A Global Review on Innovative, Sustainable, and Effective Materials Composing Growing Media for Forest Seedling Production

Purpose of Review: The demand for forest tree seedlings is increasing globally, and Sphagnum peat moss is widely used as a component of growing media for container plant production. However, peat extraction is environmentally unsustainable. The forest nursery sector needs to switch to more sustainable alternatives to peat. This review aims to identify potential substitutes for peat by reviewing the worldwide literature on alternative materials for growing media in forest nurseries. Recent Findings: Most studies on alternative growing media focused on single plant species growing under local conditions, thereby limiting generalizations about the effectiveness of alternative materials for plant production. To our knowledge, no systematic reviews of scientific literature on the effectiveness of new, alternative-to-peat materials for enhancing plant growth and the associated growing media characteristics for the forest nursery sector are currently available. Summary: Most of the analyzed case studies focused on angiosperms (73.1%), with the majority of studies coming from tropical seasonal forests/savannas (36.5%), followed by woodlands/shrublands (31.6%), and temperate forests (15.0%) biomes. Compost was the most studied material (19.5%), followed by bark, other organic materials, and manure (9.8, 9.7, and 8.0%, respectively). Green and municipal wastes were the principal sources of compost (> 60%), while agriculture and green wastes were the first sources of other materials (> 90%). Tested materials were dependent on the geographic region. Thus, manure was the most tested material in Africa and South America, tree bark in North America, and compost in Europe, Asia, and Oceania. Alternative materials effectively provided optimal physicochemical characteristics of growing media and enhanced seedling nursery growth when compared with peat-based growing media in more than 60% of the case studies. This review helps to identify research gaps and, most importantly, provides the basis for the future application of alternative growing media materials in forest nursery management worldwide

Structural analysis of mixed stands coming from natural regeneration and plantations after fire

We analyzed the structure and growth of naturally regenerated stands of <i>Pinus brutia</i> that mixed with planted broad-leaved and conifer species, 12 years after wildfire and examined the degree of species mix. Field data on stand structure of <i>P. brutia</i> forest were taken in spring 2009 on northern and southern aspects differing in regeneration conditions. Sixteen sample plots were selected and all individuals and their attributes measured. The results showed that in northern aspects the forest is composed of <i>P. brutia</i> in the over-storey and <i>Quercus pubescens</i> and <i>Cupressus sempervirens</i> in the under-storey, while in southern aspects the forest was mainly composed by <i>P. brutia</i> (81%). Stem diameter distribution of <i>P. brutia</i> in both aspects followed almost a normal pattern. All <i>P. brutia</i> individuals were characterized by vigorous growth and good to normal stem quality. Aspect did not statistically affect structural characteristics of <i>P. brutia</i> trees and saplings. However, on the northern aspect stem diameter, height, crown length and basal area of <i>P. brutia</i> were greater than in the southern aspect. Aspect significantly affected structural characteristics of <i>Q. pubescens</i>

Variation in acorn traits among natural populations of Quercus alnifolia, an endangered species in Cyprus

Quercus alnifolia is an endemic species in Cyprus, and it is rated as Vulnerable (VU) in the Red List of Oaks. Although Q. alnifolia has a great ecological importance, there are only few studies about this species. In this work we have studied the natural variability of this species by analyzing acorn dimensions, acorn mass, length of embryo, moisture content of acorns and seed germinability among the seven acorn provenances, collected in Cyprus. We also determined the seeds responses to drying. Germination trials were also carried out, and differences in seed germination among populations were examined. Rate of water loss and its effect on seed germination was also estimated by application of specific desiccation treatments. The results showed that acorn characteristics significantly differed between the populations, following a general trend to reduce their dimensions and mass with the altitude increase. Seed germination was high for all studied populations, and germination behaviour was similar for all populations. Desiccation of acorns below 35% resulted in a great reduction of seed germination capacity

Seed and cone diversity and seed germination of Pinus pinea in Strofylia Site of the Natura 2000 Network

Variation in cone size, seed number per cone, seed potential, seed efficiency, seed morphology and seed germination behavior of Pinus pinea and its relation to stand conditions was analyzed. Data were collected from P. pinea forest in Strofylia, southern Greece, a forest that belongs to the Natura 2000 European network and the RAMSAR convention and is characterized by the absence of regeneration for many decades. The pine stands found in the area were distinguished into five categories according to a previous study and our observations, regarding stand age, canopy cover and the degree of stress by human pressure. The categories are: (I) young artificial, (II) closed-mature, (III) open-mature, (IV) over-mature stands and (V) highly degraded stands. Cones were collected from all stand types and their morphological characteristics as well as their seed production were measured. Seeds were extracted from the collected cones, measured and their germination behavior was tested. The findings showed that the over-mature and the high degraded stands and to a lesser extent, the closed-mature stands, produced significantly smaller cones with a lower seed potential, a lower number of filled seeds per cone, a greater number of not fully developed seeds and reduced seed morphological characteristics than the young and open-mature stands. However, the seed germination behavior of fully developed seeds was only slightly affected by the stand type. © 2008 Springer Science+Business Media B.V

Bilateral claw hand: An uncommon presentation of regional Guillain-Barré syndrome

We present an uncommon case of a 38-year-old man presented with bilateral subacute weakness of intrinsic hand muscles, manifesting as bilateral claw-hand, without sensory deficits and absent tendon reflexes in upper arms. Nerve conduction studies showed findings consistent with demyelinating GBS. During the fourth day of hospitalization the patient presented symmetrical distal leg weakness and was treated with intravenous immunoglobulin. © 2013 Elsevier B.V

A Sustainable Strategy for Reforestation and Restoration of Burnt Natural Areas in Mediterranean Regions: A Case Study from Greece

Greece, along with most of the countries in the Mediterranean basin, is historically linked with forest fires. Wildfires have always occurred, are happening, and will continue to occur, causing serious problems regarding the sustainability of natural resources. Their frequency, however, has shown a noticeable increase during the last decades; according to the most recent projections, the broader Mediterranean region will face significant challenges in the future within the context of climate change. Despite the historical experience of forest fires in Greece, a standardized and up-to-date system for identifying and prioritizing burnt areas, in relation to their restoration needs, has not yet been developed and adopted. In this paper, a systematic methodological approach for decision-making regarding the identification and prioritization of active restoration/reforestation of burnt areas is proposed. This approach is based on critical parameters, such as the regeneration potential of the affected forest species, the “fire history”, and the slope of the affected areas. The proposed methodological approach can be applied in all burnt natural areas in the country in the future, as well as in other areas of the Mediterranean region. The fire impact on Natura 2000 sites is also assessed to highlight the importance of restoration and conservation needs in protected areas. The results from case studies are presented, and future steps and policy recommendations for the post-fire management of natural ecosystems are discussed to enable the sustainable management of forest resources in the burnt areas