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This work illustrates the use and some related results of Artificial Neural Networks (ANNs) for data
quality control of environmental time series and for reconstruction of missing data. ANNs are applied
to the following problems: i) short and medium-term predicting of air pollutant concentrations in urban
areas, ii) interpolating and extrapolating daily maximum temperature, iii) replacing time distribution
with spatial distributed information (pollutant concentrations at different measuring sites). Observed
versus predicted data are compared to test the efficacy of ANNs in simulating environmental processes.
Results confirm ANNs as an improvement of classical models and show the utility of ANNs for
restoration of time series..

The present work argues that sustainable tourism is essential to the long-term survival of the tourism
industry in Europe. Sustainable tourism may be regarded as a means of redressing economic imbalances
between European regions and nations without producing adverse environmental, social and cultural
effects on host communities. Conflicts between the development of a local economy and the interests
of ‘outside’ investors from elsewhere among EU member nations must be resolved in the best
interests of the local people and the environment. The degree to which profits are expropriated from a
local area or region is a particular concern. The transnational character of tourism businesses makes
necessary a European-wide policy, where the quality of life and nature’s conservation will obtain a premortial
place.

Fly ash (FA) and fluidized bed ash (FBA) solutions were evaluated as amendments for acid-disturbed
lands, more specifically for treating acidic and metal contaminated soil. While titrating the ash materials
with different volumes of acid, pH changes were monitored as a function of time and the acid volume
added. The release of metals from the ash materials as a function of pH was also monitored. An
acid mine drainage (AMD) solution was equilibrated with ash materials and clay and the metal removal
from the solutions evaluated. Both FA and FBA produced solutions of high initial pH. However, FBA
indicated a higher buffering capacity resulting in a steeper titration curve. The system pH strongly
impacted metal release from the ash materials. The leaching experiment indicated a pattern whereby
the basic metals (Ca and Na) were released at higher pH and the acidic metals (Fe and Cr) at lower
pH. Limestone had almost double the buffer intensity but a lower initial pH than ash materials.
Comparison of ash materials with two types of clay revealed that ash materials were better alternatives
for treating acidic and high metal content wastes. Albeit both ash materials were able to treat AMD,
their overdose could lead to trace metal accumulation with negative consequences to the environment.

In the Mediterranean region, fire is a natural factor, which contributes in the shaping of landscape and
the preservation of a high degree of biodiversity. However, often repeated burning has negative impacts
on the forested landscapes. When the processes of natural or artificial regeneration are efficient and
the fire frequency is sufficiently low to enable the recovery of vegetation, recovery time T can be used
as a tool for setting priorities for the preservation of ecological and social functions of the forested
landsapes. Using a simple linear approach, we argue that their situation can be considered as acceptable,
when the percentage of the yearly burned area in relation to the total forested area is much lower
than 100/T (for practical purposes just lower than 10/T). This empirical rule was applied to the Greek
forested landscapes. In the case of pine forests of Pinus halepensis and Pinus brutia, it was found that
the condition implied by the rule was not satisfied and, therefore, a reduction of the yearly burned areas
of these lowland conifer forests is necessary. However, as far as the other types of forests, as well as
macchia and phrygana are concerned, the condition is satisfied.