双台子河口文蛤碳、氮、磷收支的季节变化

在双台子河口现场研究滩涂生境优势埋栖性贝类--文蛤主要生理生态学参数的基础上，建立了其不同季节的C、N、P收支方程.结果表明，文蛤对海水中C、N、P等要素的生长余力（SFG_C、SFG_N、SFG_P）均呈现明显的季节变化，即在夏季最高；但SFG_C在春季时最低，且为负值，SFG_N及SFG_P全年均为正值.SFG_C、SFG_N和SFG_P变化范围分别为-2.11~18.59mgC/（ind·d）、0.13~5.87mgN/（ind·d）和0.11~1.45mgP/（ind·d）.文蛤的C、N、P生长效率季节变化显著，且C、N、P净生长效率基本表现为K_N2 > K_P2 > K_C2.文蛤在春季及秋季时的碳收支顺序依次为粪便碳 > 呼吸碳 > 生长碳，夏季时为生长碳 > 呼吸碳 > 粪便碳，冬季时为生长碳 > 粪便碳 > 呼吸碳.文蛤摄取氮元素用于生理过程的各组分比例依次为生长氮 > 粪便氮 > 排泄氮.文蛤摄食磷量用于生理过程的各组分比例在各季节中（除冬季外）依次为生长磷 > 粪便磷 > 排泄磷.C、N、P收支方程显示，文蛤更趋向于对N、P元素的富集，即摄取的N、P元素绝大部分用于其自身的生长和繁殖.研究结果表明，文蛤作为双台子河口优势埋栖性贝类是该海域生态系统C、N、P循环的重要组成部分，并在河口生态系统生源要素循环中发挥着重要作用.

Seasonal variation in carbon,nitrogen, and phosphorus budgets of the hard clam Meretrix meretrix in Shuangtaizi estuary

The seasonal filtration, ingestion and biodeposition rates were in situ measured, and carbon (C), nitrogen (N) and phosphorus (P) budgets of Meretrix meretrix throughout the year were modeled. The results indicated that the scope for growth of M. meretrix in carbon (SFG_C), nitrogen (SFG_N), and phosphorus (SFG_P) all ranged significantly among seasons, and the peak values were detected in summer. Among them, SFG_Cwas negative in spring, SFG_N and SFG_P were always positive thorough the year. The seasonal ranges of SFG_C, SFG_N, and SFG_P were -2.11~18.59mg C/(ind·d), 0.13~5.87mg N/(ind·d), and 0.11~1.45mg P/(ind·d), respectively. Distinct seasonal patterns were shown among the net growth efficiencies in carbon (K_C2), nitrogen (K_N2), and phosphorus (K_P2), and ranked as K_N2 > K_P2 > K_C2. Furthermore, the carbon budgets in spring and autumn was in the following order:the C loss from fecal production (F_C) > the C loss from respiration (E_C) > the C loss from growth (G_C), and in summer was in the following order: G_C > E_C > F_C, in winter was in the following order: G_C > F_C > E_C. The nitrogen and phosphorus budgets were ranked as follows:the N used for growth (G_N) > the N loss from fecal production (F_N) > the N loss from excretion (E_N), The P used for growth (G_P) > the P loss from fecal production (F_P) > the P loss during excretion (E_P), respectively. The C, N, and P budgets illustrated that more N and P than C were consumed for growth and the pelagic primary production was transferred efficiently to a higher trophic level. This study suggests that M. meretrix population may play a key role in the nutrient cycle of the estuarine ecosystem, and should be considered an important component of the ecology of estuaries.