Aristotelis C. Papageorgiou

Genetic variation of beech (Fagus sylvatica L.) in Rodopi (N.E. Greece)

The recent taxonomic classification of beech in Europe considers existence of one species (Fagus sylvatica L.) with two subspecies: F. sylvatica ssp. sylvatica and F. sylvatica ssp. orientalis. Four beech populations growing on the Greek part of the Rodopi Mountains were studied using morphological traits as well as DNA molecular markers (AFLPs and chloroplast DNA SSR). The aim of the study was to describe the variation patterns of beech in the Rodopi Mountains and to test the hypothesis of possible introgression between the beech subspecies’ sylvatica and orientalis in this area. Both morphological traits and gene markers revealed a possible influence of F. orientalis on the east side of Rodopi and at the low elevations, while characters resembling F. sylvatica were observed mainly on the western part of the mountains and in higher altitudes. There was a clinal increase of genetic diversity from the west to the east, reaching a level firstly reported for beech populations. These results can be explained either by the existence of a main refugial area for beech during the last glaciation or by the occurrence of a recent hybridization among the subspecies, which were spatially isolated during the last glaciation and came into reproductive contact during their postglacial remigration. These two scenarios are not necessarily mutually exclusive.

Modelling site quality and individual-tree growth in pure and mixed Pinus brutia stands in north-east Greece

Abstract• Simulation tools, based on individual tree growth and mortality models can produce the most detailed predictions of forest stand development under different management schedules. These models allow the manager to predict the development of any type of stand (even- and uneven-aged, and pure and mixed stands).• Different model approaches and predictors are required for pure even-aged or mixed uneven-aged forest stands. This study developed and compared two sets of models which enable tree-level simulation of the development of pure and mixed stands of Pinus brutia in north-east Greece. The first set of models for even-aged forestry consists of site index models, diameter growth models, tree height models, and mortality models. The second set, which is for uneven-aged forestry, uses a past growth index instead of a site index.• The simulations and overall fitting statistics suggest that the two types of models provide realistic and accurate predictions of forest stand development and allow one to simulate the development of complex Pinus brutia stand structures in Dadia National Park forests.• The advantages of the two approaches are discussed and it is suggested that the growth index is an effective predictor of site quality and the set of models which used such variable as predictor performed in a similar way as the models using site index, which require more information and a given stand structure (even-aged).Résumé• Des outils de simulation basés sur la croissance individuelle des arbres et des modèles de mortalité peuvent produire les prédictions les plus détaillées sur le développement des peuplements forestiers sous différents programmes de gestion. Ces modèles permettent au gestionnaire de prédire le développement de n’importe quel type de peuplement (équienne et inéquienne, peuplement pur et peuplement mélangé).• Différents modèles d’approche et des indices sont requis pour les peuplements purs équiennes ou les peuplements mélangés inéquiennes. Cette étude a développé et comparé deux séries de modèles qui permettent la simulation, au niveau de l’arbre, du développement des peuplements purs et mélangés de Pinus brutia dans le nord-est de la Grèce. La première série de modèles pour la sylviculture équienne consiste en modèles de site index, modèles de croissance en diamètre, modèles de croissance en hauteur et modèles de mortalité. La seconde série destinée à une sylviculture inéquienne, utilise un index de croissance passée au lieu d’un site index.• Les simulations et des statistiques d’ajustement d’ensemble suggèrent que les deux types de modèles fournissent des prédictions réalistes et précises du développement des peuplements forestiers et permettent de simuler le développement des structures complexes des peuplements de Pinus brutia du Parc National de Dadia.• Les avantages des deux approches sont discutés et il est suggéré que l’index de croissance est un indice de la qualité de la station et la série de modèles qui utilise ce genre de variables comme indice opère d’une manière similaire à celle des modèles utilisant les site index, qui demandent plus d’information et une structure donnée de peuplement (équienne).

High chloroplast haplotype diversity in Greek populations of beech (Fagus sylvatica L.).

The distribution of chloroplast DNA (cpDNA) variations in Greek beech (Fagus sylvatica L.) populations was studied using chloroplast microsatellite markers. Thirteen haplotypes were identified from 40 populations by combining three different primers. Most of the cpDNA variation was distributed among populations, but a considerable variation was also observed within populations. The total diversity was very high for all regions. The N(st)/G(st) comparison was significant, indicating phylogenetic subdivision, but no strong spatial structure was detected, suggesting complex post-glacial migration patterns. Possible scenarios explaining this diversity pattern include the existence of several separated refugia in the region, the recolonisation of mountains by different beech lineages and the formation of an introgression zone between two different beech subspecies in the eastern part of the country.

Conservation of Biodiversity in Managed Forests: Developing an Adaptive Decision Support System

Forest ecosystems provide several goods and services, but strategies for the conservation of biodiversity are missing in traditional forest management schemes. In this paper we develope a decision support system to optimize the conservation of biodiversity in managed forests, taking Dadia National Park as a case study area, a local Mediterranean hotspot of biodiversity in northeastern Greece. Using environmental niche factor analysis, we produced a series of spatially explicit habitat suitability models for vascular plants, amphibians, small birds and raptors and an overall model for total biodiversity. Further, we produced maps related to timber production and investigated potential conflicts between conservation of biodiversity and wood production. A decision support system based on a conflict assessment was created using three management scenarios. It enables the establishment of integrated management strategies and the assessment of their effects on biodiversity and timber production. Habitat suitability models for selected groups of organisms were found very effective to investigate the impact of the management on forests and wildlife. Further evaluation of key indicator taxa on these models could improve decision support systems and the sustainable management of forests.

Genetic differences between autochthonous and breeding populations of common cypress (Cupressus sempervirens L.) in Greece

Individuals were selected for resistance against the imperfect fungus Seiridium cardinale Wag in six common cypress populations (Cupressus sempervirens L.) in Greece. A total of 109 resistant clones and 140 trees from their base populations were surveyed at several allozyme loci. The comparison yielded information on changes in genetic variation due to artificial selection. The genetic structure of the breeding populations was similar to their base populations. Nevertheless, the number of rare alleles among the resistant clones had decreased, showing a similar trend at most loci and for most comparisons. Possible implications for breeding strategies are discussed.

Landscape Approaches and GIS for Biodiversity Management

Remote sensing now routinely provides environmental information ranging from global to local scales, and geographical information systems provide, among other applications, necessary interfaces to store, analyse and visualise spatial data; increased computational capacities triggered even more such applications. In this chapter, we demonstrate how the combination of landscape approaches, remote sensing and GIS aids conservation and management of biodiversity. We therefore summarise six case studies from Dadia National Park (Dadia NP), in northeastern Greece. The studies aimed at (1) modelling of nesting habitat for a flagship species, (2) evaluation of land-use change, (3) detecting statistical dimensions and spatial patterns of landscape structure, (4) testing the performance of landscape metrics as indicators of biodiversity, (5) developing a GIS approach for a systematic raptor monitoring, and (6) developing a decision-support system to optimise conservation of biodiversity in managed forests.

The relationship between vegetation and modern pollen assemblages on Mount Paggeo (NE Greece)

In this study, we investigated the relationship between vegetation and modern-pollen rain along the elevational gradient of Mount Paggeo. We apply multivariate data analysis to assess the relationship between vegetation and modern-pollen rain and quantify the representativeness of forest zones. This study represents the first statistical analysis of pollen-vegetation relationship along an elevational gradient in Greece. Hence, this paper improves confidence in interpretation of palynological records from north-eastern Greece and may refine past climate reconstructions for a more accurate comparison of data and modelling. Numerical classification and ordination were performed on pollen data to assess differences among plant communities that beech ( Fagus sylvatica ) dominates or co-dominates. The results show a strong relationship between altitude, arboreal cover, human impact and variations in pollen and nonpollen palynomorph taxa percentages.

Distribution and physical traits of red wood ant mounds in a managed Rhodope mountains forest

Red wood ants (RWA) are of great ecological importance for the forest ecosystem. Forestry practices, like clear-cutting, and trampling load, due to tourism, logging, and grazing stock, can greatly affect their colonies, disturbing their microhabitat. RWA in Greek forests have not been investigated so far. We herein report on the distribution and morphological traits of Formica lugubris mounds studied in Elatia forest (Rhodope mountains, Northern Greece), an all-aged managed mixed forest where selective logging practices are performed. Nearby vegetation, slope, canopy cover, shrub density, and distance from the nearest neighboring trees were also recorded. Mound density was shown to be much higher in this Greek forest compared to RWA mounds in other European-managed forests. Furthermore, we recorded a continuous nest establishment, despite forest management disturbances and trampling load. Our study suggests that single-tree selective forestry practices are essential for creating ideal microhabitats for the RWA and, therefore, for maintaining RWA populations.