Marginal/peripheral populations of forest tree species and their conservation status: report for Mediterranean region

The Mediterranean region includes 13 countries among Europe, Near Orient, and Africa. This area is a huge “hot spot” of  cultures, religions, socio-economical situations, and of habitats and  biodiversity. The report illustrates the geographical and ecological features of the region. Forest ecosystems and vegetation traits, with particular focus on forest species growing at the edge of their distribution range, are here compiled. The accuracy of reports, shows the interest and attention that the Mediterranean countries have for the different and complex situations of marginality that characterizes the presence of many forest species in this region. In this area the occurrence of 166  marginal and peripheral (MaP) populations of different species has been detected. Most of populations are characterised by vulnerability and fragility. Many MaP survive in environmental refugia and /or in isolated stands. However, most of the MaP populations identified by FP1202 experts are located in protected areas and also sometimes registered as seed sources, although Mediterranean region appears heterogeneous with respect to protection measures

Re-use of wastewater for a sustainable forest production and climate change mitigation under arid environments

Over the last decades biotic and abiotic constrains together with human actions are determining a substantial environmental pressure, particularly in dry lands as the south of the Mediterranean region. From very long time, indeed, simultaneous drivers such as demographic growth, climate change and socio-economic factors are weakening the previous homeostasis between human needs and natural resources on the regional scale.Resulting pressures are determining environmental degradation and increase of desertification risk for the arid and semiarid lands. Water quality and availability are both crucial points limiting people well-being and livelihoods in the same context. Scarcity of fresh water and heavy and mismanaged production of wastewater are the main factors affecting water resources. Increasing pollution of soil and ground waters reduces the possibility of sustainable development of local communities with relevant social consequences. The FAO's supporting program in north Africa aims to: a) develop new and cheaper phytotechnologies (e.g. constructed wetland system; innovative treatment system for reuse of waste water for fertigation); b) treat wastewater for water quality protection; c) promote land recovery by means of sustainable multipurpose forestry; d) adopt bioengineering interventions to stop slopes erosion and protect urban, and semi-urban infrastructures; e) create pilot demonstrative areas to test multi-purpose sustainable agroforestry systems. Within this frame, an integrated approach was designed to promote innovative sustainable water management and multipurpose forestry, in order to mitigate the effects of climate change, promote land recovery, and improve the livelihoods of local population. The present paper aims to provide an overview of the FAO project GCP/RAB/013/ITA. Particularly, two pilot studies are shown and discussed

Identification of cork characters for phenotypic selection

Global change effects can determine major changes in species distribution and productivity. In the Mediterranean region of the severity of hot and dry periods is growing and an increased frequency of extreme events and a major vulnerability of natural ecosystems is evident. Cork oak (Quercus suber L.) is widely spread in the West Mediterranean region and its economic and social is important

Priorities, challenges and opportunities for supplying tree genetic resources

Special issue on Landscape restoratio

Ecology, growth and management of black locust (Robinia pseudoacacia L.), a non‑native species integrated into European forests

Black locust (Robinia pseudoacacia L.), a species native to the eastern North America, was introduced to Europe probably in 1601 and currently extends over 2.3 × 106 ha. It has become naturalized in all sub-Mediterranean and temperate regions rivaling Populus spp. as the second most planted broadleaved tree species worldwide after Eucalyptus spp. This wide-spreading planting is because black locust is an important multipurpose species, producing wood, fodder, and a source of honey as well as bio-oil and biomass. It is also important for carbon sequestration, soil stabilization and re-vegetation of landfills, mining areas and wastelands, in biotherapy and landscaping. In Europe, black locust is drought tolerant so grows in areas with annual precipitation as low as 500–550 mm. It tolerates dry, nutrient poor soils but grows best on deep, nutrient-rich, well-drained soils. It is a fast-growing tree and the height, diameter and volume growth peak before the age of 20. It mostly regenerates vegetatively by root suckers under a simple coppice system, which is considered the most cost-effective management system. It also regenerates, but less frequently, by stool sprouts. Its early silviculture in production forests includes release cutting to promote root suckers rather than stool shoots, and cleaning-respacing to remove low-quality stems, reduce the number of shoots per stool, and adjust spacing between root suckers. In addition, early, moderate and frequent thinning as well as limited pruning are carried out focusing on crop trees. The species is regarded as invasive in several European countries and its range here is expected to expand under predicted climate changes

Acute Delta Hepatitis in Italy spanning three decades (1991–2019): Evidence for the effectiveness of the hepatitis B vaccination campaign

Updated incidence data of acute Delta virus hepatitis (HDV) are lacking worldwide. Our aim was to evaluate incidence of and risk factors for acute HDV in Italy after the introduction of the compulsory vaccination against hepatitis B virus (HBV) in 1991. Data were obtained from the National Surveillance System of acute viral hepatitis (SEIEVA). Independent predictors of HDV were assessed by logistic-regression analysis. The incidence of acute HDV per 1-million population declined from 3.2 cases in 1987 to 0.04 in 2019, parallel to that of acute HBV per 100,000 from 10.0 to 0.39 cases during the same period. The median age of cases increased from 27 years in the decade 1991-1999 to 44 years in the decade 2010-2019 (p < .001). Over the same period, the male/female ratio decreased from 3.8 to 2.1, the proportion of coinfections increased from 55% to 75% (p = .003) and that of HBsAg positive acute hepatitis tested for by IgM anti-HDV linearly decreased from 50.1% to 34.1% (p < .001). People born abroad accounted for 24.6% of cases in 2004-2010 and 32.1% in 2011-2019. In the period 2010-2019, risky sexual behaviour (O.R. 4.2; 95%CI: 1.4-12.8) was the sole independent predictor of acute HDV; conversely intravenous drug use was no longer associated (O.R. 1.25; 95%CI: 0.15-10.22) with this. In conclusion, HBV vaccination was an effective measure to control acute HDV. Intravenous drug use is no longer an efficient mode of HDV spread. Testing for IgM-anti HDV is a grey area requiring alert. Acute HDV in foreigners should be monitored in the years to come

Photosynthetic Diffusional Constraints Affect Yield in Drought Stressed Rice Cultivars during Flowering

<div><p>Global production of rice (<i>Oryza sativa</i>) grain is limited by water availability and the low ‘leaf-level’ photosynthetic capacity of many cultivars. <i>Oryza sativa</i> is extremely susceptible to water-deficits; therefore, predicted increases in the frequency and duration of drought events, combined with future rises in global temperatures and food demand, necessitate the development of more productive and drought tolerant cultivars. We investigated the underlying physiological, isotopic and morphological responses to water-deficit in seven common varieties of <i>O. sativa</i>, subjected to prolonged drought of varying intensities, for phenotyping purposes in open field conditions. Significant variation was observed in leaf-level photosynthesis rates (<i>A</i>) under both water treatments. Yield and <i>A</i> were influenced by the conductance of the mesophyll layer to CO₂ (<i>g</i>_m) and not by stomatal conductance (<i>g</i>_s). Mesophyll conductance declined during drought to differing extents among the cultivars; those varieties that maintained <i>g</i>_m during water-deficit sustained <i>A</i> and yield to a greater extent. However, the variety with the highest <i>g</i>_m and yield under well-watered conditions (IR55419-04) was distinct from the most effective cultivar under drought (Vandana). Mesophyll conductance most effectively characterises the photosynthetic capacity and yield of <i>O. sativa</i> cultivars under both well-watered and water-deficit conditions; however, the desired attributes of high <i>g</i>_m during optimal growth conditions and the capacity for <i>g</i>_m to remain constant during water-deficit may be mutually exclusive. Nonetheless, future genetic and physiological studies aimed at enhancing <i>O. sativa</i> yield and drought stress tolerance should investigate the biochemistry and morphology of the interface between the sub-stomatal pore and mesophyll layer.</p></div

Measurements of (a) photosynthesis rate (<i>A</i>), (b) stomatal conductance (<i>g</i>_s), (c) mesophyll conductance (<i>g</i>_m), and (d) intrinsic transpiration efficiency (<i>A</i>/<i>g</i>_s) in control and water-stressed leaves of the seven <i>Oryza sativa</i> genotypes.

<p>The measurements were made on the flag leaf in saturating PPFD (1400 µmol m⁻²s⁻¹), with relative humidity ranging between 45–55%, and a leaf temperature of 30°C. Data are means of 4 to 7 plants per treatment. Error bars as in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0109054#pone-0109054-g001" target="_blank">Figure 1</a>. Different letters denote significant differences among means derived using a factorial ANOVA and Tukey <i>post-hoc</i> test.</p