THEANO SAMARA

The purpose of the present research was to study the ability of urban trees’ leaves to retain heavy metals. Three major heavy traffic streets of Thessaloniki were chosen. Two tree species were studied: Ailanthus altissima (Mill.) Swingle and Catalpa bignonioides Walt. and 360 leaf samples were collected from 20 trees. The selection of the species was carried out according to their leaf morphology and silvicultural characteristics. Also, for each tree were measured: breast diameter, tree height, crown height, crown’s diameter and then crown volume was calculated. Two treatments were applied (washed and unwashed leaves). The following heavy metals were measured: iron (Fe), zinc (Zn), manganese (Mn), copper (Cu), cadmium (Cd), cobalt (Co), chromium (Cr), nickel (Ni) and lead (Pb) and the metal concentration was determined with the use of ICP-OES inductively coupled plasma optical emission spectrometry. The concentrations of heavy metals were significantly related to the species for the...

The research investigated forest species selection for urban use concerning their behavior to heavy metals. The research was carried out in trees of three main streets of municipality of Thessalonica: (1) M. Alexandros Avenue, (2) Egnatia road and (3) Karamanlis Avenue. Five forest species were studied: Cupressus arizonica, Albizia julibrissin, Platanus orientalis, Celtis australis and Ligustrum japonicum. Species’ selection (broadleaves or coniferous, deciduous or evergreen) wasmade on the basis of different leaf morphology (lamina-needle, simply-compound, smooth-rough) and their different growth form (tree or shrub). The following silvicultural characteristics were also measured: breast diameter, total height of tree, crown beginning height and crown’s diameters. Heavy metals that were measured are: copper (Cu), lead (Pb), chromium (Cr) nickel (Ni), cadmium (Cd), manganese (Mn) and zinc (Zn). Statistically significant differences between the studied species were found for all meta...

This paper studies the way in which modern land-forest map design contributes to the protection of urban forests generally and the Seich Sou urban forest of Thessaloniki in particular. We also examine the role of cadaster and forest maps in protecting urban forests from abuses such as pressure for housing, which are particularly acute due to their proximity to urban centers. Particular emphasis is given to the Seich Sou urban forest, which provides important protection from erosion and pollution to the city of Thessaloniki. Thessaloniki is characterized by a low proportion of green areas per inhabitant and a high pollution burden. The history of the forest, its ownership status, its legal framework of protection, the problems it faces, as well as the role of the cadaster and forest maps in their resolution are presented. Finally, we conclude by proposing ways of strengthening the protective framework governing Seich Sou, as well as the urban forests of the country in general. The ra...

The main purpose of the study was the absorption of heavy metals in the leaves of forest tree species, which were planted in two different plots for forestry use and environmental restoration. Four species were studied Pinus brutia, Robinia pseudoacaccia, Quercus trojana and Fraxinus ornus. Forty-eight leaf samples were collected which consisted of six samples from each species at each plot. The heavy metal concentrations in the leaves were measured for the following nine heavy metals: iron (Fe), copper (Cu), chromium (Cr), nickel (Ni), cadmium (Cd), manganese (Mn), zinc (Zn), cobalt (Co) and lead (Pd). The determinative estimation of metal concentration was carried out in the clear filtrate, using ICP-OES. Statistically significant differences in the concentrations of the heave metals were found among the species, as well as between the two plots. It was only in Robinia peudoacacia’s leaves that the cadmium concentration showed a statistical difference among the other species. The ...

By using two thinning intensity regimes on a dense 16-year-old black locust (Robinia pseudoacacia L.) stand, two silvopastures were created: a medium density silvopasture (MDS) with 60% mean crown cover and a low density silvopasture (LDS) with 30% mean crown cover. An unthinned section of the stand with 90% mean crown cover was used as control (high density silvopasture: HDS). We measured the diameter at breast height (DBH) and tree height of black locust trees, in all three silvopastures, in 2011 (year of thinning), 2012 and 2013. In addition, we determined the forage production (in 2012 and 2013) and nutritive value (in 2013) of herbaceous vegetation and black locust shoots in the understory. The mean DBH for HDS, MDS and LDS increased from 7.6, 9.5 and 10.9 cm in 2011 to 8.6, 10.7 and 12.1 cm in 2013, respectively. The mean tree height also increased in the same period from 7.9, 9.1 and 9.8 m to 8.9, 10.1 and 10.6 m, for HDS, MDS and LDS, respectively. The mean herbage production was similar (P > 0.05) among silvopastures, although there was a tendency to be higher in the MDS and LDS (1866 and 1957 kg DM/ha, respectively) compared to HDS (1682 kg DM/ha). Additionally, browse from black locust shoots increased forage in MDS and LDS by 751 and 1201 kg DM/ha, respectively. Black locust browse had a higher overall nutritive value than herbage across silvopastures and months. In terms of crude protein, the content in black locust browse was on average twice as high, across sites and years, as that of herbage (239.4 vs. 104.1 g/kg DM; P < 0.05). While neutral detergent fiber and acid detergent fiber content of black locust browse were consistently lower (P < 0.05) than that of herbage, acid detergent lignin content of browse material was higher (P < 0.05) than that of herbage and averaged 94.7 and 75.4 g/kg DM, respectively. Overall, our results show that thinning resulted in higher values for both DBH and height of trees and increased forage in the understory by supplementing herbage with browse of high nutritive value.

The main objective of this research was to study heavy metal absorption by the leaves of main forest species which were planted for that purpose at post-lignite mining landscapes in Northern Greece (Ptolemais, Prefecture of Kozani), as well as in a neighboring region (Kato Grammatiko), 30 km far from the mining area. Four species were studied; two conifers (Pinus nigra Arn., Cupressus arizonica Greene) and two broad-leaved (Robinia pseudoacacia L., Populus nigra L.). The four species varied in their leaf morphology (needles, scale-like leaves, blade, compound or simple, with rough or smooth surfaces). Eighty (80) leaf samples were collected, (10 from each tree species at either site). The heavy metal concentrations measured were iron (Fe), copper (Cu), chromium (Cr), nickel (Ni), cadmium (Cd), manganese (Mn), zinc (Zn) and cobalt (Co). Statistically significant differences (p = 0.01) were found between the lignite deposit and control areas and among the studied species. Higher conce...

The aim of this paper is to select the most suitable tree species in urban areas, taking into consideration their capability of capturing heavy metals. Five of the most common tree species for urban green in Greece were examined with the use of the PROMETHEE method, considering as criteria the captivity of seven heavy metals: manganese, zinc, copper, lead, cadmium, chromium and nickel. The best choice among the alternatives is the Arizona cypress; a reasonable outcome, because as an evergreen species it absorbs heavy metals during the whole year, contrary to deciduous tree species. Broadleaves species with compound leaves could also capture high quantities of heavy metals. The selection of these species would have important benefits for the citizens of Thessaloniki, a city characterised by lack of urban green. Forest policy can play an important role in planning the green spaces in cities in an attempt to increase urban green.

This study was designed to investigate the traffic noise attenuation by vegetation along the ring road of Thessaloniki. Measurements were taken of road traffic noise at two areas, one through a belt of trees and the other above grass-covered ground. 245 measurements were taken in each area during a period of 2 months and expressed as differences in LAeq (equivalent constant Aweighted sound pressure levels). Also there were measurements for the number of vehicles per minute, the type of vehicles and analytic description of vegetation at both areas. The results showed a significant noise reduction through the belt of trees rather than above grass-covered ground. According to the results of this research the largest reduction, 6 dB, was seen in the Pinus brutia belt, 60 m away from the road. This reduction of noise pollution is judged satisfactory because there are belts of trees on both sides of the ring road.

... Ioannis Spanos1,3, Yannis Raftoyannis2, Gerasimos Goudelis2, Eleni Xanthopoulou1, Theano Samara1 & Alexandros Tsiontsis1 1NAGREF, Forest Research Institute, 57006, Vassilika ... their mean height is 12 m, the mean diameter at breast height is 15 cm, the wood volume is ...