【作者】 WANG JIANING；

【导师】 周红；

【作者基本信息】 中国海洋大学 ， Marine Biology， 2011， 硕士

【摘要】 在一年时间内,按四个季节研究青岛三个人为干扰砂质潮间带:青岛第一海水浴场（一浴）,第二海水浴场（二浴）和第三海水浴场（三浴）的小型底栖生物和沉积环境。取样日期按照季节变化确定,分别是2010年3月（青岛的春季）;2010年7月（夏季）;2010年10月（秋季）;和2011年1月（冬季）。除了这三个取样地点,在2010年6月,一次额外的样品采集选择在排水口进行。小型底栖生物的研究主要关注于小型底栖生物的丰度,生物量和类群组成的时空变化。同时,对沉积环境的研究,主要是现场测量以及记录表层海水和间隙水的盐度,温度,溶解氧和pH值;并且在实验室测定沉积物粒度,叶绿素-a和有机质含量。为了研究有机质富集对小型底栖生物的影响,一个综合研究（现场采样结合小型受控生态系实验）在2010年4月完成。本论文共有三个部分,分别是:1.人为干扰砂质潮间带的沉积环境研究;2.人为干扰砂质潮间带小型底栖生物丰度和生物量的时空变化;3.有机质富集对砂质滩小型底栖生物的影响:现场采样和实验室微宇宙（小型受控实验生态系）实验。沉积环境因子的研究结果显示:三个采样地点都是属于砂质潮间带;而且沉积物的主要成分都是细沙。分选程度均是较好,中值粒径数值（介于1.985和2.434之间）基本上相同;偏态数值基本上接近于。沉积物粒度的测定结果没有出现明显的季节性和地点性变化。二浴和三浴的叶绿素a含量全年变化趋势相似,均是在夏季测出最高值,然而一浴的叶绿素a含量全年最高值出现在秋季。一浴的叶绿素a含量在秋季（绿潮的后暴发期）相比其他的季节和采样地点特别的高,这可能是因为其间绿藻数量的极端增加（绿藻水华）。在秋季,二浴和三浴没有受到绿潮影响,然而它们的叶绿素α含量在夏季（绿潮暴发期）是最高,这说明叶绿素α和绿潮有显著的关系。从秋季到冬季,二浴和三浴的叶绿素α的持续降低表明叶绿素受到温度和太阳辐射强度的影响。三个浴场间,有机质含量的变化趋势（随季节持续降低）均非常相似:三个浴场的有机质含量在春季均较高,但不和其它三个季节有显著不同,表明有机质受到规律的水文环境影响（例如,潮汐,水流运动）。2010年6月的一浴排水口研究表明六月的叶绿素α值（均值: 0.646 mg/kg）很接近夏季值（均值: 0.937 mg/kg）,两者没有显著差异(one-way ANOVA, F_1,11 = 2.687, p = 0.129)。小型底栖生物丰度和生物量的研究显示,一年周期内一浴和三浴的丰度变化模型和它们的生物量是相似的:丰度和生物量存在正相关。在一浴,丰度和生物量的最高值均出现在夏季,接着从夏季开始到冬季持续的减少;不同的是,三浴的丰度和生物量在各个季节交替间都会出现显著的向下或向上的反转变化。然而,二浴的季节性波动变化和其它两个浴场有些微不同:丰度和生物量存在负相关,它们的数值在四季里面相对稳定。通过two-way ANOVA对小型底栖生物丰度的空间性（地点变化:三个浴场）和时间性（季节变化:四个季节）研究发现,地点变化对丰度的影响是不显著的（two-way ANOVA, p = 0.075）,同时,季节变化对丰度的影响也是不显著（two-way ANOVA, p = 0.902）。但是交互作用（地点变化和季节变化）对丰度的影响是显著的（two-way ANOVA, p = 0.002）。Pearson的相关分析说明:丰度和叶绿素α负相关;生物量和盐度正相关,并且和温度负相关。根据这个结果,针对三个浴场的丰度和叶绿素α的季节性变化,本文做了画图分析:从夏季到秋季,只有一浴的小型底栖生物丰度出现急剧的减少,这和同时期其他两个浴场不同。这个发现说明夏季和秋季间的一浴出现高强度的人为干扰（例如旅游;绿潮的暴发和后暴发期）,它们可能使得叶绿素α增加和小型底栖生物丰度降低。通过对小型底栖生物的类群组成和垂直分布的分析和测定发现,它们均按照季节性和空间性变化。在每个季节和采样点,线虫是绝对优势类群,桡足类和多毛类是另外两个主要类群。此外,还有介形类,刺胞动物水螅,涟虫,端足类,动吻类,缓步动物,涡虫和双壳类。由于小型底栖生物的季节性变化,一些种类的丰度会在某一个季节比其它季节更高。本研究中的三个采样点的类群组成的变化趋势彼此类似。小型底栖生物垂直分布的时空变化是类似的,它们的丰度在（0-4）厘米层最高,并且随样品深度的增加而减少。在冬季的一浴和二浴,生物的相对丰度在（0-4）厘米层显著减少。这说明低温对小型底栖生物有直接的影响,并且迫使它们向下移动来保持热量。然而,这个现象没有在三浴的冬季出现。在一浴排水口的小型底栖生物的垂直分布非常不同,高丰度总是出现在更深的深度。这可能是由于人为扰动（排水口的淡水排放）:排水的水文运动降低了表面的盐度;并且迫使小型底栖生物向下移动。本论文的最后一个部分是有机质富集对砂质沙滩小型底栖生物的影响:现场采样和实验室微宇宙（小型受控实验生态系）实验。研究的关键是去检验在有机质富集条件下,小型底栖生物丰度是否会受到影响,并且丰度是否会在高有机质富集条件下会比低有机质富集条件下更高。为了检验这个假设,组建了一个为期21天的小型受控实验生态系实验。沉积环境的有机质含量是一个决定性因子并且对小型底栖生物的丰度和多样性是起到关键性的作用。在三种不同有机质含量水平（高有机质,低有机质,对比/参照）中,小型底栖生物和优势类群线虫的丰度都存在着显著不同。然而,丰度在无有机质添加处理组（对比/参照组）中是最高的;对比其他两种处理组的结果,小型底栖生物的总丰度和线虫丰度出现一定程度的降低,同时多样性降低。然而,只有在低有机质处理组的减少程度和对照组比较有统计学意义上的不同。综上,论文的结果说明不仅仅是小型底栖生物的丰度随季节性改变,而且类群组成也随季节变化而变化。一浴,二浴和三浴都是人为干扰的区域,尤其是旅游旺季的一浴受到的影响最大,三个浴场的线虫是最占绝对优势的小型底栖生物类群并且最少受到影响。由于缺少有效数据来支撑和探讨,哪个（些）非生物或是生物因素最能影响小型底栖生物仍然不是很清楚。但是从本论文研究的证据来看,小型底栖生物的时空变化可能更多的是受到叶绿素a,盐度和温度等环境因子的影响,并且也可能受到人为扰动的影响。更多还原

【Abstract】 The meiofauna and its sedimentary environment were investigated seasonally in a one-year period in three bathing beaches of Qingdao （No.1, 2 and 3 bathing beaches） which were subject to various degree of human disturbance. The sampling dates were chosen seasonally in March （spring season in Qingdao）, July （summer）, October （autumn）, 2010 and in January （winter）, 2011. Besides these three sampling locations, an additional samples collection was taken in June, 2010 in the outfall zone of the No.1 bathing beach. The meiofauna studies mainly focused on the spatial-temporal changes of faunal abundance, biomass and group composition. Meanwhile, the studies of sedimentary environments were to measure the salinity, temperature, dissolved oxygen and pH in situ and to measure the particle size of sediment, chlorophyll level and organic content back in laboratory. To study the effects of organic-enrichment on the meiofauna, a combination study of field survey and laboratory microcosm experiment was carried out in April, 2010.There were three sections in this thesis which were:1.Sedimentary environment of the human-disturbed sandy intertidal shores;2.Spatial-temporal changes of meiofauna abundance and biomass in the human-disturbed sandy intertidal shores ;3.Effect of organic-enrichment on sandy beach meiofauna, field study and laboratory microcosm experiment.The results of the sedimentary environmental study showed: three sampling locations were all sandy beaches; and the major components of all sediments were fine sand. The sediments were well sorted; the values of MDφ（between 1.985 and 2.434） were about to be the same; and the values of Ski always closed to zero. The measurement results of the sedimentary particle size did not show obvious seasonal or spatial variations. In No.2 and No.3 bathing beaches, the annual changing trends of chlorophyll-αwere similar with highest values occurred in summer. However, in No.1 bathing beach, the highest value of chlorophyll-αappeared in autumn season. The chlorophyll-αlevel of the No.1 bathing beach in autumn （post-bloom period of the green tide） was found extremely high than other seasons and sampling locations, which may be caused by the dramatically increasing of the stock of green algae （i.e., green algae bloom）. In autumn, No.2 and No.3 bathing beaches seemed not to be affected by green tides, however, the chlorophyll-αlevels in summer （bloom period of the green tide） of those two locations were highest seasonally, this perhaps indicated that chlorophyll-αhas strong relationship with green tide. Besides spring and summer season, the chlorophyll-αdecreased continuously since autumn to winter in No.2 and No.3 bathing beaches, suggesting that the chlorophyll-αlevel was affected by temperature and solar radiation intensity. Among three bathing beaches, the changing trends （continuously decreasing along seasons） of TOM were very closely similar to each other: the values of TOM were all fairly high in spring season in three sampling locations, but not significant different to other three seasons. This may be caused by the low decomposition rate in winter temperature and accumulation of organic matter. In the additional one-off study in the outfall zone of the No.1 bathing beach in June, 2010, the value of the chlorophyll-α（mean: 0.646 mg/kg） was statistically close to the summer value （mean: 0.937 mg/kg）, and they are not statistically different to each other (one-way ANOVA, F_1,11 = 2.687, p = 0.129).The studies on meiofaunal abundance and biomass shows that, in No.1 and 3 bathing beaches, the changing patterns of the meiofaunal abundance in one year period were similar to the ones of the meiofauna biomass: abundance and biomass was positive correlated. In the No.1 bathing beach, both highest abundance and biomass occurred in summer, then decreased continuously since summer to winter; differently, in the No.3 bathing beach, the sharp turning down or up of both abundance and biomass happened along every season. However, the fluctuation patterns of No.2 bathing beach were slightly different to other two bathing beaches: the abundance and biomass was negative correlated, but the values of them were fair stable along four seasons. The two-way crossed ANOVA for meiofaunal abundance comparison among sampling locations （location variability: three bathing beaches） and seasons （seasonality: four seasons） showed that there were no significant effect of the sampling locations on the meiofaunal abundance （two-way ANOVA, p = 0.075）; and no significant effect of the seasons on meiofaunal abundance （two-way ANOVA, p = 0.902） as well. But, significant effects of the interaction （location variability x seasonality） on the meiofaunal abundance （two-way ANOVA, p = 0.002） were detected.The Pearson correlation analysis showed that the meiofauna abundance was negative correlated to chlorophyll a; the biomass was positive correlated to salinity, and negative correlated to temperature. Thus, furthermore graphs of seasonal variations between the abundance and chlorophyllαamong three sampling locations were drawn: from summer to autumn, meiofaunal abundance has a dramatic decreasing only in No.1 bathing beach, this differ to other two bathing beaches in same period. These indicate that some special events （human disturbance, such as tourism and the bloom period and post-bloom period of the green tide） did happen in the No.1 bathing beach during the summer and autumn seasons which may cause the increased chlorophyll level increased and decreased meiofaunal abundance.The meiofauna group compositions had been analyzed. The results showed that they did change seasonally and spatially. Nematoda was the most dominant group, and then, Copepoda and Polychaeta was another two main component groups in each season and sampling location. Beside these three meiofauna groups, Ostracoda, Cnidaria, Cumacea, Amphipoda, Kinorhyncha, Tardigrada, Turbellaria, and Bivalvia were found. By the comparison of meiofauna compositions among three bathing beaches, the composition trends were similar to each other. The vertical distributions of the meiofauna were similar to each other seasonally and spatially, most meiofauna groups with large percentage were found in （0-4） m layers, the abundance decreased with the increasing of the sampling depths. In winter season of the No.1 and 2 bathing beaches, the meiofauna abundance in （0-4） cm layers dramatically decreased. This indicated that the cold temperature has the direct effect on meiofauna, and pushes the meiofauna migrate downwards to maintain heat. However, the phenomenon did not occur in the winter of the No.3 bathing beach. And, the vertical distribution in the outfall zone of No.1 bathing beach was absolutely different to other studies, the larger meiofauna abundances always were found from deeper depths. This maybe caused by human-disturbance （i.e., daily run-off from outfall）: the strong run-off movement reduced the surface salinity; and force the meiofauna migrate downwards.The last section of the thesis was a summary about the organic-enrichment study based on both the laboratory microcosm experiment and corresponding field study. The key hypothesis of this study is to examine whether the meiofaunal abundance would be affected by the organic enrichment, and whether and how the abundance would be higher in high-organic enrichment levels other than in low-organic enrichment levels. To examine this, a 21-days laboratory microcosms experiment was set up. N/C ratios were investigated as well. The organic content of the sediments is a decisive factor and plays a key role in meiofaunal density and diversity. Among three different organic content levels （high-organic level, low-organic level and control/reference level）, both of meiofauna and nematode abundance was significantly different. However, the abundance was highest in non-organic matter added （control/reference） treatments; comparing with other groups, i.e., the low-organic and high-organic matter addition treatment results, a fair decrease in the total meiofaunal and nematode abundances was obtained and the number of taxa was greatly reduced. However, only the decrease in low-organic matter groups was statistically different with non-organic matter groups （control groups）. Overall, the results of the thesis showed that not only do meiofauna abundances vary seasonally, but also does the group composition. No.1, 2 and 3 bathing beaches were all human-disturbed areas, and No.1 bathing beach was affected by the human disturbance mostly in tourism seasons, nematode was the most dominant meiofauna group and least affected.Which abiotic and/or biotic factors control meiofauna communities most is still not very clear because of the lack of sufficient data to come up with an answer. But, by the evidence from this thesis, the spatial and temporal change of meiofaunal abundance was supposed to be controlled by environmental factors of Chl-α, salinity and temperature mostly, and could be affected by human disturbance.更多还原