On the floristic diversity of sacred forests in north Pindοs
Sacred forests are places with special significance for the conservation of biodiversity. In north Pindus (NW Greece) a network of several sacred natural sites has been located. In order to study the floristic diversity of sacred forests eight of them were selected in Zagori and Konitsa area. Additionally, eight similar but conventional managed forest sites were selected close to the sacred in order to serve as control for comparison. The flora of the sacred and the control was recorded using 32 Braun-Blanquet quadrats in total. For the comparison of the plant communities, species richness, Shannon – Wiener (H) adiversity index and similarity indices Sorensen (Ss) and Jaccard (Sj) were calculated. Floristic diversity and species richness depend on parameters other than age and stand structure. Grazing impact seems important, whereas a diversity pattern related to sacred and managed forests in the study area is missing.
Sheep and goat summer grazing impact on plant species composition and diversity of an open Kermes oak shrubland
Shrublands occupy an area of 3,1 million hectares in Greece and contribute substantially to feeding of grazing animals. One of the economically important evergreen shrublands is that of kermes oak (Quercus coccifera L). Kermes oak shrublands provide green and of relatively high quality foliage to grazing animals almost all year-round. They are mainly grazed by goats and secondly by sheep. The objective of the study was to evaluate the impact of 1) goat, 2) sheep and 3) mixed moderate summer grazing on species composition and plant diversity of an open kermes oak shrubland. The research was conducted in Chrysopigi, Serres, north Greece, at 650m altitude and a subhumid climate. The experimental area of 21 ha open kermes oak shrubland was divided into six 3,5 ha each, equal size plots. A completely randomized design was applied for the three treatments: 1) goat grazing, 2) sheep grazing and 3) mixed sheep and goat grazing. All treatments were repeated twice. Vegetation parameters were measured at the end of May for three consecutive years (1997, 1998 and 1999). Measurements of 1997 were considered as reference data. The number of grazing animals was equal to grazing capacity of every plot. Plant species composition was measured using the line point method. Species richness and species abundance were measured in 0,5x 0,5 m quadrates. Then, plant diversity was calculated using the Shannon-Wiener (H) diversity index. Species composition for all grazing treatments varied through the years according to precipitation’s fluctuation and to grazing treatment. Plant diversity increased but not significantly, by 33,8% for goats, 5,4% for sheep and 15,4% for the mixed treatment through the years (1997-1999).
Medicinal plant species of the rangeland ecosystems in Greece
The rangeland ecosystems of Greece are constituted by a large number of plant species. Many of these plant species have medicinal properties. These medicinal plant species have been used since antiquity in order to cover medicinal needs. Moreover, some of these plant species cover the same needs up until now. The science development permitted the analysis and determination of the medicinal plant species compounds, on which their medicinal activity is due to. The basis for drugs production, herbal or non herbal was based on this knowledge. The objective of this study was the investigation and the report of the medicinal uses of plant species that are dominant in rangeland ecosystems of Greece. The 54,4% of the recorded taxa in rangeland ecosystems of lower altitudes in Greece and the 45,5% of the taxa in higher elevations, are considered to have medicinal properties. The main medicinal properties are mainly for the respiratory systems, the diuretic and tonotic use at 22,4%, 20,6% and 15,5%, respectively. The sustainable management of the rangeland ecosystems should take into consideration the presence of the pharmaceutical plants in the ecosystems and take initiative for their conservation.
Investigation of Lotus corniculatus L. adaptation under limited irrigation
The purpose of this study was to investigate the adaptation of a population of Lotus corniculatus in conditions of limited irrigation. Plants from a natural population were harvested and transplanted into plastic pots. After a period of plant adjustment two irrigation treatments were applied: a) irrigation to the point of field capacity and b) limited irrigation. During the growing period of 2013, the water potential (Ψ), osmotic potential (Ψs) and stomatal conductance (gs) were measured under field conditions, while the turgor potential (Ψρ) and the relative water content (RWC) were calculated. It was found that for the same Ψ, plants under limited irrigation showed higher water deficit and stomatal conductance and positive turgor, which remained almost constant throughout the growing season. The maintenance of turgor under water stress could be due to the fact that the reduction of Ψs was proportional to the reduction of Ψ. The above results suggest that L. corniculatus shows plasticity and is able to grow under limited irrigation, while maintaining high relative turgor potential and relative water content.
Climatic changes and grasslands
Aim of the present study was to investigate the main parameters of climatic change (temperature, precipitation, CO2 concentration) and their effects on grassland ecosystems, with special reference to plant distribution, biodiversity and productivity. The various climatic change scenarios predict an increase in temperature and a decrease in annual rainfall, and therefore, a decrease in plant production, especially for the countries of the Mediterranean zone. In addition, climatic changes are predicted to alter the C3/C4 species ratio, and the forage quality, through changes in the C/N ratio. Another important change will be the phenomenon of plant invasion of mainly grass species in places outside their natural distribution, strongly affecting the indigenous species. The biotic changes caused by the invasion species could increase the ecosystem’s susceptibility and therefore the risk for new species invasions.
