测定了福建红树植物秋茄（kAndElIACAndEl（l.）druCE）各季节落叶分解碎屑中水解有效能（HAC）、无丹宁水解有效能（TfHAC）和化学有效能（CAC）的绝对含量和相对含量。测定结果表明：落叶中有效能的绝对含量和它占总能量的百分含量的季均值是：HAC4.06kJ/gdW，20.85%；TfHAC3.32kJ/gdW，16.68%。在半分解（失重率为50%）的碎屑中它们降为HAC1.75kJ/gdW，9.25%；TfHAC1.64kJ/gdW，8.20%。HAC与TfHAC之间的差异随着落叶的分解而减小。碎屑中CAC的含量在分解过程中趋于提高，而且数值总是大于HAC和TfHAC，表明碎屑中有些蛋白和脂肪的能量因难被稀酸水解，对食碎屑动物而言是无效的。HAC的热值在初始干重损失百分率小于23%的碎屑中波动于16.16~17.41kJ/gAfdW（去灰分干重），在进一步分解的碎屑中迅速提高，最大值（24.05kJ/gAfdW）出现在初始干重损失百分率为49.44%的碎屑中。与其它海洋植物的碎屑相比，红树植物落叶分解碎屑中有效能含量低，有效能热值居中。最后讨论了HAC、TfH？The absolute and relative contents of hydrolysis available calories (HAC),tannin Free HAC (TFHAC) and chemical available calories (CAC) of the detritus during the seasonal decomposition of mangrove (Kandelia candel (L.) Druce) leaF litter in Fujian,China was determined.DeFined arbitrarily as the portion of total caloric content in detritus hydrolized with 1 mol/L HCl For 6 h at 20 ℃,HAC is presumed to be a rough index of potential energy readily utilized by marine detritivores.TFHAC is the remaining calories of HAC devoid of tannin attributed calories and CAC is deFined as the total caloric content derived From raw protein,raw Fat and soluble sugar.The results showed that in leaF litter, the seasonal mean caloric contents were 4.06 kJ/g DW or 20.85% of the total caloric content For HAC and 3.23 kJ/g DW or 16.68% of the total caloric content For TFHAC,which decreased to 1.75 kJ/g DW or 9.25% For HAC,and l.64 kJ/g DW or 8.20% For TFHAC in the detritus at halF liFe of decomposition.The diFFerence in contents between HAC and TFHAC diminished as decomposition was progressed.The contents of CAC generally increased during decomposition,always higher than those of HAC and TFHAC,suggesting that some protein and Fat in detritus are nonavailable to detritivores since they are hydrolyzed by week acid.The value of detritus HAC per unit ash Free dry weight (AFDW),as determined at the time when the detritus lost 23% of its initial weight,ranged From 16.16 to 17 41 kJ/g AFDW and increased rapidly to a maximum of 24.00 kJ/ g AFDW at 49% dry weight loss of detritus during decomposition.The detritus derived From mangrove Fallen leaves had a low available caloric content and an moderate caloric value of HAC as compared with detritus of other marine plants.Finally,the relationship between HAC,TFHAC and CAC was discussed and some points of attention relevant to the application of those indices were given in relation国家自然科学基
