Biomass Allocation of Scirpus mariqueter Along an Elevational Gradient in a Salt Marsh of the Yangtse River Estuary

Scirpus mariqueter Tang et Zhang is a typical pioneer plant colonizing the bare beaches of the Yangtse River estuary. To explore the life history strategy of the species with reference to environmental physical stress, the biomass allocations to different plant components and some related morphological parameters were examined along an elevational gradient within a salt marsh. Authors found that S. mariqueter performed best at medium elevation within the marsh, with relatively high density of shoot and individual ramet dry mass. Biomass allocation to corm was the highest at low elevations, and the least at high elevations, suggesting that a conservative strategy was adopted by the species to cope with the harsh physical conditions at the low elevation. The investment in rhizome decreased from low to high elevations, while the proportion of inflorescence mass increased, indicating that during the life history, the species shifts from predominant asexual reproduction to predominant sexual reproduction. This may be favourable for the species to colonize larger area, and to spread and persist at a meta_population level. Correlation analyses showed that sexual reproduction was inversely related to growth and asexual reproduction. However, it is difficult to determine the relationship between asexual reproduction and growth possibly because of the varied function of the corms of the species in different life history stages.

问吧问吧

标本中的模范生。长得一模一样的标本。专家解惑模式标本,即作为规定的典型标本。以鱼类为例,鱼的种类繁多,各地的叫法也千差万别。为了让这些称呼与其所指的物种之间有固定的查核依据,每确立一个新鱼种时,除了用必要的文字描述及图表解释外,还需将确定鱼种学名时所使用的标本特别收藏,作为今后稽考的关键资料,这种鱼类标本就是模式标本。