000 4559 100 16.97 4.70 1.33 27.61 3.67 45.72 193 333.46 5000 5700 100 9.03 0.52 3.46 31.87 14.60 40.52 193 359.14 6000 6837 100 5.21 0.00 1.63 55.66 7.30 30.20 193 385.09 7000 7930 100 3.85 0.00 4.82 59.26 9.89 22.18 193 411.04 8000 9022 100 0.73 0.00 4.65 61.05 10.02 23.55 193 436.99 9000 10113 100 1.44 0.00 3.83 55.36 17.54 21.83Table 5. Interpolated Percentage Table (Graphic version)
Part of PATools is dedicated to study of chronologies (View Chronologies). The user can analyze the chronology at a site by viewing the chronology and age basis tables (Tables 3-4), by ranking the quality of the chronology for a given time slice (Rank All Chronologies), i.e. the number and proximity of bracketing dates, and by testing and modifying chronologies using an interface (Test Chronologies) that instantly shows how adding, removing or modifying dates affects the estimated ages for pollen samples and displays simple age-depth plots.
PATools also uses dissimilarity measures to compare pollen samples and to find potential analogs (Find Analogs). Given pollen samples in two tables, a master "analog" table and a sample table, for which pollen percentages have been calculated using the same pollen sum, PATools will use a selected dissimilarity measure and threshold dissimilarity value to find the samples in the master table that closely match each sample in the sample table. The user can select from eight measures of dissimilarity (Canberra metric, information statistic, Manhattan metric, squared chi squared coefficient, squared chord distance, squared cosine-theta distance, squared Euclidean distance and squared standardized Euclidean distance) and can accept a default threshold value or choose a new one.
In order to check the impact of recent updates to tables in NAPD, PATools has a utility program to compare tables (Compare Tables). These comparisons will reveal differences between the new and old tables for a site if new data have been added, if old data have been deleted, or if tables have been corrected or modified. PATools can also convert between pseudo-decimal and decimal latitude/longitude formats (Convert Degrees), and it can number records and number samples (groups of records) within a table for easier subsequent access to the information (Number Records, Number Samples).
PATools works within the Borland Paradox 7 database management application program for Windows95 and WindowsNT on IBM compatible computers, and it requires only rudimentary knowledge of Paradox. The tool kit is not fully documented and requires a short period of experimentation. (A user guide is being written.) Requests for copies of PATools and questions concerning its use can be sent to Phillip_Leduc@Brown.edu.
For those who do not own a copy of Paradox 7, the Borland international web site, at www.borland.com/bww, suggests where to buy their products. In the United States, Surplus Direct based in Hood River, Oregon, sells Paradox 7 at an academic discount for about $90. To inquire, visit their web site at www.surplusdirect.com then select "Academic" and then "Database", or call (+)1-800-753-7877.