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In an experimental beech ( L.) coppice plot, throughfall, stemflow and superficial runoff were monitored on a single event basis, in order to verify the short term hydrological balance in different conditions of leaf cover. Rainfall events were simulated using a rainfall simulator, operated at two different intensities. The plot was hydraulically isolated, along its whole perimeter and a small drain, placed in the lowest part of the plot, was used to collect the superficial runoff. Twelve rain gauges were used to survey the throughfall whereas the stemflow was collected through rubber collars. Superficial flows were measured both by sampling the discharges coming out of the plot and by collecting the total water runoff volumes.

Rainfall simulators have been developed as tools for evaluating hydrological and erosive processes due to agronomical activities and have been very rarely used in forested areas. When a rainfall simulator is operating under forest cover, the characteristics of this peculiar environment (high trees, irregular topography, steep slopes, difficulties in supplying water) as well as the gross-rainfall transformation and redistribution on soil surface (as rain is filtered through the canopy) have to be taken into account.

In a Mill. forest of central Greece, we studied the effects of two fires on postfire plant community recovery by comparing a site that was burned once and another adjacent that was burned twice. During the first 15 months after fire, we monitored plant species recruitment, plant density and growth. Lower species richness and plant densitywere observed in the site burned twice compared to that burned only once. The growth ofwoody species did not differ between the two treatments and presented high variability even within the same plot. Resprouting plant species appeared earlier than obligatory seeders. Fifteen months after fire, the ecosystem was dominated by the maquis species that existed in the prefire period, mainly L., L., L., with a low contribution of Pinus halepensis seedlings and a greater proportion of species ( L., L., L.).

After a wildfire in a Mill. forest, in northern Greece, the burned trees were logged and the logs were removed either by mechanical or animal traction. The effects of logging and log removal methods on soil and vegetation recovery were evaluated comparing the logged sites with a burned but unlogged site and the unburned forest. Fire and logging did not affect the soil pH and caused only a short-term reduction in organic matter content. Two years after the fire, the highest rates of soil loss were observed in the logged area where mules were used for log removal. Soil moisture showed some differences between treatments during the first year after fire but then values were similar. Logging and particularly the use of skidders for log removal caused an initial increase in the amount of exposed bare ground but later when vegetation cover increased differences were minimized. The main woody species showed a species specific response to the treatments and while seeder species were favoured in the unlogged sites the same was not true for the respouters. In general, the growth and survival of pine seedlings was not affected by treatments.

During 1997 a fire destroyed about 62% of the urban forest in the city of Thessaloniki, northern Greece. Between 50 and 80% of the forest vegetation was burned within the watersheds of the six torrents that flowed across the destroyed area. In this area the forest service constructed agrotechnical, and flood-protection works in the streams and the basins of the torrents to prevent erosion and to protect the city from flooding. The agrotechnical works consisted of channelling, drifts of branches and log erosion barriers. In the present study the effectiveness of the operation of the agrotechnical works in the protection of the erosion phenomena is examined. The success of the agrotechnical works are examined 7 years after their construction and the contribution of these works to the natural regeneration of the forest is evaluated. The erosion prevention and flood protection measures that were constructed contribute significantly to the stability of the forestal soil and the protection of floods. Their contributions in assisting the natural reforestation works were also remarkable.

The increased number of catastrophic slope instabilities in Europe in the last decade highlights the need for integrated management of such occurrences. The decision support system presented here incorporates expert knowledge on slope stability and eco-engineering and represents user-friendly solution for help in decision making process on mitigation of slope instability. Based on the results of field studies, experience of the project partners, theory and case studies available in the literature, the slope decision system (SDSS) is a modern decision support system that promotes use of eco-engineering solutions for mitigation of slope stability problems connected with the uppermost soil horizons. The basic considerations, design aims and objectives, together with the advantages and the disadvantages of the approach are discussed in the light of ever-evolving decision making system theory. The future of eco-engineering decision support systems is also discussed with a special emphasis on the learning component for the end-user.

A decision support system (DSS) has been developed to assist expert and non-expert users in the evaluation and selection of eco-engineering strategies for slope protection. This DSS combines a qualitative hazard assessment of erosion and mass movements with a detailed catalogue of eco-engineering strategies for slope protection of which the suitability is evaluated in relation to the data entered. The slope decision support system is a knowledgebased DSS in which knowledge is stored in frames containing rules that can evaluate the available information for a project, stored as project specific information in a data file. The advantages of such a system are that it accepts incomplete information and that the qualitative nature of the information does not instil the user with a sense of unjustified exactitude. By its multidisciplinary and progressive nature, the DSS will be of value during the initial stages of an eco-engineering project when data collection and the potential of difierent eco-engineering strategies are considered. The accent of the output of the DSS is on the application of eco-engineering strategies for slope protection as an environmentally friendly solution aiding sustainable development. For its acceptance within the engineering community, the DSS needs to prove its predictive capacity. Therefore, its performance has been benchmarked against successful and unsuccessful cases of slope stabilisation using eco-engineering. The target audience and the areas of application of this DSS are reviewed and the strategies for further development in this area suggested.

A number of landscape projects have been completed around Athens (Greece) for the 2004 Olympic Games. The common purpose of these projects was the promotion of quality in: design, construction and maintenance stages. They also comply with environmental management, which is a method of organising and implementing environmental protection measures.

The ability of different types of plants to become established was studied on the road sides of the Egnatia highway, Thessaloniki, Greece.Amixture of perennial plants (grasses, legumes and forbs)was sownat equal quantities without any preparation of the sowed soil surface. Plant density (individuals/m), above and underground dry weight per individual plant (grams/plant), were measured during the growing season. The results showed that drought tolerant species of all plant life forms had high survival percentages and contributed significantly to the vegetation cover at the end of the growing season. Drought tolerance and the existence of rhizomes benefited the establishment ability of grass species. The best adapted species were the grasses L., Leyss., L. and Schleich, the legume L. and the forb Scop.

The Egnatia Motorway is the greatest highway infrastructure project currently being constructed in Southern Europe. The construction of such a large-scale project is expected to cause an environmental and hence landscape disturbance. Landscapingworks are, therefore, of a critical importance and are imposed by the Environmental Terms approved for each project. As far as erosion is concerned, the hydroseeding of herbaceous species is a widely used practice for the protection of slopes against surface erosion, which is preferably applied immediately after their final configuration. Undoubtedly, the establishment of woody species immediately after the configuration of the surfaces under restoration (cuts and fills) and at the minimum possible cost constitutes one of the most preferable landscaping solutions in highway construction. In this context, the Green Unit of “Egnatia Odos A.E.” carried out an experimental application of woody species hydroseeding, with the purpose of investigating the effectiveness of this method, as far as the establishment of woody vegetation on the Egnatia Motorway slopes in concerned. This application was implemented in two stages. The first one was carried out in cooperation with a group of experts from the Aristotle University of Thessaloniki, at a small scale and after strict experimental planning. The second one was an experimental–pilot application, in order to re-check the positive results of the previous test, to extract more useful conclusions and to check this method in terms of its feasibility as part of the green works performed along the Egnatia Motorway. Another issue, which is closely related to the previous one, is the protection of slopes against erosion by application of various engineering methods using cuttings, apart from hydroseeding and planting. These works, which are compliant with the general environment-friendly philosophy in approaching such issues, are supplementary to the hydroseeding of herbaceous species and are more effective in anti-erosion action when compared to conventional planting works. At the same time, this method serves the need for aesthetic restoration.