SCY004 : Klirou Kokkinoyia

Slag Scatter and Geobotany

 
View towards Klirou Kokkinoyia from the north. Photograph: Michael Given

Grid reference: 513350/3876300
Cadastral plan: XXIX/62
Aerial photo: 1993, Run 176, No. 13
SIA: None

Klirou Kokkinoyia is situated on a hill on the western edge of the Akaki River alluvial plain, reaching an elevation of 468 m. Its locality name ('Red Place') derives from an area of gossan where modern mining explorations have occurred. Amidst one area of spoil from such exploration is a limited scatter of small fragments of tap slag, typically 2-5 cm in size. The densest slag scatter covers less than 200 m2, and lies on an eroding slope of between 11-20o. The only pottery in the area consisted of four pieces of worn Medieval/Modern coarse ware and a single piece of Medieval sgraffito, none of it associated with the slag scatter. The discrete slag scatter, along with the uncultivated and relatively undisturbed vegetation, made this a suitable location for a geobotanical investigation of potential changes to vegetation patterns caused by the presence of the slag.

The vegetation over the area is a sparse shrubland dominated by Cistus villosus, with grasses (Bromus and Hordeum) as co-dominants. In different quadrats across the slope, subdominants of the community include Thymus, Sarcopoterium and Helichrysum. Vegetation on the site of the slag scatter is a Cistus/Thymus community with exposed bare soil of up to 60%. Sampling units consisting of a transect with four quadrats were laid across the slope (Transect W17). Six other transects totalling eight quadrats were also sampled in the surrounding area, on the slopes above and below the POSI. The cluster analysis using all species variables sorted the sampling units into four clusters and two outliers. Cluster 4 comprised the three quadrats on the subject area, one of which (W17Q2) contained the majority of the slag scatter. The cluster analysis at the community level, by contrast, sorted the sampling units into three clusters plus outliers. The cluster containing the sampling units over the slag scatter was distinctly larger, and included two control quadrats from areas downslope of the site as well as the three over the slag.

Ordination of the clusters from both analyses which contained the quadrat W17Q2 was undertaken using Principle Components Analysis (PCA). Ordination of the clustered sampling units from the community level cluster analysis was regular and showed no significant variation among the sampling units. Ordination of the cluster from the species level cluster analysis, on the other hand, clearly separated quadrat W17Q2 from the adjoining quadrats (W17Q3, W17Q4). It should be noted, however, that this result was based upon a group of only three sampling units. This is smaller than what is generally considered to be the minimum data set, and thus is not a result from which to draw definitive or wide-reaching conclusions.

The most robust conclusion which can be drawn is that while the slag scatter is not indicated by any detectable change in the vegetation community, a very subtle change in the species array across the transect may point to an indicator at this level. It is unlikely, however, that this finding could be translated into species indicators, since the changes involve both the presence (Rhamnus and Pinus (shrub)) and absence (Phagnalon) of species in the sampling unit over the slag scatter when compared across the transect.

The faintness of the species level indicator supports a possible geomorphological explanation for the site occurrence, as suggested by SCSP geomorphologist Jay Noller. The scatter of tap slag appears to have been deposited on the site as a result of erosion of strata on higher slopes. The effects on the local environment are therefore primarily geomorphological, with only a minor effect (if any) on soil chemistry from the 'recently' deposited slag and other ore-related materials. The effects on the soil environment are therefore at a level where individual species are affected (e.g., the emergence of pioneer species which are not necessarily particular indicators), but not yet at a level where community make-up is affected in a detectable way.