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11.
近岸海域的生态系统管理,要求对海洋健康进行综合的评估以及对人工调控进行科学的指导,进而促进可持续发展。本文构建了定量化方法,用于评估当前的和近期的基于生态系统服务的海洋健康。以莱州湾为例的研究结果表明,当前的海洋健康指数分值为0.7856(总分为1.0);通过对负面压力进行不同强度的人工调控,得到近期海洋健康预计的变化范围为0.5551到0.8041。具体地说,本文评估得到当前的海洋健康主要表现为文化服务和供给服务基本优秀,而支持服务和调节服务不够良好。若不对持续增长的压力采取有效的调控措施,该近岸海域生态系统会在近期丧失部分支持服务和调节服务;若负面压力被完全控制,该近岸海域生态系统服务的分类等级会得到小幅提升。另外,应进一步加强对生态系统服务尤其是文化服务和调节服务的宣传教育。本文的分析过程和量化结果,为进一步指导人工调控提供了灵活的工具,有助于海岸带区域的生态系统管理。  相似文献   
12.
The Water Framework and Habitats Directives require the evaluation of both the conservation and ecological status of macroalgae communities at water body or habitat level. However, assessments of macroalgal communities are highly time-consuming, both in terms of sampling effort and laboratory processing. These constraints have brought about their oversight in many marine monitoring programs, especially in subtidal environments. By using data from intertidal and subtidal macroalgae assemblages of Mouro Island (North coast of Spain) we wanted to identify possible cost-effective methods for monitoring this biological indicator, based on both high taxa levels and use of representative taxa. Multivariate analyses were applied using different data transformations. The results show that macroalgal communities are robust to aggregation to genus or even family level. Moreover, the outcomes show that transformation types introduce higher variation in the multivariate pattern of samples than the taxonomic level to which organisms are identified. Also, the study supports the use of representative taxa as a surrogate to overall community structure. Therefore, we conclude that a rapid-assessment by means of field evaluations, based on coverage of representative taxa, is a reliable alternative for the assessment of macroalgae status. In addition this procedure allows evaluation at a broader spatial scale (water body or habitat level) than traditional quantitative sampling procedure does.  相似文献   
13.
Nine species of Prionospio complex are recorded from China’s waters, including one new species and six newly recorded species. Prionospio (Prionospio) pacifica sp. nov., is characterized by having first and forth pairs of branchiae pinnate, second and third pairs of apinnate, ventral crest on Setiger 9 and dorsal crests on Setigers 10—25. Apoprionospio kirrae (Wilson, 1990), Prionospio (Aquilaspio) convexa Imajima, 1990, Prionospio (Minuspio) multibranchiata Berkeley, 1927, Prionospio (Prionospio) bocki Sderstrm, 1920, Prionospio (Prionospio) dubia Maciolek, 1985 and Prionospio (Prionospio) paradisea Imajima, 1990 are recorded for the first time from China’s waters.  相似文献   
14.
The growth dynamics of two co‐occurring seagrass species, Zostera marina and Halophila nipponica, were examined on the southern coast of the Korean peninsula. Zostera marina is a native dominant seagrass species in Korean coastal waters, whereas H. nipponica is a non‐native tropical and subtropical species that has extended its distributional range to the temperate coastal areas of Korea. To examine the differences in the growth dynamics of H. nipponica and Z marina, their morphology, density, productivity and biomass, as well as local environmental conditions, were monitored monthly from January 2008 to July 2009. Underwater irradiance at the study site was the highest in April 2009 and the lowest in January 2008. Water temperature ranged from 10.4°C in January 2009 to 24.8°C in September 2008. Significant differences in growth dynamics were observed between the species, due to the effect of water temperature at the study site. Density and areal productivity were the highest in April 2008 and June 2008, respectively, for Z marina but the highest in July 2008 for H. nipponica. Leaf size, shoot height and shoot weight were the highest in July 2008 for Z marina but the highest in August 2008 or September 2008 for H. nipponica. The productivity of both species was strongly correlated with water temperature at the study site. However, the productivity of these species was not strongly correlated with underwater irradiance or the nutrient availability of either the water column or sediment pore water. Zostera marina exhibited the ecological characteristics of a temperate seagrass, whereas H. nipponica retained the features of a subtropical/tropical seagrass, even after adapting to the temperate coastal waters of Korea.  相似文献   
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16.
Understanding suspended particulate matter (SPM) dynamics in coastal waters is crucial to assess changes in coastal sediment budgets and biogeochemical fluxes. SPM dynamics are subject to various physical and biological factors and processes such as, e.g. tidal currents and aggregation which can be enhanced by extracellular polymeric substances (EPS) that are produced by algae and bacteria. It is still unclear how the different factors and processes interact and together determine SPM dynamics. To unravel the interacting processes and factors, we propose a new distribution-based modeling approach. Based on the derivation of explicit equations for size distribution characteristics of SPM such as the average radius, we derived a model of reduced complexity characterized by low initialization and parameterization effort as well as low computational cost. The proposed 0D model includes the processes of aggregation and fragmentation due to shear, aggregation due to differential settling, deposition, resuspension and tidal exchange, and describes the evolution of the SPM concentration in the water column linked by the settling velocity to the change of the mass average radius of the aggregate distribution. A systematic parameter variation for critical bottom shear stress of erosion, the size of resuspended aggregates, the fractal dimension, the collision efficiency, and the aggregate strength has been performed and compared to observations in the back-barrier basin of Spiekeroog Island in the German Wadden Sea. This analysis confirms the hypothesis that in winter biological influences on SPM dynamics are smaller compared to summer. This is mainly reflected by a significant shift in the various parameters. We hence conclude that biological control mechanisms have a much more quantitative relevance for SPM dynamics than currently represented by state-of-the-art SPM transport models.  相似文献   
17.
The colonization features of periphytic diatoms were studied in coastal waters of the Yellow Sea, northern China from May to June 2010, using glass slides as an artificial substratum. Samples were collected at a time interval of 1, 3, 7, 10, 14, 21 and 28 d from two depths of 1 and 3 m. The dynamics of diatom colonization process had a similar pattern in community structure and fitted the logistic model in growth curve at both depths. The maximum abundance and the time for reaching 50% maximum abundance (10 d) showed no significant differences (P〉0.05) between two depths 1 and 3 m. Although the diatom communities repre- sented similar taxonomic composition, they differed in the temporal pattern of structural parameters and in succession dynamics of dominant species between the two layers. The species richness showed significantly higher values during the colonization period more than 14 d, while the species diversity and evenness rep- resented a higher variability with significantly different values (P〈0.05) at a depth of 1 m than at a deeper layer. The results suggest that the diatom colonization follows the logistic model growth curve and differs in colonization features between different depths in the coastal waters, and that the sampling strategy at i m is more effective to detect the ecological features for bioassessment in marine ecosystems.  相似文献   
18.
分别于2012年9月、2013年1、6月,对九龙江两大支流北溪、西溪及河口区开展了3个航次的营养盐监测.研究结果表明,河口区表层水体溶解无机氮(DIN)、总磷(TP)和活性磷酸盐(PO4-P)质量浓度范围分别为0.13-17.35、0.14-1.00和0.00-0.38 mg/dm3,受上游输入和海水稀释作用,营养盐浓度由淡水端至海水端逐渐降低.北溪表层水体的DIN、TP和活性磷酸盐质量浓度范围分别为1.99-24.92、0.12-1.47和0.04-0.68 mg/dm3,受龙岩地区工农业生产及城市进程影响,由上游至下游逐渐降低.西溪表层水体的DIN、TP和活性磷酸盐质量浓度范围分别为2.74-20.61、0.14-0.92和0.02-0.37 mg/dm3,受上游农业生产和下游漳州地区人类活动影响,上下游的DIN质量浓度较高.此外,九龙江沿岸的人类活动可能影响了该地区水体中的溶解无机氮形态组成:北溪和西溪上游的NH4-N和NO3-N占比分别较高.水期分析表明,2013年1月的DIN浓度显著高于其他水期,而不同区域TP和活性磷酸盐的水期波动不尽相同.营养盐结构分析表明,九龙江总体处于磷限制状态,但在河口及北溪部分站位,CDIN/CPO4-P比值已达到适合浮游生物生长繁殖的水平.潜在富营养化程度评价表明,九龙江河口多数站位均处于N或P限制的富营养化级别,但由于N、P营养盐的绝对浓度较高,具有水华暴发的潜在风险.  相似文献   
19.
大陆岛入海沉积物通量(Qs)信息对于精确解译大陆架沉积记录的研究是个重要补充。针对如何估算大陆岛Qs的科学问题,本文以中国东南部海域的8 227个大陆岛为例,提出了一种基于邻近大陆中小型河流Qs的经验公式计算大陆岛Qs的解决方案。该方案在实施时需设置两个假定,即大陆岛的Qs法则遵循邻近大陆中小河流的Qs法则和可将1个大陆岛当作1个河流流域计算其Qs。结果表明:(1)经验公式计算的大陆岛Qs为其最小估计值;如考虑大陆岛流域的具体情况,实际的Qs值会稍微增加,但其增幅不超过n0.13n为流域数量);(2)经验公式能获取大陆岛Qs的大致数量级信息;大陆岛的总面积为4 418.49 km2,对应Qs的数量级为106 t/a,与邻近大陆中型河流入海通量的数量级相当;(3)在大河河口湾充填阶段完成以前,大陆岛沉积物是内陆架泥质沉积体的主要物源之一。因此,大陆岛入海沉积物会对大陆架沉积体系的形成和演化造成一定程度的影响,需引起研究人员的高度重视。  相似文献   
20.
A new methodology to classify European North-East Atlantic transitional waters into ecological types has been developed based on the most important hydrological and morphological features that are likely to determine the ecology of aquatic systems in transitional waters. Hydrological indicators help identifying if a transitional water area is dominated by fresh or sea water and/or by intertidal or subtidal areas, while morphological indicators allow an estimation of the complexity of the transitional water and the diversity of the habitats involved. Twelve transitional waters of the southern Bay of Biscay were classified using this methodology and the five hydro-morphological types obtained were validated with benthic macro-invertebrate data. Transitional waters with a complex morphology showed the highest values of species diversity, while those with a smaller tidal influence showed lower species diversity. The ‘Scrobicularia’ and ‘Abra’ assemblages, previously identified in the study area, were found to be related to different types of transitional waters. The ‘Abra’ assemblage only appeared in estuaries with a complex morphology and dominated by tidal influences, while the ‘Scrobicularia’ assemblage was detected in all the transitional waters except for a single coastal lagoon. This classification of transitional waters may therefore be useful to establish the biological reference conditions needed for European Directives.  相似文献   
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