Effect of hydroseeding components on the germination of Mediterranean native plant species

An understanding of the processes involved in plant succession is pivotal in achieving an effective site restoration. In a former limestone quarry (northeastern Italy), we explored the effects of a technical reclamation on the plant community using changes in cover of vegetation layers and two sensitive plant traits (i.e. exotic status and life span), with a chronosequence approach. Four reclaimed areas of different ages (from 8 to 35 years old) and natural vegetation in the surroundings were investigated with seven permanent plots each, for a total of 35. Changes in vegetation layers and species richness of both exotic status and life span were analyzed by generalized linear (mixed) models. Relations with plant community assembly were also considered, using a multivariate approach. Both vegetation layers and plant traits were affected by the age of reclaimed areas, evidencing the main changes in plant succession. Annual and exotic species decreased toward the mature stages of reclamation and target vegetation, whereas overall plant diversity (species richness) was stable. Our findings show that both vegetation layer changes and plant traits can be used to assess the degree to which reclamation efforts produce results that approach the restoration of a natural vegetation reference. Implementation of management practices aimed at favoring native perennial species (e.g. appropriate seed mixtures, mowing, tree, and shrub planting) could limit weed-control efforts, representing a reasonable trade-off between biodiversity promotion and invasive plant control

Section: Introductionmentioning

confidence: 99%

Vegetation structure, species life span, and exotic status elucidate plant succession in a limestone quarry reclamation

Boscutti

Vianello

Bozzato³

et al. 2016

“…There seems little potential, therefore, to expect long‐term, natural ALH recovery on the many kaolinite open cast mines located in regions where this habitat is most common, and especially where restoration occurs alongside active mining. Instead, and like many OCM sites globally, heathland restoration can likely only be facilitated by further interventions after mining operations cease (Holmes : Benigno et al ; Clemente et al ; Glen et al ).…”

Section: Discussionmentioning

confidence: 99%

“…These include: (1) low soil pH (2.8–3.9; Clarke ), (2) low soil nutrient content (exchangeable calcium 80–159 μg Ca/g, exchangeable phosphorus <10 μg P/g soil; Clarke ), (3) propagule supply of dominant dwarf ericoid plants, and (4) management to prevent succession to woodland (Kleijn et al ; Martinez‐Ruiz et al ; Newton et al ). On this basis, many different restoration techniques have been tested (Pywell et al ; Clemente et al ) but these can be categorized into two classes: those involving soil amelioration (e.g. nutrient addition, overturning) and those involving the selective addition of plants or seeds (Allison & Ausden ; Walker et al ; Pywell et al ; Glen et al ).…”

Section: Introductionmentioning

confidence: 99%

Chronosequence of former kaolinite open cast mines suggests active intervention is required for the restoration of Atlantic heathland

Lane

Hanley

Lunt

et al. 2020

Atlantic lowland heath (ALH) is a priority conservation habitat in Western Europe, but restoration efforts have met with mixed success due to the complexity associated with replicating establishment conditions. By virtue of their impoverished, often acidic soils and geographic location in areas naturally occupied by ALH communities, former kaolinite mine sites may offer an excellent opportunity for heathland restoration. Using a chronosequence of former open cast kaolinite mines in South West England (0, 2, 27, and 150 years since mining ceased), we determined the ability of ALH vegetation and soils to reestablish naturally and in addition, for the three youngest sites, how the reinstatement of stored overburden affected heathland regeneration. Analysis of soil characteristics revealed major differences in the levels of acidity, organic content, and fertility between abandoned kaolinite sites and a nearby natural reference heath. Even 150 years after mining ceased, concentrations of all major soil nutrients and organic content were lower, and pH higher, than undisturbed ALH. The reinstatement of overburden did little to improve soil quality, since all former kaolinite sites were dominated by mesotrophic grasses, rather than species characteristic of the target ALH community. We conclude that to maximize the potential of former open cast kaolinite sites for ALH reestablishment, changes in pre-and postrestoration management are required. These include modification of how overburden is stockpiled, while the addition of organic material, microbial communities, and sulfur (to reduce soil pH) to reinstated overburden are likely also essential interventions to facilitate successful ALH establishment.

“…The success of hydroseeding was therefore limited, as sown species only represented a small fraction of the total plant cover (except for Festuca arundinacea ). The use of native rather than fast‐growing, commercial species has been encouraged for the restoration of degraded areas, although some authors have reported limitations to the recruitment of native species in hydroseeding mixtures (Oliveira et al ; Clemente et al ). Nevertheless, from an ecological point of view, the use of native species in restoration projects presents numerous advantages, such as the preservation of genetic integrity, conservation of local diversity, and the enhancement of natural colonization (Bochet et al ; García‐Palacios et al ).…”

Section: Discussionmentioning

confidence: 99%

A tale of two green walls: a functional trait approach to assess vegetation establishment on restored steep slopes

Monteiro

Brilhante

Domingues

et al. 2020

Green walls (GWs) have been increasingly recognized as an important restoration technique for steep slopes resulting from quarrying activities or major infrastructure construction projects. In practice, GW irrigation is considered essential, although studies evaluating vegetation establishment under different irrigation regimes are lacking. Besides taxonomic metrics, functional diversity measures were used to compare the diversity and composition of plant communities of two hydroseeded GWs, with different irrigation regimes (irrigated vs. low-irrigated). The studied GWs were installed in Peneda-Gerês National Park (NW Portugal) to minimize the visual impact of shotcrete walls, along a road infrastructure, and promote their ecological restoration. Species' cover was recorded 3 years after installation. Species were classified according to their growth form, life form, and life strategy. Despite hydroseeding approximately 57 species, GW vegetation was dominated by spontaneous species, particularly acrocarpous mosses, regardless of irrigation regime. Species and functional richness were higher under irrigated conditions, while no differences were observed for species diversity and functional dispersion. Functional trait composition did not differ between GWs, indicating that both systems potentially provide the same ecosystem functions and services. Our results also suggest that spontaneous species colonizing GWs are highly adapted to local environmental conditions, given their dominance in both irrigated and low-irrigated communities. Overall, irrigation did not affect the structure and functioning of GW communities, only their redundancy, since more species exhibiting similar traits were established in the irrigated GW. Therefore, our findings suggest that low-irrigated GWs, hydroseeded with native species, represent a more cost-effective solution to reduce the ecological impacts of steep slopes. Implications for Practice• Green wall irrigation promotes the establishment of plant communities with higher (species and functional) richness, without changes in functional composition. • Practitioners should consider hydroseeding green walls with native species (both vascular plants and bryophytes), in order to promote the provision of multiple ecosystem services and the conservation of local diversity. • On green wall systems, spontaneous colonization is a key component of community assembly, especially in areas surrounded by natural vegetation. As such, under favorable environmental conditions, the use of hydroseeding can be minimized. • Extensive, low-irrigated green walls represent an innovative solution for the ecological restoration of steep slopes.