Annual Greenhouse-Gas Emissions from Forest Soil of a Peri-Urban Conifer Forest in Greece under Different Thinning Intensities and Their Climate-Change Mitigation Potential

Abstract

Knowledge of the response of thinning implementation on forest soil–atmospheric greenhouse gas (GHG) (CO2, CH4, N2O) fluxes exchange system in Mediterranean region is limited because of the high heterogeneity of both soil properties and forest biomass. The novelty of this study is grounded predominantly in evaluating for the first time the response of annual GHG fluxes to thinning in a coniferous peri-urban forest soil in Greece, thus contributing significantly to the enrichment of the GHG fluxes database from the Mediterranean forest ecosystem. Results suggest that CH4 uptake increased with increasing thinning intensity. The reduction in CO2 emissions in both thinning treatments was possibly related to an indirect effect of soil heterotrophic and autotrophic respiration. Coniferous peri-urban forests in Greece can act temporally as sinks of atmospheric N2O in the coldest months and a weak source of N2O fluxes in summer. The GHG variation depended largely on soil environmental factors with soil temperature representing the dominant factor for CO2 and CH4, whereas soil moisture correlated, albeit weakly, with N2O variability. Reduction in global warming potential was observed in both thinning treatments, markedly in selective treatment, giving an initial indication that high-intensity thinning in coniferous peri-urban forests in Greece presents a high potential for global change mitigation.

Investigating the Citizens’ Views and Perceptions About the Urban Forest Infrastructure and Services of Komotini, Greece

“…The necessity to create a forest inventory across Europe is underlined by Buras and Menzel [11], stressing the need for protecting and properly managing the fragile forest ecosystems in Italy and France. In the same ground, Doukalianou et al [12], highlight the importance of Mediterranean forests in mitigating climate effects. Martínez-Jauregui et.…”

New Silvicultural Treatments for Conifer Peri-Urban Forests Having Broadleaves in the Understory - The First Application in the Peri-Urban of Xanthi in Northeastern Greece

“…It covers an area of about 2400 ha, in an elevation range of 100 to 630 m. In the periurban forest there are reforestations -plantations that began in 1936 and lasted up to 2007. However, most of them were established before 1973 [9,10]. The reforestations cover a great part of the peri-urban forest.…”

“…The mean annual precipitation in the area of Xanthi is 675 mm while the mean annual temperature is 15.5oC [13]. In the areas where the treatments that are analyzed in this study were applied, the soil texture is sandy clay to sandy clay loam [10]. The treatments were applied in a part of reforestations that was established (mainly) in the decade of 1950 ( Figure 1).…”

“…According to Doukalianou et al [10], both types of silvicultural treatments reduced the potential of global warming. However, they mentioned that there is an indication that the selective treatments, which were high-intensity treatments, exhibit a high potential for the mitigation of global change.…”

“…In the context of The FoResMit Project (LIFE14 CCM/ IT/905 "Recovery of degraded coniferous Forests for environmental sustainability Restoration and climate change Mitigation"), new selective silvicultural treatments were developed in Monte Morello peri-urban forest in Italy and in the peri-urban forest of Xanthi in Greece and were applied together with the traditional silvicultural approaches [9,10]. In Xanthi, the proposed silvicultural treatments target in the fast conversion of the peri-urban forest in a broadleaf forest or in a mixed conifer-broadleaf forest, and thus are expected to exhibit high intensity.…”