“海中游”七防

在炎热的夏季，许多人都喜欢到大海中游泳，“海中游”既能健身又可避暑，还可与大自然亲密接触，是一举多得的选择。然而，大海浩瀚无垠，变化莫测，条件复杂，存在一些不确定因素，如果处置不当，容易发生意外。所以，在“海中游”前应对可能出现的意外情况，准备相应对策，以确保安全。

Phaeocystis globosa Scherffel,a harmful microalga,and its production of dimethylsulfoniopropionate

The production of dimethylsulfoniopropionate （DMSP） and its cleavage products （DMS） are well studied in phytoplankton worldwide. However, less is known about their sources, distributions, and impacts in the coast of China. We examined the production of DMSP and DMS in Phaeocvstis globosa Scherffel and other benthic macroalgae from the South China coast in relation to environmental conditions. P. globosa was a harmful marine microalgal species and its bloom took place in the eutrophic waters along the South China Sea frequently. It also produced high content of DMSP at different growth stages, with the highest concentration usually observed in the stationary period. Moreover, the production of DMSP in P. globosa was significantly affected by salinity and temperature with the highest contents associated with high salinity （e.g. 40） and low temperature （e.g. 20℃）. In field benthic macroalgae, there was also a marked difference in the DMSP of various species or different samples of the same species. Chlorophyll a contents were also determined for each macroalgal species. The highest chlorophyll a （238.7 ng/g fresh weight） was recorded in Chlorophyta Ulva lactuca at Guishan Island （Zhuhai）, while the lowest value （1.5 ng/g fresh weight） was found in Rhodophyta Gracilaria tenuistipitata in Zhanjiang. Further correlation analysis indicated that there was no significant relationship between the content of DMSP and chl-a in macroalgae samples （P〉 0.05）. All the results suggested that the production of DMSP in marine algae was not only species- and stage-related, but also greatly affected by various environmental factors.

Expectation and satisfaction of rural tourism:a case study of Hainan,China

This study uses the rural tourist motivation scale to measure the motivations, expectations, and satisfaction of nearly 200 rural tourists in five areas of Hainan, China by importance-Performance Analysis (IPA) and factor analysis. The results show that the main motivation for participating in rural tourism is to be close to nature, improve family rela-tionship and relaxation. Tourists are highly satisfied with the landscape and pastoral views as well as the friendliness of the local people and hotels. The results also show that the sample people most care about easy parking and reasonable prices, and they expect ethnic festivals and farm life experiences. Besides the environment, facilities, recreational activities and psychological experience of rural tourism, the overall satisfaction is high. The results of this study can be used by local government leaders as well as the tourism industry to devise ways to promote and improve rural tourism.

Biomarker evidence for paleoenvironmental changes in the southern Yellow Sea over the last 8200 years

Previous studies have indicated that the Yellow Sea underwent significant environmental changes during the Holocene, but many questions remain concerning the timing of the establishment of the modern circulation system, which would have major implications for the Yellow Sea ecosystem and carbon cycle. In this study, marine and terrestrial biomarkers were analyzed in Core YE-2 from a muddy area in the southern Yellow Sea to reconstruct Holocene environmental and phytoplankton community change. The content of three individual marine phytoplankton biomarkers (alkenones, brassicasterol and dinosterol) all display a similar trend, and their total contents during the early Holocene (362 ng/g) were lower than those during the mid-late Holocene (991 ng/g). On the other hand, the contents of terrestrial biomarkers (C27+C29+C31n-alkanes) during the early Holocene (1 661 ng/g) were about three times higher than those during the mid-late Holocene (499 ng/g). Our biomarker results suggest that the modern circulation system of the Yellow Sea was established by 5-6 ka, and resulted in higher marine productivity and lower terrestrial organic matter inputs. Biomarker ratios were used to estimate shifts in phytoplankton community structure in response to mid-Holocene (5-6 ka) environmental changes in the Yellow Sea, revealing a transition from a dinoflagellate-diatom dominant community structure during the early Holocene to a coccolithophore-dominant community structure during the mid-late Holocene.

Temporal and spatial variation of fish assemblages in Dianshan Lake, Shanghai, China

Using multi-mesh gillnets and trawls, the fish communities in Dianshan Lake at 6 stations from Oct. 2009 to Jul. 2010 were investigated seasonally to reveal the biodiversity and its spatial and temporal distribution patterns. The long-term changes in their structural characteristics were then analyzed to identify the main infl uencing factors and several measures for lake restoration were put forward. Thirty six species, belonging to 9 family and 30 genera, were collected, amongst which, the order Cypriniformes accounted for 61.1% of the total species number. In terms of importance value, Cypriniformes was the predominant group, Coilia nasus the dominant species, while Cyprinus carpio and Rhinogobius giurinus were the subdominant taxa. The community types did not differ among stations, but between seasons. There were no significant differences between seasons and among stations in species diversity, but richness differed both spatially and seasonally. Along with the process of eutrophication and the drastic reduction of the area colonized by macrophytes from 1959 to 2009–2010, the fish diversity declined markedly, and species numbers of herbivores and piscivores declined proportionately more than those of invertivores, omnivores, and planktivores. The decline of potamophilus and river-lake migratory fish was more marked than those of sedentary, river-sea migratory, and estuarine fishes. Eutrophication concomitant with sharp reduction of macrophyte area and overfishing may be the main reasons for the decline in fish diversity in Dianshan Lake.

Research on Tourism Competitiveness of Chinese Island Counties:Based on Factor and Cluster Analysis

From the perspective of tourism competitiveness,the paper takes 12 island counties of China as the research object,and applies the method of factor analysis to study their competitiveness.The result shows that Putuo and Dinghai are more competitive while Pingtan and Nan'ao are less competitive.Finally,the 12 island counties are divided into four styles:first-class competitive county (Putuo),seond-class competitive counties (Dinghai,Yuhuan),third-class competitive counties (Chongming,Daishan,Changdao,Changhai and Shengsi),fourth-class competitive counties (Dongshan,Dongtou,Pingtan and Nan'ao) by cluster analysis.The classification of island counties is to clear their relative position,then to promote their development.

The Impact of Atmospheric Deposition of Cadmium on Dominant Algal Species in the East China Sea

Cadmium(Cd) mainly derived from anthropogenic emissions can be transported through atmospheric pathway to marine ecosystem,affecting the phytoplankton community and primary productivity.In this study,we identified the toxicity threshold of Cd for phytoplankton under seawater conditions of the coastal East China Sea(ECS) through both laboratory and in situ mesocosm incubation experiments.The mesocosm experiment showed that Cd in low concentration(0.003 μg per μg chl a) was conducive to the growth of natural community and increased chl a productivity.In high concentration(0.03 μg per μg chl a) Cd acted as an inhibiting factor which decreased the total chl a productivity.The diatom community was found to be more sensitive to Cd toxicity than dinoflagellate,as the low concentration Cd showed toxicity to diatom but enhanced dinoflagellate growth.We noticed that the soluble Cd estimated from atmosphere deposition to the coastal ECS was below the toxicity threshold and the Cd deposition might promote phytoplankton growth in this region.In our laboratory experiments,adding Cd,similar to aerosol deposition,stimulated the growth of both dominant algal species Prorocentrum donghaiense Lu(dinoflagellate) and Skeletonema costatum(diatom).Adding Cd on a higher level inhibited the growth of both the species,but Skeletonema costatum seemed obviously more sensitive to toxicity.This indicates the potential impact of atmospheric deposition Cd on phytoplankton community succession in the ECS.

Photodegradation of Methylene Blue in Natural Seawater

This paper reports the photochemical degradation of Methylene Blue(MB)in natural seawater(NSW).The photode-gradation reaction conformed to the first-order reaction kinetics with the rate constant 0.0158 min-1.MB was photochemically de-gradated faster under high-pressure mercury lamp(HPML)than under sunlight.When MB was in lower concentrations,salinitycould inhibit the photoreaction whereas MB in higher concentration,salinity could accelerate the photoreaction.Humid acid couldalso inhibit the photoreactions.Toxicity tests with marine phytoplankton Skeletonema costatum(Sk)and Heterosigma akashiwo Hada(Ha)showed decreased acute toxicity after photodegradation.

Phytoplankton pigment patterns and community composition in the northern South China Sea during winter

Phytoplankton pigment patterns and community composition were investigated in the northern South China Sea using high-performance liquid chromatography and the CHEMTAX software from February 11 to 23, 2009. We recognized four different vertical distribution patterns of pigments: chlorophyll a (Chl a)-like type, divinyl chlorophyll a (DV Chl a) type, even distribution type, and surface type. The average value of ratios of accessory photo-protective pigments (APP) to accessory photo-synthetic pigments was 0.89±0.63 in the upper 50 m and 0.16±0.06 below 50 m depth. With increasing depth, APP decreased and photo-synthetically active radiation was attenuated. There was an obvious succession in the phytoplankton community from inshore to the open sea. Diatoms were dominant in the inshore region, while pelagophytes, Prochlorococcus, cyanobacteria and prymnesiophytes were dominant in the open sea. The vertical distribution of phytoplankton also differed greatly from inshore to the open sea. In the coastal and shelf region, diatoms were important components in the whole water column. Cyanobacteria also had a high abundance at the Subsurface Chlorophyll a Maxima (SCM) in the shelf region. In the slope and open sea, Prochlorococcus and cyanobacteria were important groups above the SCM, while pelagophytes dominated below the SCM.

Variation of Bacteria Biomass and its Possible Controlling Factors in the East China Sea

Two surveys were performed for determining bacteria biomass (BB), temperature, salinity, chlorophyll a (chl-a) and nutrient concentrations at 11 stations with three sampling depths in the high-incidence regions of red tide in the East China Sea (ECS) in the spring of 2006. Temperature and salinity increased from nearshore to offshore region and from high latitude to low latitude in the two cruises of 2006. BB were between 0.3 5.2 mgC m-3 (about 2.1 mgC m-3 on average) and 0.2 6.0 mgC m-3 (about 2.7 mgC m-3 on average) respectively in the two cruises. BB in the surface layer decreased from the Changjiang River estuary to high sea and from low latitude to high latitude. The results showed that bacterial growth was regulated by temperature, primary production and inorganic nutrient concentrations depending on different hydrographic conditions. In the surface and middle layers where the primary production can supply enough organic substrate, temperature was the main factor to control bacteria biomass. BB showed a good correlation between the surface and middle layers in both cruises. The distribution of nutrients during both cruises showed a similar decreasing trend from nearshore region and high latitude to offshore region and low latitude. High BB values were mainly recorded from samples in the middle layer where chl-a concentrations were also high, indicating primary production being strongly correlated with temperature over the ECS shelf. In the offshore area, phosphate and silicate became limiting factors for phytoplankton growth with indirect influence on BB. Bacteria played an important role in nitrogen regeneration process turning organic nitrogen to inorganic forms such as NH4+. The increasing ratio of NH4+/DIN could be a proof of that.

Study on the Characteristics and Problems of Water Tourism Development in China

Water tourism is known as the ＂water mobile resort＂,＂an important economic growth pole of the waterfront city＂, which mainly includes boat cruises, yacht water sightseeing, leisure, hydrophilic service and derivative related industry services, etc. Because of the sightseeing way, it is increasingly subject to the attention of many domestic waterfront city. This paper mainly analyzes the characteristics of the development of water tourism in China and the problems in the development process.

A study on the tourism practitioners' perception of tourism impact:a case study of Hainan,China

This study examines the urban population of tourism practitioners' perceptions of economic, environmental, and social impacts on cultural, convention, and sport tourism may have in Haikou and Sanya, Hainan, China. The study uses a modif ied Urban Tourism Impact (UTI) to examine economic, environmental, and social perceived impacts. Analysis of the data includes testing three models of structural relationships between tourism impacts and support for development in each of the tourism market sub-divisions through a confirmatory factor analysis. The results of this study show that the positive economic impacts consistently exert influence on predicting support for tourism development in all three models. However, the social impacts play a greater explanatory role with all three market segment, the negative environmental impacts play a role in determining support for sport tourism only. Differences have been found with those with a higher education level in predicting support for cultural tourism, but not convention or sport tourism.

Sea surface temperature evolution in the western South China Sea since MIS 12 as evidenced by planktonic foraminiferal assemblages and Globigerinoides ruber Mg/Ca ratio

Based on the detailed planktonic foraminifera faunal count and Globigerinoides ruber Mg/Ca ratio analysis of Core MD05-2901,we reconstructed the longest Mg/Ca sea surface temperature(SST) sequence of the upwelling area off Vietnam in the western South China Sea(SCS).Ocean environment,especially the SST variation,over the last 450 ka is discussed in this study.SST variation has typical glacial/interglacial alternations from 23.03°C to 29.93°C with a glacial/interglacial difference of 4.8°C on average.SST during the interglacial periods fluctuates significantly,up to 5.6°C,which is larger than the average glacial/interglacial difference.SST variation during the glacial periods is much smaller.Spectrum analysis shows that SST change dominates on the typical Milankovitch cycles,such as 112,40.7 and 23.6 ka.Evident leading of SST variation against the δ 18 O can be observed during the Terminations 1,4,and 5,which is confirmed by their cross-spectrum analysis on these cycles.MD05-2901 is the first core in the South China Sea that has multi-SST records,such as SST Mg/Ca,k' 37 U-SST and planktonic foraminiferal fauna-based SST.SSTs from different methods can be correlated with each other in glacial/interglacial time scale,whereas SST Mg/Ca records abrupt climate change events more clearly.SST Mg/Ca at MD05-2901 since MIS 5 is 0.6°C lower than that of the southern SCS on average,but equivalent to or even 2°C lower than that of the northern SCS during some interglacial period.The SST character of MD05-2901 reflects less influence of latitude,but an important role of the regional upwelling driven by the eastern Asian summer monsoon,and suggests a stronger upwelling during the interglacial periods in the western SCS.

Modulation of the urban heat island by the tourism during the Chinese New Year holiday: a case study in Sanya City,Hainan Province of China

The urban heat island （UHI） represents one of the most significant human impacts on the earth system. In recent decades, the number of the tourists has a remarkable increase in China and also other regions of the globe. However, it is still unclear whether or to what extent the tourism can affect the UHI. Here, we investigate the role of the tourism for the UHI during the Chinese New Year （CNY） holiday based on a case study in tropical Sanya City, which attracts many tourists for celebrating the CNY and enjoying the warm climate during the holiday. We find that the UHI effects expressed as daily mean （ATmean）, maximum （ATmax）, and minimum （ATmin） surface air temperature differences between urban and nearby nonurban stations averaged over the period of 1995-2004 during the CNY week were 0.48 ℃ （39 %）, 0.66 ℃ （61%）, and 0.42 ℃ （26 %） higher than those averaged over the background period （8 weeks including 4 weeks before and 4 weeks after the CNY week）, respectively. These changes are all significant at the 99 % confidence level. Our findings highlight previously unidentified impact of the tourism on the UHI based on a case study in Sanya City, Hainan Province of China.

Hydrographic field investigations in the Northern South China Sea by open cruises during 2004-2013

In the past 10 years （2004-2013）, annual open cruise during late summer provided new opportunities for comprehensive studies in the Northern South China Sea （NSCS）. The 10-year field investigation program was carried out by the South China Sea Institute of Oceanology, Chinese Academy of Sciences （SCSIO, CAS）. Measurements inclu- ded water mass property, ocean circulation, atmospheric structure, and chemical and biological elements. The observation data collected during these open cruises have been intensively used in the studies of marine oceanographic, meteorological, chemical, and biological processes in the NSCS. In this study, comprehensive assessment of data application in oceanographic and meteorological studies is provided： （1） the property and variability of water masses in different layers; （2） the distribution of main currents and three-dimensional structure of mesoscale eddies; and （3） atmospheric structure and its feedback to the ocean. With the continuance of open cruises, it is feasible to construct high- quality, gridded climatological marine meteorological datasets in the NSCS in the near future.

Carbon isotopic composition of Early Triassic marine carbonates, Eastern Sichuan Basin, China

As the interval following the biggest Phanerozoic mass extinction at the end of Permian, the Early Triassic is characterized by an immature, poorly functioned ecosystem.The effects of these extreme environmental conditions can be mirrored by the changes in the δ13C record of marine carbonates.However, the details about the carbon isotopic composition and evolution of the Early Triassic seawater remain poorly understood.A dataset of new δ13C and δ18O values as well as selected major and trace element data (including concentrations of CaO, MgO, Mn, and Sr) was obtained from 113 marine carbonate samples collected in Eastern Sichuan Basin.The isotopic and elemental data are used to evaluate effects of thermochemical sulfate reduction on δ13C.The δ13C values of a few samples affected by thermochemical sulfate reduction were corrected.By combining carbonate δ13C results in our investigated sections, we constructed a composite curve of the Lower Triassic.The results reveal a δ13C anomaly of carbonate rocks throughout the Early Triassic, accompanied by some rapid jumps and falls, such as those from approximately -2‰ to the extremely high value of 8‰ within a period of about 5 Ma.The Early Triassic δ13C profile derived from Eastern Sichuan Basin shows a close correspondence with Guandao section in Guizhou Province, whereas it yields an excursion pattern differing from Chaohu section in Anhui Province of the Lower Yangtze region (with the δ13C value from the minimum around -6‰ to the maximum near 4‰).The higher δ13C values and the positive carbon isotope excursions in the Lower Triassic from Eastern Sichuan Basin were most likely a consequence of the principal environmental change that may include: (1) the barren land surface due to the absence of vegetation, (2) the loss of diverse marine invertebrate groups and marine carbonates, (3) the thriving of bacteria, algae and methanogenus in ocean ecosystems, and (4) the local effect of the repositories of isotopically light carbon occurred in the form of methane hydrates.This process ended at the Early-Middle Triassic boundary, which indicates that the biotic recovery started at the end of the Lower Triassic.The terrestrial vegetation and marine invertebrates, as the regulators for carbon cycle, are irreplaceable and demand strong protections.