【作者】 彭胜；

【导师】 范航清；

【作者基本信息】 广西大学 ， 生态学， 2007， 硕士

【摘要】 海草与红树林和珊瑚礁并称为三大典型海洋生态系统，它是生活于热带和温带海域浅水中的单子叶植物，是只适应于海洋环境生活的水生种子植物。本研究对广西防城港珍珠湾海草床矮大叶藻群落进行了一整年的生物量和热值的研究，并对矮大叶藻的不同发育阶段和四种不同海草的热值进行的比较研究。本论文研究填补了广西海草的基础科学数据、并为保护恢复和合理利用方面提供了科学依据。1、矮大叶藻地上全年平均生物量为21.97 g．DW．m^-2，地下的全年平均生物量是24.53 g．DW．m^-2，一年每个月份的变化趋势也相差不多，4月的生物量最大，8月最小。地上部与地下部生物量的比值3月、4月、7月、8月的比值1，其他月份小于1。矮大叶藻呈现出越向向海面的生物量越高，且是个明显的变化趋势。2、矮大叶藻地上全年平均干重热值是13.43 kJ／g，平均的灰分含量17.03％，平均去灰分热值为16.22 kJ／g地下平均干质量热值是12.33 kJ／g，平均的灰分含量21.72％，平均去灰分热值为15.76kJ／g。3、眼子菜科的矮大叶藻和海神草干重热值大于水鳖科的海菖蒲和海黾草，而灰分含量矮大叶藻小于其他三种，地上部与地下部的灰分含量大小随海草种的不同而不同。去灰分热值的大小是，海神草＞海黾草＞矮大叶藻＞海（艹昌）蒲。4、矮大叶藻成熟的叶、茎的干重热值高于幼的叶、茎和老的叶、茎。随着发育过程，叶片的灰分含量越来越高，茎的灰分含量越来越少。去灰分热值最大是成熟叶16.57 kJ／g，最小的是老茎14.19 kJ／g。5、矮大叶藻叶片的N／P秋、冬季较大，达到16，春季较低为10.2，茎的N／P秋季最大11.8，最小的是春季为4.9。四种海草的N、P含量均较高，叶片的N含量大于茎中的，但P含量随海草种不同而不同。矮大叶藻随着发育过程，N、P含量逐渐增加。更多还原

【Abstract】 Seagrass bed is one kind of the representative marine ecosystems like mangrove, coral reefs and so on. Being a category of Monocotyledons in the shallow water, they are adapted well to the marine habitats. My research was designed to study: （1） the year-round dynamics in the biomass and caloric value of Zostera japonica seagrass meadow in Zhenzhu Bay, Fangchenggang city, Guangxi province; （2） The caloric values of Zostera japonica in the different development stages; And （3） comparison of the caloric values in four species of seagrass in Southern China. The goal of this study was to provide with scientific data for the protection, restoration and sustainable utilization of seagrass in China.The results are as follow:1. The average year-round biomass of aboveground organs in Zostera japonica was 21.97 g.DW.m^-2, and that in the underground organs was 24.53 g. DW. m^-2. It seemed that the biomass changed evenly through the whole year, it was however higher in April and lower in August. The ratios of the aboveground biomass to the underground were higher than 1 in March, April, July and August, while those were lower than 1 in other months. The biomass of Zostera japonica increased significantly with the increasing distance off the shore.2. In the aboveground part of Zostera japonica, the average year-round gross caloric value was 13.43kJ/g, the average ash free caloric value 16.22 kJ/g and the average ash content 17.03%. And in the underground part, the average year-round gross caloric value was 12.33 kJ/g, the average ash free caloric value 15.76 kJ/g and the average ash content 21.72%.3. The gross caloric values in Zostera japonica and Cymodocea rotundata （two species in family Potamogetonaceae） were higher than those in Enhalus acoroides and Thalassia hemperichii （two species in family Hydrocharitaceae）. The ash contents varied among these four species, with the lowest recorded in Zostera japonica. The decreasing order in the ash-free caloric values was Cymodocea rotundata, Thalassia hemperichii, Zostera japonica and Enhalus acoroides.4. The gross caloric values in mature leaf and stem were higher than those in young leaf and stem in Zostera japonica. Along with the aging process, the ash content in leaf increased, while those in stem decreased. The maximum of ash free caloric value occurred in the mature leaf, 16.57kJ/g, and the minimum in old stem, 14.19kJ/g.5. The N/P ratios in leaf of Zostera japonica were 16 in autumn and winter, 10.2 in spring. The N/P ratios in stem were highest in autumn, 11.8, and lowest in spring, 4.9. In contrast to other plants, the contents of N and P in these four species of seagrass were higher. The N contents in leaves were always higher than those in stems, but the P contents did not obey the same rule as the N contents. Both the N and P contents increased along with the aging process.更多还原