The paper deals with the geological setting, history and subsidence of the Venetian Plain. Major attention is paid to the Pleistocene-Holocene stratigraphic sequence in the Lagoon of Venice, in relation to its orig...The paper deals with the geological setting, history and subsidence of the Venetian Plain. Major attention is paid to the Pleistocene-Holocene stratigraphic sequence in the Lagoon of Venice, in relation to its origin that datesback to 6-7 kyr BP. Geological land subsidence, which played an important role in the origin and the evolution of the lagoon, and anthropogenic subsidence, that has recently assumed a major importance for the Venetian environment, are discussed. Considering also the sealevel rise, 23 cm loss in land elevation has occurred in the last century, leading to increased flooding events and environmental problems that require protective works.展开更多
Most of the sedimentary rocks occurring in Italy are post-Carboniferous. All what lies below is considered basement, mostly metamorphic or igneous. Understand-ing the pre-Carboniferous evolution depends on the recon...Most of the sedimentary rocks occurring in Italy are post-Carboniferous. All what lies below is considered basement, mostly metamorphic or igneous. Understand-ing the pre-Carboniferous evolution depends on the reconstruction of the sedimentary, metamorphic and igneous evolution of the basement. In general, the base-ment sedimentary protoliths were Lower to Middle Pale-ozoic siliciclastic rocks, while the igneous protolithsbelong to an Ordovician cycle. The prevailing metamor-phism,from very-low grade to granulite facies, is Variscan. It was followed by the formation of large amounts of granitic melts.展开更多
All plants emit a wide range of volatile compounds, the so-called biogenic volatile organic compounds(BVOC). BVOC emissions have received increased scientific attention in the last two decades because theymay profound...All plants emit a wide range of volatile compounds, the so-called biogenic volatile organic compounds(BVOC). BVOC emissions have received increased scientific attention in the last two decades because theymay profoundly influence the chemical and physical properties of the atmosphere, and may modulate planttolerance to heat, pollutants, oxidative stress and abiotic stresses, and affect plant-plant and plant-insectinteractions. Urban forestry may have a high impact on atmospheric composition, air quality, environment,and quality of life in urban areas. However, few studies have been carried out where the emission of BVOCcould have important consequence for the quality of air and contribute to pollution episodes. A screening ofBVOC emission by the mixed stand constituting urban forests is therefore required if emissions are to bereliably predicted. Monitoring the emission rates simultaneously with measurements of air quality, plantphysiology and micrometeorology on selected urban forests, will allow detailed quantitative information onthe inventory of BVOC emissions by urban vegetation to be compiled. This information will make itpossible to propose an innovative management of urban vegetation in cities characterised by heavy emissionsof anthropogenic pollutants, aiming at the abatement of BVOC emissions through the introduction or selectionof non-BVOC emitting species in urban areas subjected to pollution episodes and in the new afforestationareas covering peri-urban parks, green belts and green corridors between peri-urban rural areas and theconurbations.展开更多
文摘The paper deals with the geological setting, history and subsidence of the Venetian Plain. Major attention is paid to the Pleistocene-Holocene stratigraphic sequence in the Lagoon of Venice, in relation to its origin that datesback to 6-7 kyr BP. Geological land subsidence, which played an important role in the origin and the evolution of the lagoon, and anthropogenic subsidence, that has recently assumed a major importance for the Venetian environment, are discussed. Considering also the sealevel rise, 23 cm loss in land elevation has occurred in the last century, leading to increased flooding events and environmental problems that require protective works.
文摘Most of the sedimentary rocks occurring in Italy are post-Carboniferous. All what lies below is considered basement, mostly metamorphic or igneous. Understand-ing the pre-Carboniferous evolution depends on the reconstruction of the sedimentary, metamorphic and igneous evolution of the basement. In general, the base-ment sedimentary protoliths were Lower to Middle Pale-ozoic siliciclastic rocks, while the igneous protolithsbelong to an Ordovician cycle. The prevailing metamor-phism,from very-low grade to granulite facies, is Variscan. It was followed by the formation of large amounts of granitic melts.
文摘All plants emit a wide range of volatile compounds, the so-called biogenic volatile organic compounds(BVOC). BVOC emissions have received increased scientific attention in the last two decades because theymay profoundly influence the chemical and physical properties of the atmosphere, and may modulate planttolerance to heat, pollutants, oxidative stress and abiotic stresses, and affect plant-plant and plant-insectinteractions. Urban forestry may have a high impact on atmospheric composition, air quality, environment,and quality of life in urban areas. However, few studies have been carried out where the emission of BVOCcould have important consequence for the quality of air and contribute to pollution episodes. A screening ofBVOC emission by the mixed stand constituting urban forests is therefore required if emissions are to bereliably predicted. Monitoring the emission rates simultaneously with measurements of air quality, plantphysiology and micrometeorology on selected urban forests, will allow detailed quantitative information onthe inventory of BVOC emissions by urban vegetation to be compiled. This information will make itpossible to propose an innovative management of urban vegetation in cities characterised by heavy emissionsof anthropogenic pollutants, aiming at the abatement of BVOC emissions through the introduction or selectionof non-BVOC emitting species in urban areas subjected to pollution episodes and in the new afforestationareas covering peri-urban parks, green belts and green corridors between peri-urban rural areas and theconurbations.
