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1.
大亚湾网箱养殖区生物—化学特性与营养状况的周日变化   总被引:7,自引:0,他引:7  
根据1998年11月对大亚湾大棚澳网箱养殖区进行的定点24h连续水质监测资料,分析并探讨了该养殖区海水生物-化学各要素的垂直分布和周日变化规律,并用单项指标评价法和改进的营养状态质量指数(NQI)法,参照营养指数(E)对该网箱养殖区涨水的营养状况进行了评价和研究,结果表明,各项要求的平均值大最都表层>中层>底层;周日变化主要受潮汐运动和海水中生物的节律性生理活动的综合影响;表层海水的富营养化率明显高于中层海水,其各单项指标处于中度-富营养状态,而中层和底层海水则分别处于贫-中度和贫-富营养状态;PO4-P相对贫乏,为养殖区富营养化的最关键限制因素。  相似文献   

2.
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   

3.
【目的】分析评价2010-2017年嵊泗马鞍列岛保护区海域的水质状况。【方法】采用水质有机污染指数(A)法进行水质有机污染评价,采用富营养化指数(E)法和营养状态质量指数(INQ)法进行水质富营养化评价。【结果】该保护区海域水质化学需氧量(COD)和溶解氧(DO)符合第一类海水水质标准,无机磷(DIP)含量有3个年份符合第一类海水水质标准,其余年份超过第一类但符合第二类海水水质标准,无机氮(DIN)质量浓度超标严重,2015年达到0.674 mg/L;叶绿素a(Chl-a)本底含量较高,适宜条件下使得浮游植物大量繁殖,Chl-a含量急剧上升,并容易诱发赤潮;有机污染指数评价显示,2012-2015年水质有机污染状况达到中度污染以上,并且有3年达到严重污染级别,最大A值为2014年和2015年的4.10,2016年污染最轻,为开始受到污染级别;富营养化指数和营养状态质量指数评价显示,最大E值和INQ值分别为2012年的4.29和2010年的8.59,DIN含量高是富营养化的主要贡献因子。【结论】该保护区海域水质主要污染因子为DIN,水质有机污染状况呈现年度波动状态,水质富营养化较严重。  相似文献   

4.
根据2004年6月中旬在鳌山湾海区所取得的底层海水营养盐资料,分析了青岛鳌山湾海区营养盐的平面分布特征;运用绝对限制法则和相对限制法则确定了鳌山湾海区的营养盐限制因子;采用营养状态综合指数法和分类分级富营养化评价模式对鳌山湾海域的营养状况进行了评价。结果表明:鳌山湾营养盐限制因子为磷(P),该海区由缺氮转变为缺磷,营养盐结构发生了根本性变化,且该海域无富营养化现象,水质较好。  相似文献   

5.
根据“压力-状态-响应”(PSR)框架模型,对南四湖健康状态进行评价.选取南四湖流域人口密度、工农业供水需求、富营养化程度、南四湖生物多样性指数、环保投资指数等能够充分反映南四湖压力、状态和响应的指标构建评价指标体系;通过专家经验赋值法对各评价指标进行权重确定,并对指标进行标准化赋值;提出了南四湖健康评价模型并且得出南...  相似文献   

6.
西津水库网箱养殖区浮游植物特征及水质营养状态   总被引:2,自引:0,他引:2  
于2006年10月至2008年7月对西津水库米埠坑网箱养殖区浮游植物进行两个年度共8次调查。第1年发现浮游植物6门53属,冬季出现种属最多,达到43属,春、夏季最少,为35属,浮游植物年平均数量为35.18×104 L-1,平均生物量为1.07 mg·L-1。第2年度采集到浮游植物6门47属,以春季出现种属最多,达到40属,夏季最少,为29属,第2年浮游植物年平均数量低于第1年,为19.77×104 L-1,生物量高于第1年,达到1.22 mg·L-1。综合营养指数评价结果显示,米埠坑网箱养殖区处于中营养水平,有向富营养化过渡的趋势。  相似文献   

7.
青岛鳌山湾海区营养结构分析与营养状况评价   总被引:2,自引:0,他引:2  
根据2004年6月中旬在鳌山湾海区所取得的底层海水营养盐资料,分析了青岛鳌山湾海区营养盐的平面分布特征;运用绝对限制法则和相对限制法则确定了鳌山湾海区的营养盐限制因子;采用营养状态综合指数法和分类分级富营养化评价模式对鳌山湾海域的营养状况进行了评价。结果表明:鳌山湾营养盐限制因子为磷(P),该海区由缺氮转变为缺磷,营养盐结构发生了根本性变化,且该海域无富营养化现象,水质较好。  相似文献   

8.
提出了适用于16个富营养化指标的湖泊营养状态指数公式,并对指数公式中的参数采用粒子群算法进行优化,得到对16项指标都适用的营养状态指数公式.实例分析表明,优化后的湖泊营养状态指数公式计算简单、实用,具有客观性、可比性和通用性.因而,能够对湖泊富营养化进行较好的评价.  相似文献   

9.
对长岛北四岛海洋牧场海域101个表层沉积物和102个表层海水样进行取样调查,开展表层沉积物类型、粒度、表层沉积物和海水重金属等指标分析测试,采用单因子污染指数法、富集系数法和潜在生态危害指数法评价该区表层沉积物潜在生态风险,采用海水水质分类和单因子污染指数法评价表层海水污染情况。表层沉积物结果表明:沉积物为泥质砂质砾、砾质泥质砂、砾质泥、含砾泥质砂、砂、粉砂质砂和砂质粉砂,平均粒径介于2.44~5.44Ф;Hg、Cu、Zn、Pb、Cd、As、Cr、硫化物和石油类都符合第一类标准,属于清洁沉积物;Cr、Cu、Pb、Zn、Cd、Hg和As富集系数均<1,处于低度污染水平;Cr、Cu、Pb、Zn、Cd、Hg和As单项潜在生态危害系数Eir介于0.56~30.71之间,RI均值为66.27,远低于低度生态危害的划分标准值。表层海水结果表明:21个站位受到Hg污染,略高于第一类标准,满足第二类标准,主要位于研究区西北部、西中部和东北部海域,其余指标均符合规定第一类标准;Hg、Cu和Zn含量处于较清洁环境范围内,As、COD、石油类、Pb、Cr和Cd含量处于自然本底环境。根据海底沉积物和海水分析结果得出,长岛北四岛海域海洋牧场规划区底质和水质环境适宜建设海洋牧场。  相似文献   

10.
【目的】研究海南岛近岸海域表层海水化学需氧量(COD)的时空分布特征,评价COD污染水平,研究区域COD浓度与多种环境因子之间的关系。【方法】根据2016年枯水季、丰水季和平水季海南岛近岸海域表层海水现场调查资料,进行单因子指数法和综合指数法分析。【结果】海南省近岸海域表层海水COD的平均质量浓度为(0.75±0.43) mg/L,浓度范围为0.14~2.74 mg/L;COD浓度高值区主要分布在龙尾河口临近小海海域,枯水季研究海域表层海水COD污染水平高于丰水季节;COD对富营养化的贡献范围为38.2%~69.7%,平均贡献率为(51.0±5.1)%,贡献率随着富营养化指数的增加而减小;3个季节COD与盐度均存在显著负相关(P<0.01)。【结论】COD时空分布主要受陆源输入和水动力过程的影响。COD是影响海南岛近岸海域富营养化的重要因子但非决定性因子。随着富营养化程度增加,来自营养盐对富营养化贡献更为显著。  相似文献   

11.
Increasing numbers of approaches to assess eutrophication,such as estuarine trophic status,the Oslo-Paris Commission Common Procedure,and the Water Framework Directive,focus on the symptoms of eutrophication.In China,however,nutrient index methods dominate the assessment of coastal waters.In this study,an integrated method that includes both water quality and ecological response was compared with the Northwest Pacific Action Plan(NOWPAP)Common Procedure.Observation data from Jiaozhou Bay,Shandong,China,were used in a comparison of the two methods in a trophic status study.Overall,both clearly revealed a high level of nutrient enrichment in the bay,indicated by high nutrient concentrations.Though the two methods differed in their methodological design in the assessment of the ecological effects of nutrient enrichment,they have acquired similar results:the integrated method suggested that the status was good,and the NOWPAP Common Procedure suggested that the status was low(indicating that the bay had no serious eutrophication problem).The introduction of filter feeders(shellfish aquaculture)into the bay on a reasonable scale may have been effective in mitigating eutrophic conditions,and perhaps explains the low ecological impacts there.Our results will be useful to ecosystem-based eutrophication management in the bay and in similar areas.  相似文献   

12.
An integrated methodology for eutrophication assessment,which integrates both water quality indicators(causative factors) and ecological response indicators(effect factors),is described.It is then applied to rank the eutrophication status of the years 2007 and 2008 in the southwest Bohai Sea.The assessment model identified that north Bohai Bay and west Laizhou Bay were the two areas with the most serious eutrophication problems in the southwest Bohai Sea.In addition,compared to that in the west Laizhou Bay,the eutrophication conditions in the north Bohai Bay was more serious in both years.Eutrophication problems such as harmful algal blooms(HABs) and low dissolved oxygen(DO) events in north Bohai Bay were frequent.The integrated method outmatched the currently used Chinese nutrient index method by definitely identifying areas with the most serious eutrophication problems,while the nutrient index method gave ambiguous results between the two years.Inclusion of both causative factors and effect factors,combining concentration,spatial coverage and frequency of indicators,as well as use of multi-season monitoring datasets in the methodology result in a more accurate,representative and useful assessment.  相似文献   

13.
Sanduao is an important sea-breeding bay in Fujian, South China and holds a high economic status in aquaculture. Quickly and accurately obtaining information including the distribution area, quantity, and aquaculture area is important for breeding area planning, production value estimation, ecological survey, and storm surge prevention. However, as the aquaculture area expands, the seawater background becomes increasingly complex and spectral characteristics differ dramatically, making it difficult to determine the aquaculture area. In this study, we used a high-resolution remote-sensing satellite GF-2 image to introduce a deep-learning Richer Convolutional Features(RCF) network model to extract the aquaculture area. Then we used the density of aquaculture as an assessment index to assess the vulnerability of aquaculture areas in Sanduao. The results demonstrate that this method does not require land and water separation of the area in advance, and good extraction can be achieved in the areas with more sediment and waves, with an extraction accuracy 93%, which is suitable for large-scale aquaculture area extraction. Vulnerability assessment results indicate that the density of aquaculture in the eastern part of Sanduao is considerably high, reaching a higher vulnerability level than other parts.  相似文献   

14.
红海湾水产养殖示范区水质综合评价   总被引:3,自引:0,他引:3  
红海湾是广东省非常重要的海水养殖示范区。为了维系和保护红海湾规模化水产养殖示范区的优良生态环境 ,1 997年 4月至 1 998年 1 2月对红海湾水域水质的时空变化趋势和质量状况进行了研究与评价。结果表明 ,红海湾海水综合质量总体上处于相对清洁水平 ,但浅海养殖区和长沙湾养殖区有机污染明显 ,分别达富营养化和高富营养化程度。DIN和IP是水质富营养化的主要因素 ,而石油类、Cu、COD是重点控制的优先污染物。  相似文献   

15.
Water samples were collected in 120 stations in the Bohai Sea of China to analyze the distribution of dissolved nutrients and assess the degree of eutrophication in August 2002. The result shows that the average concentration of DIN increased and the PO4-P concentration sharply decreased compared to the previous data of corresponding period. The high concentrations of DIN and PO4-P occurred in coastal waters, especially in the bays and some river estuaries, while the high concentrations of SiO3-Si in the surface and middle depth occurred in the central area of the Bohai Sea. The average ratio of DIN/ PO4-P was much higher than the Redfield Ratio (16:1). Apparently, PO4-P was one of the limiting nutrient for phytoplankton growing in the sea. The average concentrations of DON and DOP were higher than their inorganic forms. The results of eutrophication assessment show that 22.1% of all stations were classified as violating the concentration levels of the National Seawater Quality Standard (GB 3097-1997) for DIN and only 3.9% for PO4-P. The average eutrophication index in the overall area was 0.21±0.22 and the high values occurred in Bohai Bay, Liaodong Bay and near the Yellow River estuary. This means that the state of eutrophication was generally mesotrophic in the Bohai Sea, but relatively worse in the bays, especially some river estuaries.  相似文献   

16.
Habitat plays a critical role in regulating fish community structure. Using the data collected from a monthly trammel net survey in Ma’an archipelago off the east coast of China, we evaluated impacts of five different habitats(artificial reefs, mussel farms, cage aquaculture, rocky reefs and soft bottom) on fish assemblages. This study suggests that artificial reefs(AR) have significantly higher species richness, abundance and diversity than mussel farms(MF) or soft bottom(SB) habitats during most seasons, and that fish taxa in the AR habitats are similar to those in the rocky reef(RR) habitats. Two different fish assemblage patterns were revealed in the study area using non-metric multidimensional scaling ordination: an assemblage dominated by reef fishes(especially by Scorpaenidae species) in AR, RR and cage aquaculture(CA) habitats and an assemblage dominated by Sciaenidae species in MF and SB habitats. We suggest that reef fishes play a key role in differentiating fish community structures in the study area. Although few differences in fish abundance and diversity were found between the CA and SB habitats, a more diverse age structure was observed in the CA habitats. A much more complex fish assemblage and enhanced population of local species were established as a result of the presence of both floating and fixed artificial structures, probably through improved survival rates.  相似文献   

17.
1 INTRODUCTION Increasing eutrophication of lakes in recent years as a result of human impact has become a se- rious environmental problem in China. Many lakes in the Jianghan Plain, South China, for example, especially near major cities, have been eutrop…  相似文献   

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