Analysis of Carbon Sequestration and Oxygen Release Capabilities of 25 Afforestation Plants in Tianjin

CI-340 portable photosynthesis test system and JYM-B leaf area meter were employed to observe the physiological velocity and leaf area index of 25 widely used afforestation plants in Tianjin. The results indicate that the diurnal change curve of net photosynthesis rates of 25 experimental species has one or two peaks. The daily carbon sequestration and oxygen release per unit leaf area are respectively 3.98-13.01 g/( m2·d) and 2.9-9.46 g/( m2·d). Among arbors, the order of carbon sequestration and oxygen release capabilities per unit leaf area is Ulmus pumila >Fraxinus velutina>Sophora japonica>Salix matsudana f. pendula>Malus micromalus cv.‘American’>Koelreuteria paniculata>Acer truncatum>Ulmus pumila cv. ‘jinye’>Prunus davidiana>Malus micromalus>Cotinus coggygria > Rhus typhina> Platanus orientalis>Catalpa speciosa>Diospyros kaki> Morus alba cv. ‘Tortuosa’. Among shrubs, the order is Weigela florida>Euonymus japonicus>Cercis chinensis>Ligustrum vicaryi >Sorbaria sorbifolia> Syringa oblata > Lonicera maackii >Cornus alba>Lonicera japonica.