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The contribution of integrated municipal solid waste (MSW) management systems to greenhouse gas emissions is not negligible, even though it is moderate compared with other anthropogenic activities. The main emission from landfills that accept biodegradable MSW is methane that escapes from the biogas collection system. Such emissions are partially compensated if the collected biogas is exploited for energy production. Further compensation measures would also increase the overall sustainability of the landfill site. This study analyses the possibility of exploiting closed landfills to produce energy based on the case study of the Valdina landfill (Messina, Italy). Two possible scenarios are presented: the installation of a photovoltaic system and the cultivation of giant reed (Arundo donax L.) to be used for energy production through combustion. The results of a preliminary experimental activity are presented for the second scenario. The findings demonstrate the possibility of using the leachate produced in the landfill for irrigation purposes. For each scenario, the costs, potential energy production rate, avoided emissions and issues related to the integration of energy production with the landfill aftercare are evaluated. The presented results suggest that the cultivation of giant reed is the best option, especially during the early post-closure period, in terms of investment (18,000 € against 8,300,000 €), high production yield in the Mediterranean climate, simplicity of cultivation and integration with ordinary post-closure landfill management, limited cost of the energy produced (0.1€ kWh^-1 against 0.27€ kWh^-1). On the other hand avoided emissions are higher for the photovoltaic plant (27804  against 778  on an horizon of 20 years).

Two greenhouse pot experiments were conducted in Agrinion, Greece. The impact of treated municipal wastewater (TMWW) and sludge (i) on the growth of Lactuca sativa L. var Longifolia (lettuce) and (ii) on the extent of soil pollution with heavy metals was studied. Soil pollution was assessed by calculating the Pollution Load Index (PLI). Both of these experiments were conducted, using a randomized block design in four replications and seven treatments, respectively, as follows: (a) Experiment A: study of the effect of treated municipal wastewater (TMWW): [Control, 20%, 40%, 60%, 80%, 100%, (100%+30 t/ha Sludge)] and (b) Experiment B: Study of the effect of sludge (t/ha): 0,  6, 12,  18, 24 , 30, (30+100%TMWW). The sludge affected significantly plant height and fresh and dry matter yield, as well as the dry matter N content of plants, while the TMWW affected significantly the dry matter yield and non-significantly the plant height. The pollution load index (PLI) was non-significant for both treatments (sludge and TMWW). According to PLI calibration scale, the soil was found to be slightly polluted with heavy metals under both treatments.

The present study analyses future climate uncertainty for the 21st century over Tamilnadu state for six weather parameters: solar radiation, maximum temperature, minimum temperature, relative humidity, wind speed and rainfall. The climate projection data was dynamically downscaled using high resolution regional climate models, PRECIS and RegCM4 at 0.22°x0.22° resolution. PRECIS RCM was driven by HadCM3Q ensembles (HQ0, HQ1, HQ3, HQ16) lateral boundary conditions (LBCs) and RegCM4 driven by ECHAM5 LBCs for 130 years (1971-2100). The deviations in weather variables between 2091-2100 decade and the base years (1971-2000) were calculated for all grids of Tamilnadu for ascertaining the uncertainty. These deviations indicated that all model members projected no appreciable difference in relative humidity, wind speed and solar radiation. The temperature (maximum and minimum) however showed a definite increasing trend with 1.8 to 4.0°C and 2.0 to 4.8°C, respectively. The model members for rainfall exhibited a high uncertainty as they projected high negative and positive deviations (-379 to 854 mm). The spatial representation of maximum and minimum temperature indicated a definite rhythm of increment from coastal area to inland. However, variability in projected rainfall was noticed.