2008年5-11月,对黄河口滨岸潮滩不同生境下翅碱蓬(Suaeda salsa)硫(S)的季节变化特征进行了研究。研究表明:中潮滩翅碱蓬(JP1)和低潮滩翅碱蓬(JP2)各器官生物量均具有明显的季节变化特征,总体表现为JP1〉JP2;JP1和JP2地上与地下部分比值的变化较为一致,整体表现为JP2〉JP1;二者枯落物量呈递增变化;JP1和JP2叶、茎和枯落物中的全硫(TS)含量在生长季波动变化明显,整体呈先增后减变化,而根中的TS含量在生长季呈递减变化,符合指数衰减模型;二者不同器官及枯落物的TS累积量和S累积速率(VS)季节变化明显,JP1地上部分的TS累积量和VS明显高于JP2,且二者地上部分的TS累积量和VS均明显高于地下;JP1和JP2不同部分的S分配比差异明显,其中叶的分配比最高,分别为(38.34±16.19)%和(66.27±12.09)%,说明叶是翅碱蓬重要的S累积器官。结果显示,翅碱蓬的生态学特性和其所处生境的水盐状况对JP1和JP2生物量、TS含量、累积量、累积速率、分配比均具有重要影响。
Aims Our objective was to determine the characteristics of sulfur (S) accumulation and allocation by Suaeda salsa in two different habitats of the intertidal zone in the Yellow River Estuary of China. Methods We established two plots (30 m × 30 m) in two different tidal flats and collected different organs of S. salsa every 20 days from May to November 2008 from four or five sites selected at random from the two plots. Important findings The biomass of different organs of S. salsa in middle tidal flat (JP1) and low tidal flat (JP2) showed significant seasonal dynamics, and the values of JP1 tended to be higher than those of JP2. For JP1 and JP2, the ratios of aboveground biomass to belowground biomass changed similarly, but the values of JP2 tended to be larger than those of JP1. The litter biomass of JP1 and JP2 increased exponentially during the growing season. Although the total sulfur (TS) contents in leaves, stems or litter of JP1 and JP2 fluctuated greatly during the growing season, they all initially increased and then decreased. In comparison, values in roots decreased at all times following an exponential decay model. The TS accumulation amount and rate (VS) of different organs and litter also had seasonal changes, and the values of above-ground organs of JP1 were much higher than those of JP2. Moreover, the TS accumulation amount and VS of above-ground parts were higher than those of below-ground parts. The S allocation ratios of different parts of JP1 and JP2 also had significant differences. Leaves had the highest allocation ratio, and values of JP1 and JP2 were (38.34 ± 16.19)% and (66.27 ± 12.09)%, respectively, indicating that leaves were the most important site of S storage.