The Establishment and Maintenance of a Species‐Rich Grassland on a Reclaimed Opencast Coal Site

107

The current study was undertaken to evaluate the success of a revegetation program on three sites within the Bauxite Residue Disposal Area at the Aughinish Alumina Ltd. refinery. This was achieved by determining botanical diversity, substrate conditions, and plant uptake. Two sites revegetated in 1999, with and without the use of gypsum, were assessed and compared to a site revegetated in 1997. Compared to an initial 6 species used in seeding, a total of 47 species were recorded growing on the three sites with greatest diversity on the 1997 site. There was limited variation in the residue properties of the three treatments indicating that diversity was most influenced by succession and not substrate conditions. Limited available manganese was found in all treatments and significantly lower exchangeable magnesium in the gypsum-amended treatment. Exchangeable sodium, aluminum, and pH in the substrate were not at levels of concern. Appreciable nitrogen, phosphorus, and potassium were found as a result of a fertilizing program. Dominant species in the 1999 treatments, Holcus lanatus and Trifolium pratense, were analyzed for elemental composition. Compared to previous studies, foliar nitrogen, phosphorus, potassium, and calcium were adequate and sodium levels were low. Manganese and magnesium levels were low, and availability should be assessed as part of the monitoring program. Furthermore, the effect of a fertilizing regime on plant uptake and substrate conditions needs to be assessed.

Section: Discussionmentioning

confidence: 99%

An Evaluation of Revegetation Success on Bauxite Residue

Courtney

Mullen

Harrington

2009

107

“…In addition, manual seed collection is extremely time consuming (Stevenson et al 1995), whereas seed harvesting with vacuum machines has a limited effectiveness and damages the vegetation and the invertebrate communities of the donor site (Stevenson et al 1997). Commercial seed mixtures also lack many of the target species and their ecotypes (Lippitt et al 1994; Chapman & Younger 1995). In contrast, cattle dung sowing has certain advantages.…”

Section: Discussionmentioning

confidence: 99%

Restoration of Species Richness in Abandoned Mediterranean Grasslands: Seeds in Cattle Dung

Traba

Levassor

Peco

2003

Endozoochory has proven to be a highly effective mechanism in the dispersal of viable seeds in Mediterranean grasslands. We studied the effect of cattle dung application on species richness, particularly on the reintroduction of species lost after abandonment. Sown and control plots were monitored for 3 years after dung sowing. We found a significant increase in small‐scale richness, which may be attributed to the treatment, with the inclusion of species detected in the dung and in the grazed pasture. The differences in richness and floristic composition diminished over time. This experiment proves the potential utility of this treatment for the restoration of species richness in abandoned pastures, although supplementary steps are necessary, including further sowing and/or shrub cutting in subsequent years.

“…Alternatively, it might be appropriate to allow one year for turves, whether whole or rotovated, to settle down and become established without grazing or cutting, followed in subsequent years by a July cut with removal of biomass and a second cut in September, or light grazing with cattle where possible. A study comparing cutting and grazing as maintenance regimes on a species‐rich grassland site established on a restored opencast coal site in the north of England ( Chapman & Younger 1995) showed that cutting maintained species richness better than grazing.…”

Section: Discussionmentioning

confidence: 99%

Translocation of Herb‐Rich Grassland from a Site in Wales Prior to Opencast Coal Extraction

Good

Wallace²,

Stevens

et al. 1999

Reinstatement of vegetation to a similar condition to that prior to disturbance is often required in industrial restoration schemes. Seeding with specially prepared seed mixes containing species suited to local soils is often the preferred option on grounds of practicality and cost. Turf translocation is more difficult and costly but, if successful, meets the reinstatement requirement more precisely. In a pilot study at a proposed opencast coal site in Wales, we compared the effectiveness of whole-turf translocation of herb-rich mesic grassland communities, with a less technically demanding and more cost-effective technique involving spreading turf over twice the area at the receiver site and rotovating it into the underlying soil. The translocated whole turf and rotovated turf plots were cut annually and the vegetation removed to simulate grazing that had occurred prior to translocation. Both the whole-turf and rotovated turf transplant techniques gave successful re-establishment of 50% or more of the species originally present. After three years, the cover and species composition were similar in "whole-turf" and "spread and rotovated" plots. This suggests that the "spread and rotovate" tech-nique provides a satisfactory ecological alternative to whole-turf translocation. However, plant communities changed, in some cases substantially, after translocation using either technique. Altered soil hydrology and nutrition combined with the substitution of cutting for grazing are probably the main causes of these changes.