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1.
《Marine Policy》2016
In 1997, Robert Costanza and his colleagues published a groundbreaking study [1] that estimated the monetary value of the contribution of the world's ecosystems to human wellbeing. The methods used were cited as preliminary and received considerable criticism [2], [3]. In two more recent peer-reviewed studies [4], [5], the authors update the original estimates of ecosystem service value and find: (1) that original per area ecosystem service values were underestimated and (2) using these revised per area values, the total global value of ecosystem services has declined. Just under ninety-five percent of the estimated loss in ecosystem service value comes from revisions by the authors in the value estimates of marine ecosystem services. These revisions include additional per area value estimates of coral reefs and coastal wetlands that are many times the value of estimates used in the original analysis. The reasons cited by Costanza et al. for the increases in revised value estimates are examined and rejected. The data are found to be insufficient for a rigorous estimate of the global value of marine ecosystems services. 相似文献
2.
In April, 1985, scientists from China and Canada made a marine enclosed ecosystem experiment cooperatively in Xiamen. The experiment was carried out in the plastic bags in a shorebased tank. To the bags, heavy metals (Cu, Hg, Zn, Pb and Cd) were added quantitatively and their effects on the primary productivity were studied. The results show that the effects of low level metal mixture (Cu 3.5-10.0, Hg 0.2-1.0, Pb 0.3-1.5, Zn 3.5-17.5, 相似文献
3.
《Journal of Sea Research》2000,43(2):105-111
The seasonal dynamics of the nanophytoplankton community (pelagic algae 2–20 μm) was studied at a location in the Southern Bight (North Sea) from October 1993 through May 1994. During the study period the cell number and biomass of the nanoalgae varied between 105–106 cells dm−3 and 16–300 μg wet weight dm−3. Several ecological events seem common to the boreal coastal nanophytoplankton communities in the winter–spring period. These are: (1) abrupt fall in abundance at the beginning of winter (late October–early November); (2) winter minimum (December–March); (3) steady increase in cell number and biomass (April–May); followed by (4) the spring maximum occurring usually in May. 相似文献
4.
This paper examines an apparent ‘early stage’ governance transformation in the Tam Giang Lagoon, Vietnam. In this context, the role of key policy windows for innovative governance practice is assessed (e.g., changes to Land and Fisheries Laws). Also examined is the emergence of recent initiatives to catalyze a wider shift in governance practice in the region, including the formation of co-management institutional networks that contribute to trust building and learning, and the allocation of collective territorial use rights for fisheries. While these changes are consistent with experiences in other coastal marine contexts, the paper shows that place-based and longitudinal research is necessary to explain and predict the conditions and incentives that catalyze governance shifts. Differences between a governance change and more fundamental transformation are difficult to discern using point-in-time analysis. Moreover, the results show that current declines in ecological conditions in the lagoon may not be reversed by changes to access rights or the emergence of co-management. Rather, these governance changes may simply help to stabilize the situation and buy time until other livelihood opportunities arise. Assessments of governance transformation thus need to be linked to ecological outcomes (i.e., reversing degradation of coastal marine systems, avoiding biophysical tipping points) which may not be easily identified in the short-term. Despite uncertainty, the emergence of policy windows, evidence of institutional innovation, and small-scale rights allocation experiments, all suggest important shifts in the trajectory of governance are underway in the Tam Giang Lagoon. 相似文献
5.
Applying marine enclosed ecosystem extensively to study the nutrient variation and its relation to biochemical process by marine ecologists and biogeologists in North America, Europe, Japan and Australia has been lasting for many years. Santschi (1982) reviewed the geochemical recirculation of nutrients systematically. Kremling et al. (1978) described the changes in nutrient in marine enclosed e- 相似文献
6.
I. P. Chubarenko N. Yu. Demchenko E. E. Esiukova O. I. Lobchuk K. V. Karmanov V. A. Pilipchuk I. A. Isachenko A. F. Kuleshov V. Ya. Chugaevich N. B. Stepanova V. A. Krechik A. V. Bagaev 《Oceanology》2017,57(5):632-638
The transition from winter vertical mixing to the formation of the spring thermocline in the southeastern Baltic Sea is studied based on data from the hydrophysical measurements program (11 expeditions) in the Russian part of Gdansk Bay in March–June 2010, 2011, and 2013. CTD measurements were taken along the standard 18-km transect across the isobaths with a 500-m step abeam the city of Baltiysk. A set of frequently measured data was collected in a 1–2 week interval from the end of March to the beginning of May, which made it possible to analyze the transformation of the vertical thermal structure of water from inverse winter type to the summer stratification with the transition of temperature over the temperature of the density maximum. Series of repeated measurements at the deep and coastal stations as well as surface and subsurface towed measurements were carried out. The fact that lenses of freshened warmer water appear at the surface almost simultaneously with intensification of cold intrusions in intermediate (10–40 m) layers makes it possible not only to confirm the advective nature of the formation of the spring thermocline in the Baltic Sea, but also to hypothesize about the intensification of intrabasin exchange when winter-time vertical mixing ceases: the potential energy excess supported by vertical mixing in the 60-m upper quasi-homogeneous layer (UQL) of the Baltic Proper, in which the horizontal estuarine salinity gradient is significant, is converted to kinetic energy of exchange currents as the mixing process terminates. Such water dynamics makes it possible to explain the intensification of intrusions in the Baltic in spring and the formation of the cold intermediate layer due to the fast propagation of late-winter UQL water from the Bornholm Basin to the Baltic Proper. The results agree well with earlier published studies of other authors. 相似文献
7.
《Marine Policy》2017
The EU Blue Growth Agenda targets maritime economic activities that have the sea and the coasts as drivers. These activities are supported by marine Ecosystem Services (ES) in combination, or not, with abiotic outputs from the marine natural capital. This paper analyses Blue Growth activities with regards to the demand and supply of marine ES and Good Environmental Status (GES). The results show that marine provisioning ES support aquaculture and blue biotechnology, while blue energy is supported by marine provisioning ES and by abiotic provisioning, and abiotic provisioning supports extraction of marine mineral resources. Maritime, coastal and cruise tourism is supported by cultural marine ES and cultural settings dependent on marine abiotic structures. All these multi-sectoral economic activities depend on healthy marine and coastal ecosystems that are provided by regulating and maintenance ES combined with the abiotic regulation and maintenance by natural marine physical structures and processes. In order to balance concurrent sectoral interests and achieve sustainable use of marine resources there is the need to consider indicators for demand for ES, which are social and economically driven, and for the supply, which are dependent on ecosystems capacity to provide the required marine ES. Some of the actions foreseeing GES are already anticipated in legislation that underpin Blue Growth, whilst others could benefit from additional regulation, particularly in what concern the exploration and exploitation of marine mineral and biological resources. Blue Growth options require navigating trade-offs between economic, social and environmental aspects. 相似文献
8.
The response of marine bacteria to mine tailings was studied in three marine ecosystem enclosures of 60 m~3, one control and two treated with 10 and 100 ppm (dry) respectively of dredged mine tailings from Alice Arm, B. C., Canada. Determination of bacterial biomass was conducted by epi-fluorescence and bacterial productivity by ~3H-thymidine uptake. During the sixteen days of the experiment, two peaks in both bacterial biomass 相似文献
9.
渔获物平均营养级(Mean trophic level of fishery landings,MTL)是目前评估人类捕捞活动影响的研究中使用最广泛的生物多样性指标之一。根据联合国粮农组织FAO提供的渔获生产统计数据,结合Fishbase提供的相关鱼种营养级数据,本文评估了1950-2010年太平洋、大西洋和印度洋各沿海国海洋渔业开发状态。研究发现,在全球三大洋75个主要捕捞国中,43个国家MTL呈显著下降趋势,发生了Pauly于1998年提出的“捕捞降低海洋食物网”现象;但是,仅16个国家MTL的下降是由于高营养级种类的衰退,而27个国家属于“捕捞沿着海洋食物网”的下降机制。此外,20个国家MTL呈恢复上升趋势,但是,该恢复上升趋势通常伴随着传统低营养级种类产量的大幅下降;在上述20个国家中,11个国家的低营养级鱼类产量呈显著下降趋势。需谨慎分析“捕捞降低海洋食物网”现象,掌握MTL的潜在变化机制。 相似文献
10.
-Six cruises were carried out off the south bank of Fujian - Taiwan during the period of December 21, 1987 to November 15, 1988 to estimate the contribution of bacterial biomass carbon (BBC) to the totai particulate organic pools using epifluorescent microscopic technique. The results show that the standing crop of bacteria fluctuated from 0. 95 to 66. 60 mg /m3 (dry weight). Upwelling phenomena appeared in the region around Nanpeng Island in summer while in the region of Waixie in all seasons. The average value of BBC was 27. 60(±6. 08)mg/m3and 21. 32 (±2. 34) mg/m3 respectively. The seasonal and spatial distribution is discussed in relation to environmental factors as well as upwelling phenomena. The role of bacteria in the flow of material and energy in the upwelling ecosystem is emphasized. 相似文献
11.
StudiesonmarinenanodiatomsinFujiancoastalwatersofChinainwinter¥LiuShicheng;GaoYahuiandChengZhaodi(ReceivedDecember22,1994;acc... 相似文献
12.
《Marine Policy》2017
The present study analysed the major features of two important acts and an ordinance in Bangladesh that govern coastal and marine fishery exploitation and conservation. The problems with the implementation of these regulations were identified, and the level of compliance among fishers and reasons for their noncompliance were assessed. Based on two case studies on coastal and marine ecosystems, the findings revealed that the level of noncompliance is highly prevalent, particularly in hilsa sanctuaries in the Meghna River estuary. The study identified coastal poverty, the inadequate and improper distribution of incentives, insufficient logistic support, limited alternative occupations, political interference and a lack of awareness regarding fishery regulations as the major limitations in the implementation. The drawbacks of proper implementation and the noncompliance of fishery regulations lead to fishery degradation, directly affect the sustainability of the coastal and marine ecosystem of Bangladesh and may be barriers to achieving Goal 14 of the Sustainable Development Goals (SDGs). Establishing a co-management mechanism for sanctuary management, creating economic opportunities outside of fishery sectors, declaring more protected areas in the coastal and marine ecosystem, enhancing logistic support to the enforcing agencies and building awareness are critical to improving the compliance level among fishers. Finally, the study submits that understanding the fishers’ reasons for compliance and noncompliance of the regulations is important for devising fishery policies through the consultation and engagement of stakeholders at all levels. 相似文献
13.
14.
Investigations on the preparation, structure and biochemical characteristics of tropomyosin (Tm) of Acetes japonicus, A. chinensis and Pseudeuphausia sinica, collected from Xiamen coastal water, show that: (1) Tm could be isolated by salting fractionation in the range of 20-35% ammonium sulphate saturation, and the contents of them are 0.86%, 0.87% and 0.70% of dry weight respectively. (2) Molecular weight of Acetes detected by SDS-PAGE method is 3.3-3.6×104, while that of P. sinica, 3.2-3.5×104. (3) Isoelectric points of all the three Tm determined by isoelectric focusing method are at about pH 5.0. (4) Crystalline spindles of above three Tm can be formed in phosphate buffer containing Mg f at pH 4.8 or pH 7.2, showing cross striations with a repeat period of 38-40 nm under the electron microscope by negative staining, and there are fine lines at irregular intervals in each striation. (5) The characteristics of the chemical composition of three Tm reveal that the strong polar amino acids account for m 相似文献
15.
A. I. Ryabinin S. A. Bobrova L. V. Saltykova E. A. Danilova 《Physical Oceanography》2012,21(5):320-328
We study the space-and-time variations of the delivery of fluxes of 26 elements (Na, K, Rb, Cs, Cu, Ag, Au, Ca, Sr, Ba, Zn,
Cd, Hg, Hf, Ta, As, Sb, Cr, Se, Mo, W, Mn, Br, Fe, Co and Ni) with atmospheric precipitations to the sea surface in the regions
of Sevastopol and the South Coast of Crimea. It is established A series of general regularities of the delivery of the sum
of these elements and their soluble and insoluble forms. We also give the characteristics of their space-time variability. 相似文献
16.
《Marine Policy》2016
In many countries, the regulation of activities and development in the marine environment has begun to evolve from a compartmentalised, fragmented, sectoral and uncoordinated system into a more strategic, comprehensive, integrated and transparent one. A remaining challenge, however, is the effective integration of marine and terrestrial planning, because the tools and mechanisms necessary for its achievement have been slow to be implemented. The introduction of the England's Coastal Concordat in 2013, as a voluntary framework for better integrating marine and terrestrial planning consents, represents an atypical mechanism to secure these goals. This paper is a preliminary survey of the perceived effectiveness of the Coastal Concordat, based on a survey of 32 professionals from the terrestrial planning authorities, marine statutory agencies and marine-sector businesses. While this evaluation is made less than two years after the introduction of the Coastal Concordat, it is important to undertake a preliminary examination, from various stakeholder perspectives, of the factors likely to be influential in the integration of regulatory systems, before the approach is ‘rolled out’ across other parts of England's inter-tidal coastal zone. The results indicate that the Coastal Concordat has produced benefits for marine planning in coastal areas, but that these improvements are largely experienced within the public sector in terms of better communication, early engagement, and a single point of contact. The marine sector businesses are more neutral about the benefits of the Concordat. It is clear, however, that marine sector businesses must participate in the formulation of any reforms if an effective integrated system of planning and management of coastal environments is to be achieved. 相似文献
17.
The formation of the fields of surface winds over the Black Sea occurs under the action of numerous physical factors. One
of the most important factors is the monsoon mechanism connected with the seasonal variations of buoyancy contrasts over the
sea and surrounding land. To separate the effects caused by this mechanism, we performed and described the numerical experiments
aimed at the evaluation of the sensitivity of the regional model of atmospheric circulation to the variations of land–sea
temperature contrasts. It is shown that the influence of these effects is restricted to the lower part of the atmosphere.
The presented estimates of the climatic fields of disturbances enable us to describe the monsoon mechanism specifying the
seasonal variability of the field of vorticity of the wind velocities and, as a consequence, the seasonal variability of the
large-scale circulation of waters in the Black Sea. 相似文献
18.
The marine geological map n. 502 “Agropoli”, located offshore the Cilento Promontory, southern Italy, is here described and the regional geology interpreted, particularly referring to water depths between the 30 and 200 m isobaths. The geologic map has been constructed in the frame of a research program financed by the National Geological Survey of Italy (CARG Project), finalized to the construction of up-to-date cartography of the Campania region. Geological and geophysical data on the continental shelf and slope offshore of the Southern Campania region have been collected in the study area, bounded northwards by the Salerno Gulf and southwards by the Policastro Gulf. A high resolution multibeam bathymetry allowed for the construction of a marine digital elevation map; sidescan sonar profiles also have been collected and interpreted. The latter, merged to the bathymetry, have represented the base for the marine geologic cartography. The integrated geologic interpretation of seismic, bathymetric and sidescan sonar data has been calibrated by sea-bottom samples. The morpho-structures and the seismic sequences overlying the outcrops of acoustic basement reported in the cartographic representation have been studied in detail using single-channel seismics. The interpretation of seismic profiles has been a support for the reconstruction of the stratigraphic and structural setting of the Quaternary continental shelf successions and the outcrops of rocky acoustic basement in correspondence to the Licosa Cape morpho-structural high. These areas result from the seaward prolongation of the stratigraphic and structural units, widely cropping out in the surrounding emerged sector of the Cilento Promontory. The cartographic approach is based on the recognition of laterally coeval depositional systems, interpreted in the frame of the system tracts of the Late Quaternary depositional sequence. We present evidence of now subaqueous terraces inferred to be palaeoshorelines representing past sea-level positions and tentatively correlated these to oxygen isotopic stratigraphy. 相似文献
19.
Karyotypes of three species of the marine Veneroida molluscs 总被引:1,自引:0,他引:1
INTRODUCTIONExceptforcorbiculalivinginfreshwater,themostVeneroidamolluscsliveinthesea .Theyarewidelydistributedwithlargequantityofcategories.Manyofthebivalvemolluscsareculturedfortheireconomicvalue .ThespeciesofSolengrandis,SaxidomuspurpuratusandMactrachinensisareaquaculturedinthenorthernseasofChina .Morphologyandcultivationbiologyofthebivalvemolluschavebeenreported (Qietal.,1 989;Weietal.,1 995;Wangetal .,1 984 ) .Asthefoundationofbivalvemollusccytogenetics ,chromosomestudyiscritical… 相似文献
20.
《Marine Policy》2013
Tropical coastal and marine social–ecological systems (CM-SESs) differ from other social–ecological systems through the higher degree of risk and uncertainty associated with coastal and marine resource extraction, the dynamic nature of aquatic and human resources, and often unclear tenure. CM-SES resource management and poverty-alleviation strategies must be adaptive and holistic. The Sustainable Livelihoods Approach (SLA) provides a framework for understanding and guiding policy-making in CM-SES. Case studies from the past 10 years analyze tropical coastal and marine-resource dependent livelihoods and/or to evaluate current CM-SES management using the SLA. These studies have shown that, despite the rounded and inclusive approach of projects such as the Sustainable Fisheries Livelihoods Programme, key challenges for researchers and practitioners remain including rights and access allocation, corruption, lack of local financial, intellectual and innovative capacity and centralized governance. Whilst the SLA may increase understanding of local-level dynamics within CM-SES, more consultation at interdisciplinary frontiers is needed in order to formulate practical solutions to the core problems of tropical CM-SES management. 相似文献