Recent Advances

 

The invasion of French broom (Teline monspessulana (L.) K.Koch) in south-central Chile is favored by forest fires.

 

Forest fires, common in Mediterranean zones and increasing in central Chile,  favor the permanence of the French broom over native species in areas under high levels of anthropogenic disturbance. This is a consequence of several interacting factors, which determine the success of this exotic species.

On one hand, French broom is able to produce large amounts of seeds, which start to reproduce at an early age. The seeds can remain stored in the soil for years. The high temperatures generated during forest fires stimulate the germination of the seeds, reaching their highest germination rate at temperatures close to 100ºC. French broom rapidly re-colonizes the fields that have been affected by a forest fire.

On the other hand, most of the native tree and shrub species are not adapted to this interaction with forest fires.

Finally, a high amount of fuel (biomass) can accumulate in French broom populations, increasing the spreading rate and intensity of forest fires.

In conclusion, a positive interaction is created between French broom and forest fires, highlighting the need for urgent development of control measures for this species.

 

See articles in Pauchard et al. 2008 PDF

See articles in García et al. 2007 PDF

 

 

Advance of Pinus contorta in a Chilean National Reserve

 

Pines, very important species for the forest industry of many countries, have already been registered as invasive in natural ecosystems, especially in the Southern hemisphere. Within pines, Pinus contorta is considered one of the most aggressive species.

In the Malacahuello National Reserve, we studied the regeneration of this species in sites close to plantations and growing next to native species, such as the emblematic Araucaria araucana.

The regeneration density of P. contorta is even higher than the one found in the original plantations. This natural regeneration affects an area of 78 ha, with plants reaching 1,2 km away from the plantation.

We also determined a positive association between P. contorta and Araucaria. This means that there is a higher number of plants of P. contorta in places where Araucaria is present, decreasing the possibility of Araucaria to establish. Furthermore, we determined a negative association between P. contorta and Ñirre, meaning that in places where there is a higher abundance of Ñirre, the regeneration of P. contorta will decrease. Probably, the high cover of Ñirre decreases light availability.

The ability to reproduce at an early age and consistently, along with the establishment of individuals at great distances from the place of origin, allow us to conclude that P. contorta has a great potential as an invasive species in the natural forests of this area.

 

See the article in. Peña et al. 2008 PDF

 

 

 

Trends and challenges for research in biological invasions in Chile

 

A total of 92 articles and book chapters about biological invasions have been published between 1992 and 2008 in Chile, by different institutions and researchers.

An important number of these studies (24%) is restricted to descriptions about the patterns followed by introduced species. However, in order to improve our understanding and control of the process of biological invasion, we propose to deepen the study of mechanisms that allow or restrict invasions.

Only one of the studies is directly aimed at organizations responsible for fighting biological invasions. This demonstrates the urgency of increasing the number of these kinds of studies in order to contribute to managers and policy makers. 

 

See the article in Quiroz et al. (Aceptado) PDF