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1.
于2008年3月至2009年1月用电感耦合等离子体质谱法(ICP-MS)对湛江港海水中的铜(Cu)、锌(Zn)、铅(Pb)、镉(Cd)进行调查。分析结果表明:2008年湛江港湾海水中Cu、Zn、Pb、Cd含量较低,年平均含量分别为4.46×10-3mg/L、14.2×10-3mg/L、0.795×10-3mg/L、0.588×10-3mg/L,总体上表层海水中Cu、Zn、Pb、Cd的含量均略低于底层海水。各季度海水中重金属含量的比较结果为:Cu的含量秋季>春季>夏季>冬季,Zn的含量夏季>春季>秋季>冬季,Pb的含量秋季>夏季>春季>冬季,Cd的含量冬季>夏季>秋季>春季。湛江港湾的Cu、Zn、Pb、Cd的含量均在中部水域湛江港码头核心作业区最高,港湾外较低;Zn、Cd在港湾内的含量较高。按照单因子污染指数法评价,湛江港湾海水中的Cu、Zn、Pb、Cd含量均低于国家二类海水水质标准规定的限值,水质较好。  相似文献   

2.
徐闻珊瑚礁保护区营养盐时空分布特征   总被引:2,自引:1,他引:1  
2006年8月(夏季)、2006年11月(秋季)、2007年2月(冬季)和2007年4月(春季)在徐闻珊瑚礁自然保护区灯楼角至流沙湾近岸海域调查徐闻珊瑚礁保护区的营养盐变化及空间分布特征。结果表明:徐闻珊瑚礁保护区水域溶解态无机氮以NO3--N为主,其含量超过总溶解无机氮的50%;各站点NO2--N含量相对较低,冬季NO3--N和NH4+-N含量均高于其它季节;无机磷含量在0mg/L~0.030mg/L之间变化;活性硅含量表现为夏秋季节高、冬春季节低;表层水体硝酸盐氮/无机磷原子比值(N/P)夏季较低,不存在无机磷受限情况,而冬季N/P整体较高,此时水体主要受无机磷限制。  相似文献   

3.
【目的】揭示舟山附近海域不同功能区之间微微型自养浮游生物的时空分布。【方法】于2017年冬季、2018年春季、夏季、秋季,在舟山岛附近近岸海域不同功能区中选取6个典型站位,采集表层海水,获得24个样品。运用流式细胞仪技术对样品进行微微型自养浮游生物丰度检测,并分析其相关的环境因子及其时空分布特点。【结果】聚球藻(Synechococcus,Syn)丰度的季节分布由大到小依次为冬、春、秋、夏,微微型自养真核生物(Picoeukaryotes, Euk)丰度的季节分布由大到小依次为夏、秋、冬、春。相关性分析表明,春季,聚球藻与微微型真核浮游植物丰度均与pH呈显著正相关关系(P <0.05),微微型自养真核生物丰度与COD含量呈显著正相关关系(P <0.05);秋季,微微型自养真核生物丰度与NH_4~+、NO_2~-、Chl-a含量呈显著正相关关系(P <0.05),冬季,微微型自养真核生物和聚球藻丰度均与Chl-a含量呈显著正相关关系(P <0.05)。【结论】舟山附近近岸海域微微型自养浮游生物的丰度可直接或间接反映海域污染情况,可作为检测水体污染的指标之一。  相似文献   

4.
根据2010~2011年中街山列岛水域4个季节的渔业资源调查资料,分析了该水域虾类资源密度和群落多样性,并探讨了底层温度、底层盐度和水深对虾类数量分布和多样性的影响.结果表明:共有虾类20种,隶属于9科18属;广温广盐种无论在种类数还是尾数密度与生物量均占主导地位;虾类生物量和尾数密度在季节分布上,以冬季最高,冬季均与春、夏和秋三季呈显著差异(p值<0.05);平面分布上,生物量与密度指数总体上呈南北高、中间低,东部高西部低的特征;生物量与平均底温显著相关(P<0.05),与平均底盐和水深相关性较差(p值>0.05);葛氏长臂虾、细巧仿对虾、中国毛虾、日本鼓虾和中华管鞭虾为四季的优势种,且均属广温广盐种;虾类群落Margalef丰富度指数为0.61~1.09,Shannon-Wiener多样性指数为0.76~1.31,Pielou均匀度指数为0.50~0.70,其中丰富度指数和多样性指数春季与冬季均存在显著差异(P<0.05),均匀度指数秋季与冬季存在显著差异(p值<0.05).  相似文献   

5.
根据2014年冬、夏季北部湾2个航次的调查数据,采用分层聚类和典范对应分析研究北部湾桡足类群落的结构特征及环境适应性。结果表明,冬、夏季共鉴定出桡足类124种,其中冬季62种,夏季108种;冬、夏季优势种均为7种,冬季以亚强真哲水蚤(Subeucalanus subcrassus)、锥形宽水蚤(Temora turbinata)、精致真刺水蚤(Euchaeta concinna)为主,夏季则以异尾宽水蚤(T.discaudata)、高斯光水蚤(Lucicutia gaussae)为主。北部湾桡足类大致可分为北部群落、中部群落和湾口群落等3个群落;冬季多样性一般(Ⅳ级水平),夏季多样性较好(Ⅱ或Ⅲ级水平)。典范对应分析表明,冬季主要影响因子是海平面高度,夏季则是水深。温度和盐度与北部群落呈负相关关系,与湾口群落呈正相关关系。冬、夏季桡足类空间分布格局差异有统计学意义(P0.01)。  相似文献   

6.
根据1997年8月~1998年11月的调查数据,本文分析和评价了红海湾4个不同水域营养水平的时空分布特点.红海湾水域E值的空间分布从北向南呈逐渐递减的趋势,即长沙湾滩涂养殖区>长沙湾浅海养殖区>自然水域、龟龄岛水域,其中长沙湾滩涂养殖区和长沙湾浅海养殖区有机污染十分明显,达高富营养化程度和富营养化程度,自然水域和龟龄岛水域则营养状况相似,基本上未受到明显的有机污染.E值的季节变化趋势为春季>秋季>夏季>冬季,除冬季处于贫营养状况外,其余3个季节均达富营养化程度,其中以春季有机污染最为严重,达高富营养化程度.  相似文献   

7.
以北部湾1999年7月至2009年6月11年的Sea Wi FS卫星遥感颗粒无机碳度资料为基础,研究北部湾颗粒无机碳浓度的时空分布特征,并初步探讨其可能的海洋动力调控机制。结果表明:在季节变化上,整个冬季北部湾颗粒无机碳浓度普遍较高,表现出季节平均最大值(0.012 mol·m-3),春季普遍较低(0.004 mol·m-3),表现出全年最低水平;不同区域的最高水平出现的季节却有所不同:北部湾北部沿岸区域颗粒无机碳浓度在秋季较高,海南岛西部大部分海域在冬季较高,北部湾西北部沿岸则在夏季较高;在空间分布上,近岸海区的颗粒无机碳浓度明显高于海湾中央区域,北部湾北部海域普遍高于南部海域,东部海域高于西部海域。综合相关分析表明,北部湾颗粒无机碳浓度的这一时空分布特征主要同季风的强弱及风向有关,同时也可能与海表温度、流场(如沿岸上升流等)及陆地径流量等有关。  相似文献   

8.
【目的】研究2021年春季北部湾北部近岸浮游植物叶绿素a(Chl-a)的分布特性及影响机制。【方法】对2021年春季北部湾北部近岸海域8个站位的现场Chl-a浓度与环境因子数据进行时空分析,利用matlab绘制等值线剖面图和相关性分析等手段,分析Chl-a的分布特征及其响应机制。【结果】1)Chl-a与海表温度(SST)的高值区均在三娘湾;2)SST、浊度(TUR)和氮磷营养盐为影响北部湾北部沿岸海域浮游植物生长的主要理化因子;3)防城港Chl-a和总溶解无机氮最大值存在9 d的显著滞后正相关,在廉州湾有显著滞后负相关,而在钦州湾有较好同步相关。【结论】2021年春季研究区域Chl-a时间变化主要受陆源输运、光照和不规则全日潮影响。不同区域Chl-a空间分布的影响因子有差异,防城港的藻类生长受营养盐限制;高营养盐的廉州湾水体因高TUR光照减弱,藻类受光限制;钦州湾和三娘湾的藻类均不受营养盐和光限制,且三娘湾的SST相对更适宜生长,该区初级生产力最高。  相似文献   

9.
根据2013年11月、2014年2、5、9月在南麂列岛国家海洋自然保护区浅海区域的渔业资源调查资料,研究南麂列岛浅海区域的鱼类种类组成及数量分布,并对其与水文环境因子之间的关系作定量分析。结果表明,南麂列岛浅海区域鱼类有92种,隶属15目、49科、74属,鱼类种数春季(55种)冬季(45种)秋季(44种)夏季(34种),其中优势种为龙头鱼(Harpodon nehereus)、六指马鲅(Polynemus sextarius)、六丝钝尾虾虎鱼(Amblychaeturichthys)、凤鲚(Coilia mystus)、棘头梅童鱼(Collichthys lucidus)和绿鳍鱼(Chelidonichthys kumu)等6种。鱼类生物量各季节由高到低依次为夏季(825.87 kg)冬季(160.05 kg)秋季(139.14 kg)春季(124.94kg)。典范对应分析认为,底层盐度和水深是影响调查海域鱼类种类组成和数量分布的主要环境因子。  相似文献   

10.
西南地区空中云水量分布特征及变化趋势   总被引:1,自引:0,他引:1  
为了能更好的合理开发空中水资源,采用NCEP 1980~2009年云水量的逐月再分析资料,通过统计和EOF分析等方法,研究了30年来西南地区(云南、贵州、重庆、四川)云水量的时空分布特征和变化趋势。结果表明:西南地区年和季节云水量分布均具有明显的地区性差异,东南多,西北少,最小值出现在四川西部高原地区;云水量在夏季最多,春季略高于秋季,冬季最少;逐月云水量呈近似的正态分布,1月到6月逐渐增加,7月到12月逐渐减少;西南地区云水量的空间变化既存在南部与北部相反的变化趋势,也存在整体一致型。  相似文献   

11.
依据香港特别行政区环境保护署于1999—2007年106个航次的调查资料,结合国家海洋局南海分局于1998—2007年10个航次的调查资料,简要描述和分析大鹏湾海水中可溶性无机氮(DIN)和可溶性无机磷(DIP)含量的多年平均分布变化。结果表明,DIN和DIP含量均夏、冬季较高,而春、秋季较低;受香港和深圳等陆源排放影响,四季吐露港西部和沙头角海区域的DIN和DIP含量普遍比其他区域高;夏季南澳养殖场附近水域的DIN也明显较高,可能与养殖场的饵料投放有关。大鹏湾海水中平均氮磷原子比大于16,而DIN和DIP的平均含量分别为0.069和0.009 mg/L。夏季,由于外海高盐水的入侵,底层水中DIN和DIP含量明显高于表层。9 a调查期间,大鹏湾香港海区海水中DIN和DIP含量的年际变化呈较明显下降趋势,而氮磷原子比的年际变化则呈上升趋势。  相似文献   

12.
A severe Cochlodinium geminatum red tide (>300 km2) was observed in the Zhujiang (Pearl) River estuary, South China Sea in autumn 2009. We evaluated the environmental conditions and phytoplankton community structure during the outbreak. The red tide water mass had significantly higher dissolved inorganic phosphate (DIP), ammonia, and temperature, but significantly lower nitrite, nitrate, dissolved inorganic nitrogen (DIN), and DIN/DIP relative to the non-red-tide zones. The phytoplankton assemblage was dominated by dinoflagellates and diatoms during the red tide. C. geminatum was the most abundant species, with a peak density of 4.13×107 cell/L, accounting for >65% of the total phytoplankton density. The DIN/DIP ratio was the most important predictor of species, accounting for 12.45% of the total variation in the phytoplankton community. Heavy phosphorus loading, low precipitation, and severe saline intrusion were likely responsible for the bloom of C. geminatum.  相似文献   

13.
INTRODUCTIONNandPinputtedintoJiaozhouBaybyriversandbysewageeffluentsofcities ,havemadetheBaybecomemoreandmoreeutrophicdaybyday .Shen ( 1994)thoughtthatphytoplanktongrowthwaslimitedbythechangefromnitrogentophosphorous ;andthatthesilicateconcentrationinJiaozh…  相似文献   

14.
Analysis and comparison of Jiaozhou Bay data collected from May 1991 to February 1994 (12 seasonal investigations) provided by the Ecological Station of Jiaozhou Bay revealed the characteristic spatiotemporal variation of the ambient concentration Si∶DIN and Si∶16P ratios and the seasonal variation of Jiaozhou Bay Si∶DIN and Si∶16P ratios showing that the Si∶DIN ratios were <1 throughout the year in Jiaozhou Bay; and that the Si∶16P ratios were <1 throughout Jiaozhou Bay in spring, autumn and winter. The results proved that silicate limited phytoplankton growth in spring, autumn and winter in Jiaozhou Bay. Analysis of the Si∶DIN and Si∶P ratios showed that the nutrient Si has been limiting the growth of phytoplankton throughout the year in some Jiaozhou Bay waters; and that the silicate deficiency changed the phytoplankton assemblage structure. Analysis of discontinuous 1962 to 1998 nutrient data showed that there was no N or P limitation of phytoplankton growth in that period. The authors consider that the annual cyclic change of silicate limits phytoplankton growth in spring, autumn and winter every year in Jiaozhou Bay; and that in many Jiaozhou Bay waters where the phytoplankton as the predominant species need a great amount of silicate, analysis of the nutrients N or P limitation of phytoplankton growth relying only on the N and P nutrients and DIN∶P ratio could yield inaccurate conclusions. The results obtained by applying the rules of absolute and relative limitation fully support this view. The authors consider that the main function of nutrient silicon is to regulate and control the mechanism of the phytoplankton growth process in the ecological system in estuaries, bays and the sea. The authors consider that according to the evolution theory of Darwin, continuous environmental pressure gradually changes the phytoplankton assemblage's structure and the physiology of diatoms. Diatoms requiring a great deal of silicon either constantly decrease or reduce their requirement for silicon. This will cause a series of huge changes in the ecosystem so that the whole ecosystem requires continuous renewal, change and balancing. Human beings have to reduce marine pollution and enhance the capacity of continental sources to transport silicon to sustain the continuity and stability in the marine ecosystem. This study was funded by the NSFC (No. 40036010) and subsidized by Special Funds from the National Key Basic Research Program of P. R. China (G199990437), the Postdoctoral Foundation of Ocean University of Qingdao, the Director's Foundation of the Beihai Monitoring Center of the State Oceanic Administration and the Foundation of Shanghai Fisheries University.  相似文献   

15.
Eutrophication has emerged as a key environmental problem in Chinese coastal waters, especially in the Changjiang (Yangtze) River estuary. In this area, large nutrient inputs result in frequent harmful algal blooms and serious hypoxia in bottom waters. Four cruises were made in the estuary in 2006 to assess the concentration and distribution of dissolved inorganic nitrogen (DIN) and phosphorus (DIP). The concentration of DIN decreased gradually in a linear relationship with salinity from the river mouth to ...  相似文献   

16.
Nutrient and eutrophication characteristics of the Dongshan Bay,South China   总被引:1,自引:0,他引:1  
We recorded NO 3-N, NO 2-N, NH 4-N, PO 4-P, SiO 3-Si, salinity, and temperature data at 10 stations in the Dongshan Bay in May, June, July, August, October, and November 2008, analyzing nutrient and eutrophication characteristics. The mean concentration of dissolved inorganic nitrogen(DIN) was 0.30–0.40 mg/dm 3; generally, NO 3-N was the main form in most areas. The mean concentrations of PO 4-P and SiO 3-Si were 0.040–0.060 mg/dm 3 and 1.00–1.50 mg/dm 3, respectively. We proved that the majority of the SiO 3-Si in the Dongshan Bay came from the Zhangjiang River, with some coming from the Bachimen Strait. DIN originated from both the Zhangjiang River and the Bachimen Strait. Most PO 4-P originated from the Bachimen Strait, and some came from the Zhangjiang River. We found that P was an overall limiting factor to the phytoplankton community in most of the Dongshan Bay, and that Si and N were in surplus. However, near the Bachimen Strait Si became a limiting factor, especially for diatoms, while P and N were in comparative surplus. We used a potential eutrophication assessment method to analyze eutrophication, and showed that the most serious eutrophication occurred near the Zhangjiang River estuary and near the Bachimen Strait. In 2008, DIN levels were four times higher than that in 1988; PO 4-P levels were threefold higher, while SiO 3-Si was approximately double. Dissolved nutrients increased between 1988 and 2008. DIN increased at the greatest rate comparing to PO 4-P and SiO 3-Si, thus the N/P and N/Si mol ratios increased. Further studies on the effects of high DIN concentrations on the phytoplankton communities and marine ecosystems of the Dongshan Bay are needed.  相似文献   

17.
An environmental capacity model for the petroleum hydrocarbon pollutions (PHs) in Jiaozhou Bay is constructed based on field surveys, mesocosm, and parallel laboratory experiments. Simulated results of PHs seasonal successions in 2003 match the field surveys of Jiaozhou Bay resaonably well with a highest value in July. The Monte Carlo analysis confirms that the variation of PHs concentration significantly correlates with the river input. The water body in the bay is reasonably subjected to self-purification processes, such as volatilization to the atmosphere, biodegradation by microorganism, and transport to the Yellow Sea by water exchange. The environmental capacity of PHs in Jiaozhou Bay is 1500 tons per year IF the seawater quality criterion (Grade Ⅰ/Ⅱ, 0.05 mgL-1) in the region is to be satisfied. The contribution to self-purification by volatilization, biodegradation, and transport to the Yellow Sea accounts for 48%, 28%, and 23%, respectively, which make these three processes the main ways of PHs purification in Jiaozhou Bay.  相似文献   

18.
19.
Using historical and 2010 field data, the distribution of nutrients in the northern Beibu Gulf of China is described. There was a decreasing trend in the concentration of nutrients from the north coast to offshore waters of the northern Beibu Gulf, reflecting the influence of inputs from land-based sources. High concentrations of dissolved inorganic nitrogen (DIN) and phosphate (PO4-P) occurred mainly at Fangchenggang Bay, Qinzhou Bay, and Lianzhou Bay. Four different methods were used to assess eutrophication. The trophic status of the Beibu Gulf was characterized using the single factor, Eutrophication index (El), Trophic index (TRIX) and Assessment of Estuarine Trophic Status (ASSETS) methods. Based on nutrient concentrations, 73.9% of DIN and 26.7% of PO4-P samples exceeded the fourth grade Seawater Quality Standard of China. Eutrophication index values varied widely, but higher levels of eutrophication were generally found in bays and estuaries. TRIX values ranged from 2.61 to 7.27, with an average of 4.98, indicating a mesotrophic and moderately productive system. A positive correlation between TRIX and harmful algal species richness and abundance was observed. The ASSETS model evaluates eutrophication status based on a Pressure-State-Response approach, including three main indices: influencing factors, overall eutrophic condition, and future outlook. The Beibu Gulf was graded as moderate using ASSETS. The single factor and Chinese nutrient index methods were considered inadequate for the assessment of trophic status. TRIX can be used as an indicator of trophic state and ASSETS showed good potential to assess eutrophication. The results of TRIX and ASSETS depend on threshold values. To establish these values, further research is required within the northern Beibu Gulf.  相似文献   

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