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1.
在全国海洋科技大会上,本刊记者就地球科学与海洋学科发展战略问题采访了国家自然科学基金委员会地球科学部副主任陆则慰。记者:国家自然科学基金是国家资助基础研究的主要渠道之一。国家自然科学基金委员会作为管理国家自然科学基金的主管部门,请介绍一下国家自然科学基金委的  相似文献   

2.
《Marine Chemistry》2007,103(1-2):97-102
Carbon (13C) and nitrogen (15N) stable isotope analysis has become increasingly important in the study of energy flow and tropho-dynamics in many ecosystems. Prior to analysis, samples are often pre-treated with acids to remove inorganic carbonates which may bias the results. The effects of pre-analysis acidification on isotopic values are, however, still poorly understood for marine producers (e.g. algae and cyanobacteria), and consumers (e.g. molluscs), which may confound the comparability of different studies. In this study, such effects (untreated vs. decalcified samples) were examined at two different sampling periods (summer and winter). Acidification did not seem to affect the isotopic composition of consumers, but reduced both δ13C and δ15N of producers. This effect was consistent for the two sampling periods, although both producers and consumers had more enriched δ13C and δ15N values in summer. Acidification had the most distinct, negative effect on the isotopic values of samples which had low carbonate contents. It is, therefore, important to be aware of temporal variations in sample isotopic values and especially the effects of sample treatment when attempting to compare different studies. As an attempt to standardize protocols, it is recommended that only acid-washing carbonate-rich samples is adopted as the most appropriate pre-analysis treatment.  相似文献   

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Carbon and oxygen isotope ratios of 59 samples of Mesozoic ophicalcites from the north-central Apennines were measured. Strontium content and isotope ratios were only determined for selected samples.

The data obtained (−4.1 ≤ δ 13C ≤ + 3.0; 16.5 ≤ δ 18O ≤ 30.1; 0.7076 ≤ 87Sr/86Sr ≤ 0.7086; 60 ≤ Sr ppm ≤ 1140) suggest that the carbonate cement of the Apennines ophicalcites had a marine origin.

The 18O/16O values of most of the carbonates studied, however, indicate that the rocks have interacted with hydrothermal fluids, dominantly represented by sea water. In particular, the rocks from the northern section of the Apennines apparently reequilibrated their δ 18O content at higher temperature than those from the central zone.

Strontium isotope ratios, close to the Cretaceous—Cenozoic ocean water values, are well in agreement with such a kind of sea water/ophicalcites interaction, even if the carbonate cement formed earlier during the Jurassic period.  相似文献   


4.
以科学发展观为指导保持海洋经济可持续发展   总被引:1,自引:0,他引:1       下载免费PDF全文
2005年伊始,胡锦涛总书记再次强调了以科学发展观全面推进小康社会的进程,而开发海洋,保持海洋经济的可持续发展又是推动我国经济社会发展的一项战略任务。因此,进入21世纪以来,海洋越来越成为人们关注的焦点。我们必须以新的视角重新认识海洋经济,以新的观念来指导海洋经济,以新的方法来发展海洋经济,使我国的海洋经济建设事业跨上可持续发展的时代快车。文章从我国发展海洋经济的必要性出发,分析其现状、存在的问题并提出相应的对策与措施。  相似文献   

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1 IntroductionIn January 2003, undisturbed sediments were tak-en from a grid of 22 sampling stations (from 32.5° to37°N, 122° to 125°E) during the cruise of an ecologi-cal survey of the over-winter ground for anchovy inthe Huanghai Sea. Meiofaunal abundance varied from55.3 to 152.0 ind/cm2 [(95.4 ±27.0) ind/cm2], with81% to 93% [(83.1 ±22.7) ind/cm2] of the specimensbeing nematodes. Up to now, twenty-nine species ofmarine nematodes have been recorded from theHuanghai Sea (Zhang and P…  相似文献   

6.
酸化过程对海洋沉积物中有机碳同位素分析的影响   总被引:5,自引:1,他引:5  
海洋沉积物中有机碳同位素(δ13C)可以示踪海洋生态系统中有机质来源,对环境研究具有重要意义。分析沉积物中有机物的δ13C,需要对样品进行酸化,以去除无机碳的影响。由于不同来源的沉积物中无机碳的含量和组份存在差异,需要针对样品性质,优化酸化处理过程。本研究分别选取了无机碳含量不同的温带与热带河口、海湾沉积物样品,比较了3种不同酸化过程对有机物δ13C分析的影响。研究结果表明:方法1(酸洗法)中6%H_2SO_3和1mol/L H_3PO_4对无机碳含量较高的热带河口、海湾样品去除效率较低,而2mol/L HCl去除无机碳酸盐的效果较理想。方法2(酸蒸法)并不适用于无机碳含量较高的热带河口、海湾样品;而对于无机碳含量相对较低的温带河口、海湾样品,9h酸蒸较为适宜。方法3(非原位酸洗)的结果较方法1和方法2偏正,表明其对含13C丰富的有机组分破坏较小,且方法3中残留的酸对δ13C的分析没有影响。因此,方法3是去除海洋沉积物中无机碳较理想的方法。  相似文献   

7.
Global decline of marine resources has triggered a worldwide demand for changing the way ocean resources are managed. Ecosystem-based management approaches have emerged using marine protected areas (MPA) as the main tool. Several classifications of marine protected areas benefits have been made, but all have focused only on the benefits to humans, neglecting many important benefits accrued to nature. This paper presents a new comprehensive classification of MPA benefits that will provide scientists and managers with an inclusive framework to accurately identify and account for all possible benefits derived from MPAs. The paper also analyses the methods available for valuing these benefits. A total of 99 benefits were identified within nine main categories: fishery, non-fishery, management, education/research, cultural, process, ecosystem, population and species benefits. These categories are arranged in two main divisions (direct and indirect benefits), which, at the same time, fall within the realms of benefits to humans and to nature.  相似文献   

8.
贝类杂交及杂种优势理论和技术研究进展   总被引:30,自引:2,他引:30  
中国是个海水养殖大国,也是贝类养殖大国,贝类养殖产量占中国海水养殖总产量的80%左右。目前在中国海水养殖的贝类有20余种,但主要种类如皱纹盘鲍(Haliotis discus hannai)、杂色鲍(Haliotis diversicolor)、栉孔扇贝(Chlamys farreri)、海湾扇贝(Amopecten irradians)、长牡蛎(Crassostrea gigas)、近江  相似文献   

9.
海洋生态资源的定价理论探讨   总被引:5,自引:0,他引:5  
以劳动价值论和效用价值论为基础,分析探讨海洋生态资源的价值理论,指出海洋生态资源的价值是由现实使用价值、选择价值和存在价值三部分构成;通过人类有目的的劳动把自然物变为经济物,从而形成系统的价值流;按照马克思的地租理论,海洋生态资源具有绝对地租和级差地租两种形式。  相似文献   

10.
Two new species of genus Diplopeltoides Gerlach, 1962 and two new species of genus Minolaimus Vitiello, 1970 were described based on recently collected specimen...  相似文献   

11.
孙静  黄勇 《海洋科学》2021,45(1):14-21
在对东海的自由生活海洋线虫进行分类和多样性研究中,发现2个我国新纪录种并进行了描述.深海螺旋球咽线虫Spirobolbolaimus bathyalis Soetaert&Vincx,1988的主要鉴别特征为:体表具显著的环纹,头感觉器呈乳突状,化感器螺旋形,口腔中部具有一个背齿以及一对亚腹齿,咽前后各有一个咽球;具有...  相似文献   

12.
浮式塑料薄膜袋培养海洋微藻的研究   总被引:4,自引:0,他引:4  
将塑料薄膜袋悬浮于水泥池中进行海洋微藻的三级培养。结果表明,此方法既保证了藻种培养过程中的良好条件,又能够有效地避免薄膜袋的破损漏水,操作简单,运用灵活,生产效率大大提高。  相似文献   

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区域海洋管理是对一定海洋地理空间范围内具有重要意义的区域系统进行的自觉干预和内外协调的活动。文章讨论海洋区域、区域海洋管理的概念、管理区域划分、区域海洋基本思想和管理方式等,试论区域海洋生态系统管理是海洋综合管理的新发展,认为区域海洋管理必须以生态系统管理为核心,以社会-经济-自然复合生态系统为管理对象,才能使区域海洋社会经济能够在可持续的生态系统支持下发展。  相似文献   

16.
Since 2009, there has been a shift in UK marine governance with the Marine and Coastal Access Act in which a core mechanism is marine planning, designed to replace a fragmented, ad hoc, and bureaucratic process of marine management with a strategic, integrated, and centralised system. This shift has been justified by the UK government as a more efficient procedure for delivering sustainable development (SD), which is the overarching objective of UK environmental policy. This article, which is based on data from key informant interviews and secondary sources, analyses the shift to understand its aspirations and the challenges facing it. The issues focused on include its holistic approach; its centralising tendencies; its streamlining processes; and its implicit commitment to renewable energy. In these four issues there are tensions between aspirations and challenges, and the conclusion is that the success of the new mode of marine governance depends on satisfactorily resolving these tensions.  相似文献   

17.
辽宁省海洋经济存在问题及对策研究   总被引:5,自引:2,他引:5       下载免费PDF全文
辽宁省是海洋大省,早在1986年,省委、省政府就提出了建设“海上辽宁”的战略设想,旨在通过充分利用辽宁省海洋资源优势,培育海洋支柱产业,开辟新的经济增长领域,逐步建立与辽宁陆域经济体系相适应的技术先进、结构合理的开放型海洋经济体系。我国加入世界贸易组织,必然加快辽宁省的对外开放步伐。  相似文献   

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海洋钢结构阴极保护初始极化问题及解决途径   总被引:2,自引:0,他引:2  
针对海洋钢结构阴极保护中的初期极化问题,介绍了一种新的解决方法,并通过建立模型,与传统方法进行了对比分析。结果表明,这种方法既可保证防护效果,又可节约大量阳极材料,具有非常广阔的应用前景。  相似文献   

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