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Scopoli's Shearwater (Calonectris diomedea) is a Procellariiform endemic to the Mediterranean Basin which is considered to be vulnerable in Europe due to recent local declines and its susceptibility to both marine and terrestrial threats. In the 1970s-1980s, its population size was estimated at 57,000-76,000 breeding pairs throughout the Mediterranean Basin, with the largest colony, estimated at 15,000-25,000 pairs, found on Zembra Island, Tunisia.The objectives of our study were to re-estimate the size of the breeding population on Zembra Island, to reassess the global population size of the species, and to analyse the implications of these findings on status and conservation of this species in the Mediterranean. Using distance sampling, we estimated the Zembra breeding population to be 141,780 pairs (95 % confidence interval 113,720-176,750 pairs).

Biogeosciences and Forestry Biogeosciences and Forestry Should the silviculture of Aleppo pine (Pinus halepensis Mill.) stands in northern Africa be oriented towards wood or seed and cone production? Diagnosis and current potentiality Wahbi Jaouadi (1-2) , Souheila Naghmouchi (3) , Moodi Alsubeie (4) The aim of this work is to review studies on the silviculture of Aleppo pine (Pinus halepensis Mill.) in North Africa and the Mediterranean basin over a period of 50 years. The study presents a synthesis of: (i) silviculture; (ii) wood productivity and growth; (iii) cone and seed production; and (vi) the socioeconomic role of Aleppo pine. The results show that the production of the Aleppo pine is enhanced by the potential of the site, which is closely related to the bioclimatic stage and soil fertility. For instance, production increased from 0.4 to 4 m 3 ha-1 yr-1 in an Aleppo pine stand with a dominant height varying between 9.7 and 22.8 m. Previous studies confirmed that the average maximum volume in annual growth of Aleppo pine is 3.3 m 3 ha-1 yr-1 for 40-year old stands at good-fertility sites. The lowest values (<0.5 m 3 ha-1 yr-1) were recorded for the fourth and last class of productivity in >100-year old stands. There is high demand for Aleppo pine seeds in North Africa, making their production profitable, and this represents an important sector for the sustainable development and improvement of living-standards of the local populations. There has been a steady increase in the demand for seeds across years, with seed production becoming a very promising niche. Silviculture oriented towards the commercial production of seeds is expected to enhance this species, as well as facilitate its preservation.

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Biogeosciences and Forestry Biogeosciences and Forestry Climate change impacts on spatial distribution, tree-ring growth, and water use of stone pine (Pinus pinea L.) forests in the Mediterranean region and silvicultural practices to limit those impacts Kaouther Mechergui (1-2) , Amal Saleh Altamimi (3) , Wahbi Jaouadi (1-2) , Souheila Naghmouchi (2) Stone pine (Pinus pinea L.) has been cultivated since centuries in Mediterranean areas for its products and economic benefits, including edible pine nuts, timber, mushrooms, firewood, and grazing. However, current management objectives of stone pine stands also include recreational use, biodiversity conservation, protection from soil erosion, and CO2 fixation. Stone pine stands are considered to be among the ecosystems most vulnerable to climate change, and the current increase in drought frequency in the Mediterranean Basin has been shown to negatively impact their long-term establishment. Understanding the effects of climate change on the distribution, tree-ring growth and water use of stone pine forests can help assessing the adaptive capacity of the species, and developing management programs aimed at its conservation. This paper reviews the impacts of climate change on stone pine in the Mediterranean region. The high sensitivity of stone pine to climate change has been widely demonstrated in that: (i) climatic models predict the loss of suitable habitats and the shift of its geographical distribution in the next future; (ii) tree-ring analysis showed that winter and spring rainfalls have positive effects on growth, whereas high spring temperature has a negative effect; (iii) the strategy of stone pine to cope with water deficit affects the processes regulating its growth, including wood formation, leading to peculiar tree-ring anatomical features such as intra-annual density fluctuations. The silvicultural interventions and the most effective management strategies for stone pine forests are reviewed and discussed in the context of current climate change in the Mediterranean Basin.

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Eucalyptus is a very important reforestation species in Tunisia, it is from North to South of the country. Micromorphological characters provide basis for classification and delimitation of genus Eucalyptus. Micromorphological features study of seeds of 19 species of eucalyptus reforested in Tunisia facilitated the identification of these species. The hybrid E. gomphocephala x E. cornuta was more tolerant to salt stress and osmotic potential than the others Eucalyptus species studied.