Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Urban vegetation change after a hundred years in a tropical city (San
  Jos\'e de Costa Rica)   Urban vegetation is of key importance because a large proportion of the human
population lives in cities. Nevertheless, urban vegetation is understudied
outside central Europe and particularly, little is known about the flora of
tropical Asian, African and Latin American cities. We present an estimate of
how the vegetation has changed in the city of San Jos\'e, Costa Rica, after
about one century, with the repeat photography technique (based on a collection
of 19th and early 20th century photographs by Jos\'e Fidel Trist\'an and
others) and with data from the Costa Rican National Herbarium. We found little
vegetation change in the landscape of San Jos\'e during the 20th century, where
a total of 95 families and 458 species were collected in the late 19th and
early 20th century. The families with most species were Asteraceae, Fabaceae,
Poaceae, Lamiaceae, Euphorbiaceae, Solanaceae, Cyperaceae, Acanthaceae,
Malvaceae, Piperaceae and Verbenaceae. Similar results have been found in
Europe, where the number of plant species often is stable for long periods even
when the individual species vary.

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The categories of this paper are: cond-mat
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The categories of this paper are: cs
3
The categories of this paper are: physics
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The categories of this paper are: dg-ga
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The categories of this paper are: astro-ph
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The categories of this paper are: hep-th
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The categories of this paper are: patt-sol
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The categories of this paper are: nlin
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The categories of this paper are: nucl-ex
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The categories of this paper are: hep-ex
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The categories of this paper are: bayes-an
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The categories of this paper are: nucl-th
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The categories of this paper are: eess
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The categories of this paper are: chao-dyn
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The categories of this paper are: plasm-ph
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The categories of this paper are: cmp-lg