The invasive cactus Opuntia stricta creates fertility islands in African savannas and benefits from those created by native trees
Abstract The patchy distribution of trees typical of savannas often results in a discontinuous distribution of water, nutrient resources, and microbial communities in soil, commonly referred to as “islands of fertility”. We assessed how this phenomenon may affect the establishment and impact of inva...
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| Format: | Article |
| Language: | English |
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Nature Portfolio
2021-10-01
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| Series: | Scientific Reports |
| Online Access: | https://doi.org/10.1038/s41598-021-99857-x |
| _version_ | 1818938108243083264 |
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| author | Ana Novoa Llewellyn C. Foxcroft Jan-Hendrik Keet Petr Pyšek Johannes J. Le Roux |
| author_facet | Ana Novoa Llewellyn C. Foxcroft Jan-Hendrik Keet Petr Pyšek Johannes J. Le Roux |
| author_sort | Ana Novoa |
| collection | DOAJ |
| description | Abstract The patchy distribution of trees typical of savannas often results in a discontinuous distribution of water, nutrient resources, and microbial communities in soil, commonly referred to as “islands of fertility”. We assessed how this phenomenon may affect the establishment and impact of invasive plants, using the invasion of Opuntia stricta in South Africa’s Kruger National Park as case study. We established uninvaded and O. stricta-invaded plots under the most common woody tree species in the study area (Vachellia nilotica subsp. kraussiana and Spirostachys africana) and in open patches with no tree cover. We then compared soil characteristics, diversity and composition of the soil bacterial communities, and germination performance of O. stricta and native trees between soils collected in each of the established plots. We found that the presence of native trees and invasive O. stricta increases soil water content and nutrients, and the abundance and diversity of bacterial communities, and alters soil bacterial composition. Moreover, the percentage and speed of germination of O. stricta were higher in soils conditioned by native trees compared to soils collected from open patches. Finally, while S. africana and V. nilotica trees appear to germinate equally well in invaded and uninvaded soils, O. stricta had lower and slower germination in invaded soils, suggesting the potential release of phytochemicals by O. stricta to avoid intraspecific competition. These results suggest that the presence of any tree or shrub in savanna ecosystems, regardless of origin (i.e. native or alien), can create favourable conditions for the establishment and growth of other plants. |
| first_indexed | 2024-12-20T06:02:36Z |
| format | Article |
| id | doaj.art-3fc6eba7ddd444ebbe89474ae4b5aed8 |
| institution | Directory Open Access Journal |
| issn | 2045-2322 |
| language | English |
| last_indexed | 2024-12-20T06:02:36Z |
| publishDate | 2021-10-01 |
| publisher | Nature Portfolio |
| record_format | Article |
| series | Scientific Reports |
| spelling | doaj.art-3fc6eba7ddd444ebbe89474ae4b5aed82022-12-21T19:50:52ZengNature PortfolioScientific Reports2045-23222021-10-0111111310.1038/s41598-021-99857-xThe invasive cactus Opuntia stricta creates fertility islands in African savannas and benefits from those created by native treesAna Novoa0Llewellyn C. Foxcroft1Jan-Hendrik Keet2Petr Pyšek3Johannes J. Le Roux4Department of Invasion Ecology, Institute of Botany, Czech Academy of SciencesDepartment of Botany and Zoology, Centre for Invasion Biology, Stellenbosch UniversityDepartment of Botany and Zoology, Centre for Invasion Biology, Stellenbosch UniversityDepartment of Invasion Ecology, Institute of Botany, Czech Academy of SciencesDepartment of Botany and Zoology, Centre for Invasion Biology, Stellenbosch UniversityAbstract The patchy distribution of trees typical of savannas often results in a discontinuous distribution of water, nutrient resources, and microbial communities in soil, commonly referred to as “islands of fertility”. We assessed how this phenomenon may affect the establishment and impact of invasive plants, using the invasion of Opuntia stricta in South Africa’s Kruger National Park as case study. We established uninvaded and O. stricta-invaded plots under the most common woody tree species in the study area (Vachellia nilotica subsp. kraussiana and Spirostachys africana) and in open patches with no tree cover. We then compared soil characteristics, diversity and composition of the soil bacterial communities, and germination performance of O. stricta and native trees between soils collected in each of the established plots. We found that the presence of native trees and invasive O. stricta increases soil water content and nutrients, and the abundance and diversity of bacterial communities, and alters soil bacterial composition. Moreover, the percentage and speed of germination of O. stricta were higher in soils conditioned by native trees compared to soils collected from open patches. Finally, while S. africana and V. nilotica trees appear to germinate equally well in invaded and uninvaded soils, O. stricta had lower and slower germination in invaded soils, suggesting the potential release of phytochemicals by O. stricta to avoid intraspecific competition. These results suggest that the presence of any tree or shrub in savanna ecosystems, regardless of origin (i.e. native or alien), can create favourable conditions for the establishment and growth of other plants.https://doi.org/10.1038/s41598-021-99857-x |
| spellingShingle | Ana Novoa Llewellyn C. Foxcroft Jan-Hendrik Keet Petr Pyšek Johannes J. Le Roux The invasive cactus Opuntia stricta creates fertility islands in African savannas and benefits from those created by native trees Scientific Reports |
| title | The invasive cactus Opuntia stricta creates fertility islands in African savannas and benefits from those created by native trees |
| title_full | The invasive cactus Opuntia stricta creates fertility islands in African savannas and benefits from those created by native trees |
| title_fullStr | The invasive cactus Opuntia stricta creates fertility islands in African savannas and benefits from those created by native trees |
| title_full_unstemmed | The invasive cactus Opuntia stricta creates fertility islands in African savannas and benefits from those created by native trees |
| title_short | The invasive cactus Opuntia stricta creates fertility islands in African savannas and benefits from those created by native trees |
| title_sort | invasive cactus opuntia stricta creates fertility islands in african savannas and benefits from those created by native trees |
| url | https://doi.org/10.1038/s41598-021-99857-x |
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