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More widespread alien tree species do not have larger impacts on regeneration of native tree species in a tropical forest reserve.

ABSTRACT: There is insufficient information regarding the factors affecting the environmental impacts of alien species. In particular, little is known about whether there is any relationship between the invasiveness (establishment and spread) of an introduced species and its per capita impact. We experimentally assessed the relationship between the extent of spread of up to 29 alien plant species and their impact on recruitment of native tree species in Amani Botanical Garden, Tanzania. We also studied the effects of allelochemicals of selected alien on native plant species to assess potential mechanisms of impact. We found no relationship between the extent of spread of an alien tree species and their impact on seed germination, seedling survival, and seedling communities of native trees in their understory, and no indication that allelochemicals consistently explain their effects on recruitment of the studied species. These results suggest that extent of spread cannot be used as a proxy for impact. Hence, managers should continue assessing both the spread and the impact of alien species when prioritizing alien species for management.

SUBMITTER: Kiswaga SAS

PROVIDER: S-EPMC7297787 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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More widespread alien tree species do not have larger impacts on regeneration of native tree species in a tropical forest reserve.

Kiswaga Samson Aman Samson SAS Mbwambo John Richard JR Shirima Deo D Mndolwa Ahmed S AS Schaffner Urs U Eschen René R

Ecology and evolution 20200412 11

There is insufficient information regarding the factors affecting the environmental impacts of alien species. In particular, little is known about whether there is any relationship between the invasiveness (establishment and spread) of an introduced species and its per capita impact. We experimentally assessed the relationship between the extent of spread of up to 29 alien plant species and their impact on recruitment of native tree species in Amani Botanical Garden, Tanzania. We also studied th ...[more]

PMID: 32551079

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More widespread alien tree species do not have larger impacts on regeneration of native tree species in a tropical forest reserve.

Publications

More widespread alien tree species do not have larger impacts on regeneration of native tree species in a tropical forest reserve.

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