Ecological restoration is beneficial to ecological communities in this era of large‐scale landscape change and ecological disruption. However, restoration outcomes are notoriously variable, which makes fine‐scale decision‐making challenging. This is true for restoration efforts that follow large fires, which are increasingly common as the climate changes. Post‐fire restoration efforts, like tree planting and seeding have shown mixed success, though the causes of the variation in restoration outcomes remain unclear. Abiotic factors such as elevation and fire severity, as well as biotic factors, such as residual canopy cover and abundance of competitive understorey grasses, can vary across a burned area and may all influence the success of restoration efforts to re‐establish trees following forest fires. We examined the effect of these factors on the early seedling establishment of a tree species—māmane ( We found that elevation was of overriding importance, structuring total levels of plant establishment, with fewer seedlings establishing at higher elevations. Residual canopy cover was positively correlated with seedling establishment, while cover by invasive, competitive understorey grasses very weakly positively correlated with increased seedling establishment. Our results point to specific factors structuring plant establishment following a large fire and suggest additional targeted restoration actions within this subtropical system. For example, if greater native woody recruitment is a management goal, then actions could include targeted seed placement at lower elevations where establishment is more likely, increased seeding densities at high elevation where recruitment rates are lower, and/or invasive grass removal prior to seeding. Such actions may result in faster native ecosystem recovery, which is a goal of local land managers.
Agricultural land is being increasingly abandoned on a global scale, with over 200 million hectares recovering from agricultural use. Plant community regeneration differs greatly in structure and composition after agricultural impacts, yet the mechanisms underpinning these dramatic changes are poorly understood. It is critical to determine the relative importance of abiotic and biotic factors that limit plant establishment and success during the recovery process. In particular, below‐ground competition for resources in soils affected by former agricultural uses may play an important role in limiting plant establishment. Yet, below‐ground competition is generally studied less than above‐ground, especially in the context of land‐use history. We compare plant establishment with and without below‐ground competition in the context of a large‐scale experiment manipulating land‐use histories (i.e. with and without a history of agriculture) and restoration of historical vegetation structure (i.e. thinned and unthinned canopy trees) and determine how life stage and the local environment (e.g. soil water holding capacity, vegetation cover) influence this relationship. For three of our four target species, below‐ground competition strongly limited establishment success, but did not interact with land‐use history and canopy thinning directly. Instead, land‐use history and canopy thinning interacted to affect establishment during germination and survival in spring, while below‐ground competition limited growth during the summer. The strength of below‐ground competition was affected by local resources, but the directionality of this relationship depended on agricultural history and canopy thinning.
- PAR ID:
- 10461129
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Journal of Applied Ecology
- Volume:
- 56
- Issue:
- 5
- ISSN:
- 0021-8901
- Format(s):
- Medium: X Size: p. 1140-1151
- Size(s):
- p. 1140-1151
- Sponsoring Org:
- National Science Foundation
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Abstract Sophora chrysophylla )—in a subtropical montane woodland in Hawaiʻi. Following a human‐caused wildfire, we sowed seeds of māmane as part of a restoration effort. We co‐designed a project to examine māmane seedling establishment. -
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Abstract Zoonotic diseases represent 75% of emerging infectious diseases worldwide, and their emergence is mainly attributed to human‐driven changes in landscapes. Land use change, especially the conversion of natural areas to agricultural use, has the potential to impact hosts and vector dynamics, affecting pathogen transmission risk. While these links are becoming better understood, very few studies have investigated the opposite question—how native vegetation restoration affects zoonotic disease outbreaks.
We reviewed the existing evidence linking native vegetation restoration with zoonotic transmission risk, identified knowledge gaps, and, by focusing on tropical areas, proposed forest restoration strategies that could help in limiting the spread of zoonotic diseases.
We identified a large gap in information on the effects of native vegetation restoration on zoonotic diseases, especially within tropical regions. In addition, the few studies that exist do not consider environmental aspects that can affect the outcomes of restoration on disease risk, such as the land use history and landscape structural characteristics (as composition and configuration of native habitats). Our conceptual framework raises two important points: (1) the effects of forest restoration may depend on the context of the existing landscape, especially the percentage of native vegetation existing at the beginning of the restoration; and (2) these effects will also be dependent on the spatial arrangement of the restored area within the existing landscape. Furthermore, we propose important topics to be studied in the coming years to integrate zoonotic disease risk as a criterion in restoration planning.
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Abstract Applied nucleation, mostly based upon planting tree islands, has been proposed as a cost‐effective strategy to meet ambitious global forest and landscape restoration targets.
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Our results indicate that applied nucleation and plantation restoration strategies are similarly effective in enhancing the recovery of most floral and faunal groups, vegetation structure and ecosystem functions, as compared to natural regeneration.
Seed dispersal and woody recruitment are higher in applied nucleation and plantation than natural regeneration treatments; canopy cover has increased substantially in both natural regeneration and applied nucleation treatments; and mortality of planted N‐fixing tree species has increased in recent years. These trends have led to rapid changes in vegetation composition and structure and nutrient cycling.
The applied nucleation strategy is cheaper than mixed‐species tree plantations, but there may be social obstacles to implementing this technique in agricultural landscapes, such as perceptions that the land is not being used productively.
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Abstract During the “decade on restoration,” we must understand how to reliably re‐establish native plant populations. When establishing populations through seed addition, practitioners often prioritize obtaining seed from locations geographically near the restoration site (i.e. “local seed sourcing”). They are assumed to be under similar environmental conditions to the restoration site and should establish more robust plant populations and preserve local biotic interactions better than seeds sourced from further away. However, this assumption remains virtually untested in realistic restoration settings and the importance of seed sourcing, relative to other factors such as seeding rate and management regimes, is unclear.
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