【摘要】 红树林(Mangroves)是生长在热带和亚热带海岸潮间带的木本植物群落。老鼠簕(Acanthus ilicifolius)是我国红树林林下灌丛的主要物种,是林下植被碳库的主要构成成分。本研究选取深圳福田红树林区的林下、林窗、林缘和光滩等不同生境下自然生长的老鼠簕植株,测定植株生物量和光合特性等相关指标。研究表明,林窗生境下的老鼠簕植株的光合能力、光合固碳速率和地上生物量累积均达到最大;林下生境最不利于老鼠簕植株固碳;光滩的老鼠簕植株具有较高的地下生物量累积,但由于其蒸腾速率高、水分利用率低下,其固碳较低。光照强度是决定不同生境老鼠簕植株固碳的关键因子。在未来我国红树林造林中,老鼠簕可作为林下植被构建,以提高红树林生物量总碳库,但最适宜老鼠簕固碳的光照约为40%～80%。本文研究结果将为红树林造林实践中的物种选择和林分构建提供理论参考。更多还原

【Abstract】 Mangroves are woody communities naturally distributed along the coastal line of tropical and subtropical regions. As the major under-forest species in mangroves of China, Acanthus ilicifolius is one of the major components of vegetative carbon stock in mangroves. This study aimed to discover the growth and leaf assimilation traits of Acanthus ilicifolius in different environments in natural mangroves, which were two kinds of environments under dense canopy of Kandelia obovata and Avicennia marina forests, forest gaps, forest edges and the mudflats. The results show that the leaf assimilation capacities, assimilation rates and aboveground biomass reached the maximum in forest gaps and forest edges among the five environments. The two understory environments were not suitable for Acanthus ilicifolius carbon accumulation. Although Acanthus ilicifolius in mudflats maintained the highest belowground biomass, the highest transpiration rates and the lowest water use efficiency depressed the total biomass. Light intensity was the key among all environmental factors contributing to carbon assimilation of Acanthus ilicifolius vegetation. In future mangrove reforestation, Acanthus ilicifolius vegetation could act as an understory carbon stock and contribute to total vegetative carbon stocks of mangroves.However, around 40% to 80% of light intensity would be the most suitable for Acanthus ilicifolius carbon assimilation. The results obtained in this paper provide a reference for species selection and forest structure establishment in mangrove afforestation in China.更多还原