Irrigation and Drainage Scheme of the Plain of Arta – Effects on the Rural Landscape and the Wetlands of Amvrakikos’ Natura Area

AbstractAmvrakikos Wetlands National Park is located in the North-West Greece. It is an area of high environmental importance, as it is characterized by a very rich biodiversity. Because of it's importance, the north part of the gulf is protected by Ramsar Convention and is part of the EU NATURA network. The adjacent plain of Arta (most of which is part of the land part of the park), hosts intensively cultivated, irrigated agricultural land and a number of food processing facilities and though it constitutes a major threat for this ecosystem.As water is plentiful and cheap, most farmers over-irrigate using water by the old open canal scheme that covers part of the plain and from numerous drillings most of which are illegal. The main pathways of agricultural pollutants (fertilizers, pesticides etc) are three rivers (Louros, Aracthos and Vovos) and three main draining canals (Salaoras, Fidokastrou and Neochoriou). This presentation, reviews information from several research works of the last 10 years which investigated the effects of agricultural activity to the coastal and the inland natural and rural landscape. Efforts that have been made (installation of measuring - alarming stations, educational sessions for farmers, de-nitrification programs etc) during the same period are also referred

Effects of planting and structural configurations on human thermal comfort in a schoolyard

Schoolyards are places where children spend a lot of their day. In highly populated Greek cities, schoolyards are usually surrounded by dense and elevated buildings, while the grounds are largely hard surfaces comprising asphalt, concrete, bricks and stone paving. This combination creates considerable thermal discomfort, especially in hot or Mediterranean-type climates. A study exploring the redesign of schoolyards to improve thermal comfort and heat stress conditions is presented in this paper. This included use of a microclimate model ENVI-met (V4), first validated using experimental data and then later applied to different case studies in schoolyards of Volos, a coastal city in central Greece. Microclimate measurements were carried out and thermal comfort and heat stress conditions evaluated by means of the physiologically equivalent temperature (PET, °C). The impact of materials, structures, obstacles, and different tree species on thermal comfort was also assessed. The results of the measured and simulated values were similar, including air temperature, relative humidity, solar radiation and mean radiant temperature (Tmrt). ENVI-met was then used to evaluate different landscape design proposals to improve outdoor human thermal comfort that prevail in schoolyards. © 2017 ISHS

Sustainable water management in green roofs.

In this chapter, the contribution of green roofs in management of the urban water cycle is addressed. Primarily, proper water management strategies are presented, with specific regard to the sustainable practice of irrigation and the definition of water quality standards. We reference the application of alternative water sources, such as rainwater harvesting and gray water regeneration. Then, the environmental, ecological, and financial benefits associated with rooftop greening are described, including reference to life cycle cost assessment. Ecosystem service provision is analyzed in specific relation to the role played by water in improving urban microclimate and air quality and promoting resilience to climate change

Design of extensive green roofs for the major school plants of Piraeus

Despite the increase of global awareness regarding environment related issues and the development of relevant international policies; effective activities to conserve open space remain inconsistent in Mediterranean cities. Additionally as urban areas continue to expand and free space at street level becomes more and more limited there is a greater need for innovative green technologies which could contribute to the creation of sustainable urban ecosystems. Green roofs on buildings have already proved valuable for storm water management, energy conservation, microclimate mitigation, pollution remediation and biodiversity restoration, but their spreading in Mediterranean cities is still very limited. The shallow-substrate extensive type of green roofs is of great interest for massive application, which would lead to great scale positive effects in urban ecosystems. In Greece, in the framework of a relevant initiative called "Green roofs on public buildings", pilot extensive green roofs for the four major school plants of the city of Piraeus were designed. These green roofs which have a total area of about 0.6 ha are located in highly populated districts with negligible green spaces. This presentation is focusing on the decision making processes during the design and the selection of the growing medium and the planting material. The methods and the parameters of the relevant landscape, bioclimatic, hydrologic, irrigation and drainage studies are also presented. It is expected that the construction of these green roofs will improve the life quality of the school communities and more generally of the citizens of Piraeus

Estimation of Monthly FAO Penman-Monteith Evapotranspiration in GIS Environment, through a Geometry Independent Algorithm

AbstractThe purpose of this study was to implement the monthly FAO Penman-Monteith evapotranspiration estimation method in a GIS environment, given the importance of spatial estimation of the evapotranspiration in the rational management of water resources and also the lack of easily applicable methodology in GIS environment. In this context, a Python programming language script was developed for implementing monthly FAO Penman-Monteith evapotranspiration equation, in ESRI's ArcMap environment. This approach has the advantage of being independent of the type of geospatial data and can be applied in point, line and polygon data while at the same time being flexible and time saving without loss of accuracy. The methodology was applied using meteorological data of the 2011 irrigation period (March to September), acquired from the meteorological station located at the campus of Technological Educational Institute of Western Greece at Messolonghi (38o 21’ 58” N; 21o 28’ 41” E), with the results being very satisfactory

Measurements and simulation of microclimatic effects of a horizontal hydroponic pergola

The microclimate model ENVI-met (V4) was used for predicting the effects of different systems of planted pergolas on the microclimate of an atrium. The model was firstly validated using experimental data and then used for different cases studies. The microclimate measurements were carried in a real construction project of a hydroponic pergola at Kostakii Campus of the Technological Education Institute of Epirus (Arta, Greece). The validation results showed a very good agreement between measured and simulated values of air temperature. The model was used to predict the effects on air temperature (Tair), relative humidity (RH), mean radiant temperature (Tmrt) and Physiologically Equivalent Temperature (PET) when of 0%, 50% and 100% of the atrium horizontal plane area was covered by the planted pergola. The results showed that compared to the case with no pergola in the atrium, covering 100% the atrium area with a planted pergola reduced average Tair up to 0.78 and 1.3 °C during the day and night, respectively, while at the hottest time of day, Tmrt was lowered 29.4 °C and the PET was lowered up to 17.9 °C. © 2015 for this paper by its authors

Microclimatic effects of planted hydroponic structures in urban environment: measurements and simulations

The objectives of this effort was to study the effect of vertical (green wall) and horizontal (pergola) green structures on the microclimate conditions of the building surroundings and estimate the thermal perception and heat stress conditions near the two structures. The experimental data were used to validate the results simulated by the recent version (V4.0 preview III) of ENVI-met software which was used to simulate the effect of different design parameters of a pergola and a green façade on microclimate and heat stress conditions. Further aim is to use these results for better design of green structures. The microclimate measurements were carried out in real scale structures (hydroponic pergola and hydroponic green wall) at the Kostakii Campus of the Technological Education Institute of Epirus (Arta, Greece). The validation results showed a very good agreement between measured and simulated values of air temperature, with Tair,sim = 0.98 Tair,meas in the Empty atrium and Tair,sim = 0.99 Tair,meas in the Atrium with pergola, with a determination coefficient R2 of 0.98 and 0.93, respectively. The model was used to predict the effects of green structures on air temperature (Tair), relative humidity (RH), and mean radiant temperature (Tmrt). The output values of these parameters were used as input data in the RayMan pro (V 2.1) model for estimating the physiologically equivalent temperature (PET) of different case scenarios. The average daytime value of simulated air temperature in the atrium for the case without and with pergola during three different days was 29.2 and 28.9 °C while the corresponding measured values were 29.7 and 29.2 °C. The results showed that compared to the case with no pergola in the atrium, covering 100% the atrium area with a planted pergola reduced at the hottest part of the day Tmrt and PET values by 29.4 and 17.9 °C, respectively. Although the values of air temperature (measured and simulated) were not greatly affected by the presence of a green wall, the most important effect of green wall to the building wall is the reduction of solar radiation behind the green wall. This reduction leads to a significant reduction (about 8 °C) of building surface temperature behind the green wall and accordingly to a reduction of the energy load of the building. © 2016, ISB