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Losses of grasslands have been largely attributed to widespread land‐use changes, such as conversion to row‐crop agriculture. The remaining tallgrass prairie faces further losses due to biological invasions by non‐native plant species, often with resultant ecosystem degradation. Of critical concern for conservation, restoration of native grasslands has been met with little success following eradication of non‐native plants. In addition to the direct and indirect effects of non‐native invasive plants on beneficial soil microbes, management practices targeting invasive species may also negatively affect subsequent restoration efforts. To assess mechanisms limiting germination and survival of native species and to improve native species establishment, we established six replicate plots of each of the following four treatments: (1) inoculated with freshly collected prairie soil with native seeds; (2) inoculated with steam‐pasteurized soil with native seeds; (3) noninoculated with native seeds; or (4) noninoculated/nonseeded control. Inoculation with whole soil did not improve seed germination; however, addition of whole soil significantly improved native species survival, compared to pasteurized soil or noninoculated treatments. Inoculation with whole soil significantly decreased reestablishment of non‐native invasiveBothriochloa bladhii(Caucasian bluestem); at the end of the growing season, plots receiving whole soil consisted of approximately 30%B. bladhiicover, compared to approximately 80% in plots receiving no soil inoculum. Our results suggest invasion and eradication efforts negatively affect arbuscular mycorrhizal hyphal and spore abundances and soil aggregate stability, and inoculation with locally adapted soil microbial communities can improve metrics of restoration success, including plant species richness and diversity, while decreasing reinvasion by non‐native species.
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Surface mines show little progress towards native species forest restoration following 35 years of passive management after initial reclamation
Abstract Restoration techniques using passive management rely on natural plant community succession after reclamation to return disturbed areas to native ecosystems. This approach is often used in areas affected by mining activity, but effectiveness is variable and depends on the ability of native plants to establish in highly degraded soil and outcompete invasive species. We evaluated the restoration progress of three former surface mines where activity had exposed alkaline glacial till parent material. The mines underwent reclamation (grading, soil compaction, and planting fast‐growing herbaceous species) followed by passive management for 7, 28, and 35 years. At the time of initial restoration planning in the 1980s, native woody species were expected to recolonize the site within 10–20 years. Treating the sites as a chronosequence, we observed that woody vegetation increased inconsistently over this 35‐year timespan. Most of the woody plants present today are invasive species (Elaeagnus umbellataandRhamnus frangula) that are counterproductive to reestablishment of native forest. However, results were not entirely negative, with increased overall native species and decreased exotic species in the older sites, and plant community composition changing somewhat consistently over time. This suggests that succession has been slowed rather than completely arrested, and native herbaceous plants are establishing. The progression of restoration appears to be far slower than expectations during initial planning. Furthermore, native woody plants struggle to establish, whereas invasive woody plants are thriving, raising doubts that passively managed succession can lead to the desired outcome of a native species forest in this significantly degraded habitat.
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- Award ID(s):
- 1834241
- PAR ID:
- 10450938
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Land Degradation & Development
- Volume:
- 32
- Issue:
- 7
- ISSN:
- 1085-3278
- Page Range / eLocation ID:
- p. 2351-2359
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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