ver the last two decades, Spain has substantially increased its presence in world science, according to a new Science Watch survey. The graph below, based on figures from the Thomson Scientific National Science Indicators database, shows Spain’s percent share of Thomson-indexed scientific papers between 1981 and 2003. As the graph indicates, papers with at least one author address in Spain accounted for less than 1% of the Thomson database in 1981—some 3,400 papers. By 2003, Spain’s share had grown to exceed 3% of the database, with roughly 24,800 papers. In output, this represents an increase of more than 600% during the 23-year period. 

Spain’s rise in percent share is particularly striking when compared, as in the graph, against a group of selected nations whose recent output approximates that of Spain (according to 1994-2004 figures from Thomson Scientific’s Essential Science Indicators). While the other nations display a consistent share over the period, or (as in the case of the Netherlands) a modest rise, Spain’s increase is clearly the most dramatic.

A closer look at individual fields reveals that Spain made particularly significant strides in its output of space-science papers between 1981 and 2003; Spain’s presence in this field increased from 0.84% of papers in 1981 to 5.72% in 2003. This 5.72% share of Thomson-indexed space-science papers, in fact, is currently Spain’s highest representation in any of the 22 main fields covered in the standard National Science Indicators database. Over the course of the 23 years, Spain also sharply increased its share of papers in agricultural sciences, from 1% of the Thomson database in 1981 to 5.66% in 2003 (thereby placing the field second to space science in terms of current Spanish representation). Next comes mathematics, where Spain upped its percentage of Thomson-indexed papers from 0.52% of the field in 1981 to 5.11% in 2003. Microbiology is next, with Spain accounting for 4.45% of the field, followed by chemistry (4.19%).

Along with tracking the nation’s output of papers, Science Watch evaluated the citation impact of research from Spain over the last two decades. The three graphs at the bottom of this page cover 14 main fields in three broad groupings. In each graph, the relative citation impact (that is, Spain’s citations-per-paper figure versus the world average for the field) is plotted in a series of overlapping five-year periods from 1981 through 2003.

The top graph shows fields in the physical sciences. Here, physics clearly predominates, proceeding from 18% below the world impact average in the 1981-85 span to a mark 24% above in the 1999-2003 period. Spain’s relative-impact score in physics, in fact, is the nation’s highest. Spain’s performance in engineering also tracks upward, winding up 6% above the world average. A similar trend is evident in chemistry, in which the impact of Spain progresses from a 1981-85 mark some 40% below the world cites-per-paper average to a score 1% above.

In the middle graph, covering plant, animal, & earth sciences, the standout is agricultural sciences. Spanish research has consistently exceeded the world impact average in this field in recent years, with a score for the 1999-2003 cumulative period exceeding the world average by 8%. Although the other fields in this group have yet to reach the world mark, all are clearly trending upward in recent years, with Spanish research in plant & animal sciences registering an impact mark just 6% below the world average.

Comparable trends can be seen in the bottom graph, which tracks biomedical fields. Although not yet exceeding the world average, the impact of research from Spain is on the upswing in these areas—most strikingly in clinical medicine, where Spain’s cites-per-paper mark rose from 73% below the world average in the early 1980s to just 4% below in the most recent five-year period. Neurosciences and molecular biology & genetics are also climbing steadily.

As noted above, the accompanying graphs reflect research papers featuring at least one Spain-based author (i.e., including, in many instances, collaborators from other nations). Science Watch also decided to examine recent, high-impact papers exclusively from Spanish authors and institutions. The most-cited such report in the last decade is a 1997 chemistry paper by Avelino Corma of the Universidad Politecnica de Valencia: "From microporous to mesoporous molecular sieve materials and their use in catalysis," (Chem. Rev., 97[6]: 2372-2419, 1997); this paper has been cited more than 900 times. Corma, in fact, appears as author or coauthor on four of Spain’s 10 most-cited reports published since 1994; not surprisingly, he ranks among the current 25 most-cited scientists in the Essential Science Indicators listing for chemistry.

The second-ranked blockbuster of the last 10 years from Spain is "DnaSP version 3: an integrated program for molecular population genetics and molecular evolution analysis," by Julio Rozas and Ricardo Rozas of the Universitat de Barcelona (Bioinformatics, 15(2): 174-5, 1999); this paper has now been cited more than 660 times.