Noteworthy records of the lichens associated with Juniperus phoenicea L. die-off in El-Jabal El-Akhdar region, NE Libya

El-Jabal El-Akhdar region is the most vegetated area in Libya dominated by a Mediterranean evergreen maquis ; the juniper trees (Juniperus phoenicea L.) consist of about 70-80% of the vegetation cover. These trees suffer a wide die-off phenomenon for a few decades, which put extra pressure on the ecosystems, in addition to climate change and unsustainable management. Notably, this phenomenon in El-Jabal El-Akhdar region is associated with a dense growth of lichens. This study aimed to identify the lichens on the juniper trees and record some ecological notes. According to our results, a total of 15 taxa belonging to six families and eight genera were recognized on the J. phoenicea trees. The main lichen life-forms were crustose, fruticose, and foliose. However, the densest growth was recorded for Ramalina maciformis (Delile) Bory and Tornabea scutellifera (With.) J. R. Laundon., which appear in most of the infected areas. However, Lecanora gr. subfusca (L.) Ach. has dense growth in only a few areas south El-Jabal El-Akhdar region. This needs further investigation to understand why they grow in such a way on the juniper in the study area. The present study provides baseline information for further progressions in understanding Libyan lichens’ species richness and community composition at local and regional scales.Saaed Manam W B, El-Barasi Yacoub M, Shaikhy Ahmed A El-. Noteworthy records of the lichens associated with Juniperus phoenicea L. die-off in El-Jabal El-Akhdar region, NE Libya. In: Ecologia mediterranea, tome 47 n°2, 2021. pp. 41-49

The composition of the soil seedbank and its role in ecosystem dynamics and rehabilitation potential in the arid Tankwa Karoo Region, South Africa

Very few soil seedbank studies have been conducted in South Africa, especially in arid rangelands. Insight into the soil seedbank could therefore improve assessment of rangeland dynamics and enhance rehabilitation efforts. This study aimed to characterise the soil seedbanks in various vegetation types of the Tankwa Karoo National Park, an arid environment in South Africa. At 43 sites soil was sampled twice at the end of spring and the end of autumn, and the composition and structure of aboveground vegetation were described at the peak growth period in spring. Seeds were isolated from the soil samples by means of flotation in a salt solution, seedbank species composition was obtained by seedling germination, and the vegetation was investigated using a line-point survey method. Overall seed density was 8 034 seeds m−2 of which 55% was viable, and the common life-forms were therophytes and chamaephytes. Species richness and diversity were lower in the seedbank compared with those of the vegetation, and the two vegetation spheres were 25% similar. While seedbank composition suggested poor veld condition, there was enough seed density and viability for future regeneration and rehabilitation initiatives. However, this may be impeded by the absence of many perennial species in the soil seedbank.Keywords: arid environment, interpatches, life-form spectra, patches, rangeland condition, species composition, Succulent Karo