Marine Biodiversity Under Global Climate Change
To explore the characteristics of a macrozoobenthic community in the sea adjacent to the Yangtze River estuary during the wet season, macrozoobenthic samples were collected during June, August, and October, 2012, and data were analyzed using statistical methods including Two-Way ANOVA, Cluster analysis, Non-metric Multidimensional Scaling (NMDS), and Abundance-Biomass Comparison Curves (ABC Curves). A total of 181 macrozoobenthic species were recorded, with 82 species of Polychaeta, 46 Crustacea, 31 Mollusca, 11 Echinodermata and 11 species belonging to other groups. The abundance, biomass, Margalef’s richness index (d), Shannon-Wiener index (H'), and Pielou index (J') did not show any significant temporal or spatial differences except that J' in the offshore area was significantly higher than that found in the inshore area. Three to four macrozoobenthic assemblages were identified using the 20% similarity level and a low similarity level among stations was also observed. ABC curves revealed that the macrozoobenthic community in the offshore area was less disturbed than that in the inshore area. As a result of the continuous impact of anthropogenic activities, the macrozoobenthic community was severely disturbed and unevenly distributed in the sea adjacent to the Yangtze River estuary.
Coccolithophores are important components of the phytoplankton community that play a unique role in the global ocean biogeochemical cycle though carbon fixation and calcium carbonate production. In addition, coccolithophores are good indicators of climate change as they have indicative organic and inorganic remnants in sediments. Emiliania huxleyi is the most typical representative of coccolithophores. Classification of coccolithophores is mainly based on coccoliths, which have very fine and complex structures and are easily destroyed during the sample collection process. It becomes a technical problem to identify coccolithophores. In this study, atomic force microscopy (AFM) was employed to observe coccoliths of Emiliania huxleyi with the purpose of establishing an AFM sample preparation method for coccolithophores. Centrifugation was found to be an appropriate method to deal with the AFM samples compared with filtration. An optimized protocol was established: cells are centrifuged at 3,000-4,000 rpm, 20℃, over 5 minutes, a precipitate is suspended in 0.05 M NH4HCO3 solution, and then a droplet of solution containing suspended coccoliths is pipetted onto a glass attached to the sample holder. High resolution images had been captured under the contact mode of AFM in air conditioning with a scan range of 50 µm and frequency of 1 Hz. The method is applicable to analyze the morphological features of coccoliths under various environmental parameters or gradients in the laboratory and is also suitable for coccolithophore bloom detection.
Jiaozhou Bay is a semi-enclosed bay at the southern shore of Shandong Peninsula and has abundant macrobenthic species. In present study, the seasonal variation of the macrobenthic community in this bay was analyzed based on data collected from four cruises in February (winter), May (spring), August (summer) and November (autumn) of 2014. A total of 199 macrobenthic species were identified, of which, 79 species were Polychaeta, 47 were Crustacea, 40 were Mollusca, 17 were Echinodermata, and the remaining 16 species belong to other animal groups. The composition of dominant species seasonally varied, however, most of them were species belong to Polychaeta. The average abundance of the macrobenthos from the four cruises was 209.85 ind./m2, with the highest abundance found in the autumn cruise and the lowest in the spring cruise. The average biomass from the four cruises was 79.22 g/m2, with the highest biomass found during the summer cruise and the lowest found during the spring cruise. The Shannon-Wiener index (H') of the macrobenthic community varied from 2.16 to 2.86, the species richness index (D) varied from 2.79 to 3.72 and the species evenness index (J) varied from 0.58 to 0.82. The Bray-Curtis similarity cluster analysis and NMDS ordination analyses indicated that the similarity among macrobenthic community groups was low and the distribution pattern of microbenthic animal groups showed seasonal characteristics. In recent years, with the rapid economic development of coastal zones and the continuous impact of human activities, the stability of the benthonic community in Jiaozhou Bay is threatened, therefore, long-term monitoring is recommended and effective comprehensive management measures need to be explored to result in the healthy and sustainable development of the marine ecosystem in Jiaozhou Bay.
Eighteen years of monitoring data at four sections along the coastline of Taisi Township, Yunlin County, between 1993 and 2010 were used to study the effects of power plant on plankton. Sampling was conducted at depths of 10 m and 20 m in each section. Among the four seasons, the fourth quarter (October to December) had the lowest average abundance of plankton over the years. However, the peak abundance of different types of plankton occurred in different seasons. Zooplankton had the highest abundance during the first and second seasons (January to June) while phytoplankton, shrimp larvae and crab larvae had the greatest abundance in the 2nd quarter (April to June) and the peak in fish egg and fish larvae occurred from the 1st to the 3rd quarter (January to September). Cumulative data from 18 years shows that the pH of SEC5 often dipped below 7.8 since the 3rd quarter of 2000. pH value lower than 7.8 were frequently measured in the stations of section 5. Each time the pH value is under 7.8, the quantities of zooplankton (75±69 ind./m3), phytoplankton ((1.60±2.28)×103 cell/L), shrimp larvae (2.4±5.8 ind./m3), crab larvae (1.9±5.0 ind./m3), fish egg (0.88±1.10 ind./m3), and fish larvae (0.16±0.32 ind./m3) showed significant low values (only the half of the total average). Accordingly, we strongly suggest that the warm water effluents discharging from a power plant should maintain the pH above 7.8 in the coastal waters to reduce the negative impact on the marine zooplankton biodiversity and abundance.
Conservation and sustainable use of marine and coastal biodiversity is an important part in the Conservation on Biological Diversity (CBD). By reviewing the course of negotiation, this paper finds that focal issues include: (1) Actions to address the impacts caused by human activities and global change on marine and costal biodiversity; (2) Tools for the conservation and sustainable use of marine and coastal biodiversity resources; and (3) Marine protected areas and Ecologically or Biologically Significant Marine Areas (EBSAs). These negotiations may have impacts on marine biodiversity conservation, and the process of establishing a network of global marine protected areas and international marine biodiversity conservation, as well as socioeconomic development in maritime countries. In the future, China should accelerate research on marine related science and technology, become actively involved in the course of negotiations, and publicize achievements in the implementation of the Convention.
The species richness and abundance of tintinnids in the surface waters at 23 stations located in southeast of Hawaii were investigated between 14 August and 18 September 2013. A total of 36 species in 22 genera were identified. All tintinnid species had hyaline loricae. The species richness of tintinnids in each station ranged from 15 to 21. Tintinnid abundance and biomass ranged from 4,730 to 23,693 ind./m3, and from 9.60 to 88.61 μg C/m3, respectively. The top four dominant species were Ascampbelliella armilla, Steenstrupiella steenstrupii, Eutintinnus tenuis and S. gracilis. These top four dominant species were in different lorica oral diameter (LOD) size-classes.
As a habitat-forming species, the red alga Gracilaria vermiculophylla has been noted to play an essential role in shaping coastal marine communities and maintaining intertidal ecosystems along Chinese coasts. However, few studies have been conducted that analyze the genetic structure of the population and the distribution patterns of genetic variation. In this study, we compiled partial mitochondrial DNA cytochrome c oxidase subunit I gene (cox1) of 19 G. vermiculophylla populations (461 individuals) and performed phylogenetic analysis and population genetic surveys. A total of 461 mt-DNA cox1 sequences were obtained and edited into 641 bp, which contained 21 polymorphic sites and yielded 15 haplotypes. Phylogenetic inferences, haplotype networking, and principal coordinate analysis consistently indicated that G. vermiculophylla populations diverged into two groups: the northern group is comprised of specimens from the Yellow-Bohai Sea and the Shengsi Islands, while the southern group is comprised of specimens from six locations south to Xiamen, Fujian Province. Analysis of the molecular variance and Nei’s genetic distances indicated low genetic differentiation between populations in each group while group-level genetic divergence is comparable to the degree of subspecies differentiation.
Understanding the effect of global climate change (GCC) on earth ecosystems is a key issue worldwide. Compared to terrestrial ecosystems, marine ecosystems are more sensitive to GCC. Stresses that GCC brings to oceans include warming, ocean acidification, changes in currents, sea level rise, and enhancement of ultraviolet radiation, etc. Phytoplankton are the key primary producers in marine ecosystems and very important in the ocean carbon cycle. Distribution patterns, primary productivity, community succession and phenology of phytoplankton can all be affected by GCC. For phytoplankton species distribution, the distribution region of warm-water species is generally extended, which is opposite the trend of cold-water species. Phytoplankton primary productivity is decreased globally, and phytoplankton cell sizes are gradually reduced. Intensity and timing of phytoplankton blooms are stronger and earlier, with a higher frequency of harmful algal blooms. Ocean acidification has been found to greatly affect the metabolisms and biodiversity of marine organisms, especially calcifying species. Enhancement of ultraviolet radiation may inhibit the growth of phytoplankton. Furthermore, El Niño, La Niña and enhanced precipitation will decrease phytoplankton biomass. The changes in phytoplankton growth and distribution will lead to variation of its biodiversity from the gene to ecosystem levels. Phytoplankton eco-physiological studies under GCC driven factors and long-term monitoring are key pathways for understanding the phytoplankton-diversity-ecosystem responses and feedbacks under GCC.
We analyzed and compared the differences in community composition, K-dominance curves and diversity index (H') of zooplankton community structure characteristics inside and outside the Hangzhou Bay in autumn (outside the bay: 122.10°-122.58° E, 30.54°-30.93° N; inside the bay: the east area of north: 121.67°-121.87° E, 30.68°-30.83° N; the east area of south: 121.60°-121.85° E, 29.95°-30.24° N; the west area of north: 121.31°-121.56° E, 30.58°-30.77° N). Results indicated that there were large differences between the community composition of zooplankton outside the bay and those in the three areas inside the bay. The area outside the bay (community I) was composed of nearshore species such as Pseudeuphausia sinica and nearshore low-salinity species such as Centropages dorsispinatus, followed by offshore species. Community II (the eastern area of south Hangzhou Bay) was composed of nearshore low-salinity species such as Labidocera sinilobata, followed by nearshore species. Community III (the eastern area of north Hangzhou Bay) was mixed with nearshore low-salinity species such as Labidocera euchaeta and estuarine brackish-water species such as Tortanus vermiculus. Community IV (the western area of north Hangzhou Bay) was characterized by the dominant species, Tortanus vermiculus of estuarine brackish-water species that had the highest proportion, which was different from the community I. Generally, the community with lower salinity adaptability appeared in the western and northern areas. According to K-dominance curves, the dominance curves of community I and community III were quite gentle. In addition, the initial cumulative dominance of community III was higher than that of community I. Compared with community I, the initial cumulative dominance of community II and community IV were far higher than that of community I. The initial cumulative dominance of community I (outside the bay) was particularly low, which indicated that there were many types of dominant species in community I, and the dominance of single dominant species was lower than those communities inside the bay. Results of variance analysis indicated that there were highly significant differences between the diversity index of zooplankton outside the bay and those in the other three waters inside the bay (P < 0.01). Meanwhile, there were no significant differences between the three communities inside the bay (P > 0.05). This showed that the diversity index of zooplankton outside the bay was higher than those of the communities inside the bay. The influence of different water masses resulted in zooplankton community differences in the inner and outer waters of the bay.
Benthic macrofauna were classified into 5 functional groups, i.e. planktophagous (Pl), phytophagous (Ph), carnivorous (C), omnivorous (O) and detritivorous (D). The biotope difference, seasonal and annual variations of functional group of benthic macrofauna in the intertidal zone of the 14th Yong of Nansha, Guangzhou were analyzed in this study according to the four seasonal data of benthic macrofauna collected in two biotopes (Cyperus malaccensis and Sonneratia caseolaris) in 2007-2008 and 2013-2014. A total of 26 species were recorded in 2007-2008, which was lower than 36 species in 2013-2014. Both in 2007-2008 and 2013-2014, phytophagous group showed the highest value while detritivorous group shared the lowest one in density and biomass. Habitat comparison showed that the abundance index (d), evenness index (J) and diversity index (H') of planktophagous group in Cyperus malaccensis habitat were all higher than those in Sonneratia caseolaris habitat. Annual comparison showed that the abundance index, evenness index and diversity index of planktophagous group in 2013-2014 were all higher than those in 2007 -2008 both in Cyperus malaccensis and Sonneratia caseolaris habitats because the planktophagous such as Gelonia coaxans and Morerlla iridescens and so on were collected in 2013-2014 but they were not found in 2007-2008.
Based on a year round survey conducted in the mangrove swamp of Luoyangjiang Estuary in Fujian from August 2013 to April 2014, macrobenthic diversity, seasonal changes, and the impact of mangrove rehabilitation on the macrobenthic community were analyzed. We recorded a total of 78 species from 7 phyla in the study area and the community was dominated by annelids and arthropods. The gastropod, Assiminea brevicula (Assimineidae), was the most dominant species and was more abundant in mangrove forests than in mudflats. ANOSIM analysis showed that faunal communities were significantly different between mangrove forests and mudflats, with the former characterized by much lower macrobenthic density and biomass. Moreover, some of dominant species, such as Parasesarma plicata and Phascolosoma arcuatum, were only found in mangrove forests. Higher value of macrobenthic density was found in winter and spring, while mean biomass was higher in spring and summer. Significant differences in macrobenthic communites were observed among seasons except between winter and spring. The present study demostrated that, species composition of the mangrove macrobenthos indicated characteristics of a young mangrove plantation and seasonal changes in macrobenthic communities might be due to different breeding seasons of the dominant species. Mangrove vegetation had a noticeable impact on macrobenthic communities, as evidenced by significant difference in macrobenthic communites between the two habitats. Density of macrobenthos in mangrove forests was much lower than that found in 2009, but the sesarminid crab Parasesarma plicata became much abundant. Since mangrove forests and mudflats support different species composition of macrobenthos, planning is needed in mangrove rehabilitation for the protection of habitat diversity and heterogeneity.
Biofouling, the unwanted assemblage of marine organisms colonizing submerged parts of ships and artificial facilities, has a negative impact on human activities related to the sea. The development of fouling communities is closely related to a variety of factors such as temperature, salinity, depth, season, immersion time, geographic location, distance from shore and substratum type. To facilitate systematic analysis and processing of data on marine fouling and clarify the intrinsic relationship between the various elements mentioned above, it is necessary to build a technical platform to integrate scattered and sporadic information and to share this data through a network. By means of internet technology, the ASP.NET framework and MySQL database, the MS Visual Studio 2013 software was used to devise a data management system for marine fouling organisms under the Windows 7 or Windows Server 2008 R2 (recommended) operating system. From the system, data integration, storage and management of fouling organisms are implemented via the network. Query and retrieval of data can be conducted under single or multiple search conditions and the results are exported in several formats according to the user’s requirements. The data management system for marine fouling organisms provides a useful and effective way to help data analysis and decision-making for research, industry and administration.
Zooplankton samples and hydrographic data were collected in the Taiwan Strait (TS) on Fishery Research I cruises during the winter (January) and summer (July) of 2006, to investigate the seasonal and spatial distribution of planktonic pteropods associated with hydrographic conditions. Pteropod abundance and species diversity were higher in summer than in winter, while species richness showed no difference between seasons. The pteropod community structure was similar between seasons, but the abundance ranked differently. Creseis clava, C. acicula, and Limacina trochiformis predominated in summer. Together they accounted for 97% of the total pteropod catches, and, C. clava accounted for 62% of the total catch. Limacina inflata was the most common species in winter, and accounted for 72% of the total catch. The spatial distribution of the abundance of pteropods showed seasonal differences. Higher abundance in the southern TS occurred in winter but in the northern TS occurred in summer. Greater species richness and diversity of pteropods was usually observed in the southern TS during both seasons. Based on our results of hydrographical station groups and their biotic and environmental characteristics, we propose that in the study area the distribution pattern of the pteropod assemblage was closely correlated with the seasonal succession of water masses driven by monsoons.
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