National inventories of alien plants species in developing countries: Advantages and disadvantages of using herbarium records

Background/Question/Methods

There is an urgent need for comprehensive national databases on alien plant species, especially in developing countries. Although, plant invasions are considered a threat to biodiversity, they have been poorly studied and not considered a conservation priority in South America. We assessed alien plant distribution in Chile using a herbarium alien plant database.  We analyzed the implications of using herbarium records to develop national databases of alien plants. We used herbarium records to assemble a comprehensive national database of alien plants. We calculated the number of alien and native species and specimens recorded in Chile (10 x 10 km cell). We evaluated sampling efforts and tested for relationships between alien and native specimens, as well as spatial patterns along the latitudinal gradient.

Results/Conclusions

We recorded 743 alien plants. Alien and native species richness was positively correlated. Alien plants were mostly collected in central Chile, with few species collected in both the extreme north and south. Native plants were strongly collected in central Chile, as well as in both extremes of the country. Areas of high number of alien and native species are associated to large cities or herbarium locations. Overall, the collection of native plants is more diverse than the collection of alien plants. Alien and native plants followed the same pattern of accumulation along the latitudinal gradient, with native plants being relatively more collected than alien plants. Herbarium records provide valuable baseline information to evaluate plant species distribution. However, there are important gaps in this database, (e.g. variable sampling effort for alien and native plants, incomplete information on life-history traits). Given scientists and land managers increasing demand for baseline information and the high cost of collecting such data in developing countries, herbarium records should be used more frequently for research and management of plant invasions. Funded by Conicyt PFB-23 and ICM P05-002.

Keywords: botanical records, database, invasive species, non-native plant, plant richness, Chile.