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21.
利用川渝地区1960-2006年逐月降水量资料和美国NOAA Research/ESRL逐月再分析海表温度(SST)资料,采用经验正交函数分解(EOF)、点相关、合成分析和奇异值分解(SVD)等方法,详细探讨了川渝地区夏季降水量与赤道印度洋海温的关系。结果表明:川渝夏季降水量EOF分解得出的第一模态占总方差的27.8%,降水量的空间分布为全区一致型;川渝地区夏季降水量与赤道印度洋海温区域(10°N~16°S,57~77°E)(下称关键区)存在显著相关。合成分析指出关键区海温异常偏暖(冷),对应川渝地区夏季降水量比常年同期偏多(少)。通过SVD分解发现,川渝地区夏季降水量与关键区海温呈显著相关,具体表现为印度洋关键区海温与川西高原和盆地东部夏季降水量呈同位相变化,与盆地中部降水量呈反位相变化。  相似文献   
22.
石油污染对牡蛎超显微结构毒性效应的研究   总被引:3,自引:0,他引:3  
采用电子显微镜观察石油污染对牡蛎生殖腺和肝胰腺组织细胞的毒性作用。结果显示,石油污染对牡蛎具有明显的慢性毒害作用,50 mg/L浓度组,实验10 d的牡蛎,其组织细胞受石油污染不明显;当实验时间为30 d时,出现明显的毒性效应,细胞核核膜肿胀,染色质聚集并边际化,细胞核崩解,细胞坏死,组织萎缩,线粒体的变化较其他细胞器对石油污染较敏感,受损坏的程度较重。  相似文献   
23.
北太平洋柔鱼渔场时空分布与海洋环境要素的研究   总被引:9,自引:0,他引:9  
根据2010 年7~9月和2011年7~10月“舟渔1301#” 2个航次的北太平洋柔鱼渔场海上调查资料,利用渔获生产数据?海况天气数据以及同期的卫星遥感获取的海表面温度(SST) ?海表盐度(SSS)及叶绿素a (Chl-a)浓度和海流等数据,分析柔鱼的中心渔场分布与海洋环境的变动关系.研究结果显示:整个调查期间渔获频次在SST和Chl-a因子上均呈正态分布,渔场高产的最适SST范围为18~20℃, 最适SSS范围为33.60‰~34.80‰, 最适Chl-a浓度范围为0.08~0.24mg/m3,其中SST与柔鱼渔场之间有较好的匹配关系,中心渔场通常位于18~20℃的等温线附近,且位置一般出现在冷水团和暖水团交汇区的冷水团一侧;中心渔场位于亲潮和黑潮交汇混合区的向北一侧,离交汇地带的距离较近,而且随着时间的推移,渔汛期间中心渔场的位置逐步往其向西北方向移动.总体上多个环境因子皆可作为确定潜在中心渔场的指标,但以海表水温为最佳,另外辅助寒?暖流的交汇情况以及Chl-a浓度?天气海况等因素来综合分析,判断渔场的中心位置会更准确.  相似文献   
24.
A large sample of 1664 companies—69 directly working in the ocean economy—distributed across 19 industrial sectors was investigated to explore awareness and activation regarding direct and indirect pressures on the ocean, their responses to these pressures, and the disclosure tools used. We examined their accountability and disclosure practices on sustainable development goals (SDGs) using the drivers, pressures, state, welfare, and response accounting framework. Based on their 2019 sustainability reports, just 7% of the companies assessed disclosed on SDG14. However, 51% of these companies can be considered as aware, albeit to varying degrees, of the pressures their industries place on the oceans, 44% deploy mitigating activities, and 26% are aware and actively lead business responses to ocean challenges. Although we have seen just early responses in addressing ocean challenges, companies’ awareness and activation must converge to achieve ocean sustainability and move businesses into a truly blue economy.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-022-01784-2.  相似文献   
25.
于2018年10月9日~11月1日采集西太平洋表层海水,通过营养盐添加船基培养实验,研究了不同营养盐条件下浮游植物的生长及其释放挥发性卤代烃(VHCs)含量的动态变化规律.结果表明,与对照组相比,氮磷营养盐的添加对叶绿素a(Chl-a)的含量和三氯乙烯(C2HCl3),四氯乙烯(C2Cl4),一氯二溴甲烷(CHBr2Cl),三溴甲烷(CHBr3)的释放量表现出显著促进作用,但促进程度与添加氮磷营养盐的浓度及比值密切相关.高浓度氮更有利于浮游植物的生长及C2HCl3和C2Cl4的释放.N/P比符合Redfield比值更有利于CHBr2Cl和CHBr3的释放.相比NO3--N,NH4+-N的添加更有利于4种VHCs释放.  相似文献   
26.
连云港港口渔船防污工作的调查与思考   总被引:2,自引:0,他引:2  
蒋惠林  周毅 《交通环保》1999,20(5):34-36,38
通过对连云港港口渔船防污工作的现场调查,分析了存在的问题,对渔船的污染危害进行了评估,并提出了对策。  相似文献   
27.
Abstract:  In the first comprehensive reviews since 1969, two high-level reports on the status of U.S. marine ecosystems and resources have been released: that of the nongovernmental Pew Oceans Commission in 2003 and that of the congressionally mandated U.S. Commission on Ocean Policy in 2004 . Although the two commissions differed in the breadth and depth of their mandates, their findings on the state of our oceans and need for new management approaches are similar, and their major recommendations for science, governance, management and conservation, and education echo and reinforce each other. The history behind the two commissions and the structure and objectives of each remind us of the crucial roles conservation practitioners and scientists must play in the implementation of report recommendations. The reports suggest priorities for conservation practitioners to improve science, management, conservation, governance, and education to better manage and protect ocean resources and ecosystems. To redirect activities affecting the state of global marine resources, integrated research; education and outreach by terrestrial, aquatic, and marine conservation practitioners; and a clear definition of their roles in the implementation of recommendations is essential. Marine ecosystems provide a test case of society's ability to manage complexity in human and natural systems in an integrated manner, with extensive opportunities for participation by conservation practitioners from all disciplines.  相似文献   
28.
Symbioses between dinoflagellates in the genus Symbiodinium (commonly referred to as zooxanthellae) and scleractinian corals are an essential feature for the maintenance of coral reefs. The fine-scale diversity and population structure of the zooxanthellae inhabiting the coral Pocillopora meandrina, a major reef building species in Polynesia, was examined. We used two polymorphic microsatellites to study seven populations from the South Pacific, whose host structuring has been previously investigated. The symbionts of P. meandrina showed high levels of diversity, with more than one zooxanthella genotype being identified in most of the host individuals. Genetic differentiation between symbiont populations was detected at a large scale (2,000 km) between the Tonga and the Society Archipelagos. Within the Society Archipelago, the two most remote populations (Tahiti and Bora-Bora; 200 km apart) were only weakly differentiated from each other. Statistical tests demonstrated that the symbiont genetic structure was not correlated with that of its host, suggesting that dispersal of the symbionts, whether they are transported within a host larva or free in the water, depends mainly on distance and water currents. In addition, the data suggests that hosts may acquire new symbionts after maternal transmission, possibly following a disturbance event. Lastly, the weak differentiation between symbiont populations of P. verrucosa and P. meandrina, both from Moorea, indicated that there was some host-symbiont fine-scale specificity detectable at the genetic resolution offered by microsatellites.  相似文献   
29.
The human communities and ecosystems of island and coastal southeast Africa face significant and linked ecological threats. Socioecological conditions of concern to communities, governments, nongovernmental organizations, and researchers include declining agricultural productivity, deforestation, introductions of non-native flora and fauna, coastal erosion and sedimentation, damage to marine environments, illegal fishing, overfishing, waste pollution, salinization of freshwater supplies, and rising energy demands, among others. Human–environment challenges are connected to longer, often ignored, histories of social and ecological dynamics in the region. We argue that these challenges are more effectively understood and addressed within a longer-term historical ecology framework. We reviewed cases from Madagascar, coastal Kenya, and the Zanzibar Archipelago of fisheries, deforestation, and management of human waste to encourage increased engagement among historical ecologists, conservation scientists, and policy makers. These case studies demonstrate that by widening the types and time depths of data sets we used to investigate and address current socioecological challenges, our interpretations of their causes and strategies for their mitigation varied significantly.  相似文献   
30.
Artificial neural networks (ANN) are widely used as continuous models to fit non-linear transfer functions. In this study we used ANN to retrieve chlorophyll pigments in the near-surface of oceans from Ocean Color measurements. This bio-optical inversion is established by analyzing concomitant sun-light spectral reflectances over the ocean surface and pigment concentration. The relationships are complex, non-linear, and their biological nature implies a significant variability. Moreover, the sun-light reflectances are usually measured by satellite radiometers flying at 800 km over the ocean surface, which affect the data by adding radiometric noise and atmospheric correction errors. By comparison with the polynomial fit usually employed to treat this problem, we show the advantages of neural function approximation like the association of non-linear complexity and noise filtering.  相似文献   
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