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Tree holdings provide important socio-economic and environmental benefits, but invasive alien trees can constrain these benefits. However, some invasive alien plants provide both costs and benefits, making management complex due to varied stakeholder perceptions. Using household surveys, the study explored local people's perceptions of Acacia dealbata invasion and clearing in six villages located in upper Tsitsana communal areas, Eastern Cape Province of South Africa. The results suggest that most respondents are aware of A. dealbata invasion but not its invasion status. The respondents valued A. dealbata for its service provision including firewood, construction poles and shade but also cited negative impacts such as loss of grazing land and water. The respondents were aware of the Working for Water clearing programme and reported employment, income, and are awareness of restored grazing land and increased water availability as key clearing benefits. Although some respondents cleared A. dealbata in their homesteads, a small percentage were opposed to clearing due to the perceived loss of benefits. Overall, the study shows conflicting perceptions on the impacts of A. dealbata invasion and clearing, highlighting the value of considering the social dimensions of invasive alien plant species management to avoid conflict generation. [ABSTRACT FROM AUTHOR]

A great deal of effort has been made to clear invasive alien plants in South Africa, yet it remains unclear if the clearing efforts are yielding positive soil and vegetation recovery trajectories. A few short-term studies have been conducted to monitor soil and vegetation recovery after alien plant removal in South Africa, but convincing, long-term monitoring studies are scarce yet needed. We investigated topsoil and vegetation recovery following Eucalyptus grandis removal 14 years ago by Working for Water in Makhanda, Eastern Cape province of South Africa. The detailed topsoil and vegetation surveys were conducted on forty 10 m × 10 m plots that were in paired cleared and natural sites. The results show no significant differences for the measured soil pH, total N, total C, K, Ca, and Na between the cleared and natural sites, an indication that the two sites are becoming similar. Similarly, the gravimetric soil moisture content shows no significant differences between the two sites, although monthly variations are observed. The topsoils in the cleared sites are hydrophobic as compared to those in the natural sites, which are wettable. We observed no significant vegetation diversity differences between the two sites, with native woody species, such as Crassula pellucida and Helichrysum petiolare, frequently occurring in the cleared sites. We recorded low reinvasion by E. grandis and other secondary invaders like Acacia mearnsii and Rubus cuneifolius in the cleared sites. Based on these results, we conclude that 14 years after E. grandis clearing, both topsoil and vegetation recovery are following a positive trajectory towards the natural sites. However, both reinvasion and secondary invasion have the potential to slow down soil and native vegetation recovery. Recommendations such as timeous follow-up clearing and incorporating restoration monitoring in the WfW clearing programme are discussed. [ABSTRACT FROM AUTHOR]

Coastal sand dune ecosystems are subjected to many stress and disturbance factors that are particularly high in the foredunes compared to the backdunes. Although a few studies have been conducted on eastern coastline sand dunes of South Africa, none have examined the relationship between aspect and slope on vegetation composition and soil properties of coastal forest backdunes. Vegetation and soil sampling were conducted in 11 transects, each with four plots measuring 10 × 10 m, located on the seaward and landward sides and on middle and lower slopes of backdunes of Bathurst coastal forest. A total of 39 species were identified, of which 23 were trees and shrubs, thirteen were forbs and three were grasses. The data show that both aspect and slope had limited influence on vegetation community assemblage and soil properties, but had significant effects on individual species distribution. There was a grass-dominated community on the middle slope and a tree- and shrub- dominated community on the lower slope. These two plant communities act as the required coastal forest ecosystem engineer driving variability in soil properties between the slopes, the most prominent being high soil nutrients and moisture in the lower slopes compared to the middle slopes. [ABSTRACT FROM AUTHOR]

The impact of alien tree clearing on soil and vegetation recovery remains largely understudied. This study focused on changes in soil and vegetation properties following Acacia removal. The aim was to quantify the long-term consequences of alien clearing. Paired cleared (old - 15 years; medium - 11 years; recent - 6 years) and uncleared sites were selected along the Palmiet catchment in Eastern Cape Province, South Africa. Various soil physico-chemical properties (soil moisture, pH, P, N, C, K, Na, Ca, Mg and soil repellency) and vegetation diversity measures were studied on 10 m × 10 m plots. Results indicate that measured soil nutrients are significantly ( P < 0.05) lower in cleared than in uncleared sites. However, comparisons among cleared sites alone indicate that soil properties are recovering with older cleared sites having higher ( P < 0.05) nutrients than recent cleared sites. Soils in uncleared sites are more repellent than soil in cleared sites. Vegetation recovery in cleared sites was taking place with older cleared sites having higher native species diversity than recently cleared site. We conclude that the removal of alien plants could have caused a reduction in soil nutrients. However, as native vegetation recovers on cleared sites, soil nutrients are gradually improving. [ABSTRACT FROM AUTHOR]