宁夏4种灌木光合固碳能力的比较

通过对叶片光合速率及植株生物量的测定，研究了宁夏4种常见灌木的固碳潜力。结果表明，从4种灌木单个叶片的光合角度研究固碳能力，生长旺盛季（7月）表现为互叶醉鱼草（Buddleja alternifolia）>蒙古扁桃（Amygdalus mongolica）>沙木蓼（Atraphaxis bracteata）>宁夏枸杞（Lycium barbarum）；全生长季为宁夏枸杞>互叶醉鱼草>沙木蓼>蒙古扁桃。经过对4种灌木的单位叶面积和全株叶面积的测定，研究了全株灌木的固碳潜力，结果显示，不论是7月的全株日均碳同化量还是全生长季的全株日均碳同化量，都表现出互叶醉鱼草>宁夏枸杞>沙木蓼>蒙古扁桃的规律，与生物量测定的结果完全吻合。说明，从植物光合角度研究固碳能力有必要从全株叶片水平的光合进行考虑。另外，由于宁夏枸杞经济林具有良好的水肥管理措施，推测经济林有较强的固碳能力，应予以重视。

A comparison of photosynthetic carbon sequestration of four shrubs in Ningxia

Carbon sequestration of four kinds shrubs in Ningxia was studied by testing leaf photosynthetic rate and plant biomass.The results indicated that if the research was on photosynthesis of each individual leaf,carbon sequestration was in the order of Buddleja alternifolia>Amygdalus mongolica>Atraphaxis bracteata>Lycium barbarum in the vigorous growth season(in July);or L.barbarum>B.alternifolia>A.bracteata>A.mongolica in the whole growth season.We also measured a single-leaf area,the area of whole plant leaves and the carbon sequestration of whole plant.The results indicated that sequence of the average daily amount of carbon assimilation of the whole plant was B.alternifolia>L.barbarum>A.bracteata>A.mongolica in both of the vigorous growth season and the whole growth season.The similar results were obtained on the measurement of biomass.Therefore,it can be concluded that the plant carbon sequestration in whole plant leaves should be considered if the photosynthetic rate is used as a testing target.In addition,it should be paid attention that there is a strong carbon sequestration of L.barbarum forests due to the good maintenance,such as irrigation and fertilizer.