Modeling expert judgment to assess cost-effectiveness of EU Marine Strategy Framework Directive programs of measures     

《Marine Policy》2015

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Understanding socio-ecological drivers of spatial allocation choice in a multi-species artisanal fishery: A Bayesian network modeling approach     

《Marine Policy》2015

Effective management of artisanal fisheries requires understanding fishers, their behaviors, and the drivers that underpin their choices. Behavioral drivers are critical links in understanding the interactions between social and ecological systems and can help inform effective management approaches. A Bayesian Belief Network modeling approach was used to investigate a diverse range of qualitative and quantitative social and ecological drivers of spatial location choice in a multi-species artisanal dive fishery in Costa Rica. Empirical and observer data used to populate the BBN showed the influence of economic factors, environmental conditions as well as social interactions on the decision-making process of spatial location choice. Good governance scenarios represented by Responsible Fisheries Marine Areas Management were analyzed for both hookah and free diving methods to assess the effects of responsible fishing on the fishers and the fishery. Model based-scenario analysis suggests that management interventions should consider the fisher's potential behavioral responses in the context of environmental variability, dependence on cultural assets, and food security. The results show that there is a need to understand fisher's decisions based on broad socio-ecological system understanding and consider the environmental outcomes alongside food security and the cultural significance of different marine species to fishing communities.  相似文献   

基于ArcEngine的海域定级系统的设计与实现     

程敏  张秀英  陈书林  卢学鹤  钟太洋 《海洋科学》2015,39(6):88-93

海域定级是采用定性和定量的方法将同一类型用海划分为不同级别,是海域管理最基础性的工作,对于科学合理地开发和利用海岸带资源至关重要。本研究以Visual Studio 2010为开发平台,采用C语言,结合嵌入式ArcEngine组件库,集成设计实现海洋领域具有较高专业性和实用性的海域定级系统。该系统采用海洋公益领域专家制定的指标体系,通过数据的管理、集成和分析,实现了海域定级相关方面的功能。该系统将海域定级原理与地理信息系统(Geographic Information System,GIS)技术相结合,为海域基层部门提高工作效率、实现海岸带资源科学有效管理提供了依据。  相似文献   

Long‐term comparison of structure and dynamics of the red coral metapopulation of the Portofino Promontory (Ligurian Sea): a case‐study for a Marine Protected Area in the Mediterranean Sea          下载免费PDF全文

Giorgio Bavestrello  Marzia Bo  Marco Bertolino  Federico Betti  Riccardo Cattaneo‐Vietti 《Marine Ecology》2015,36(4):1354-1363

A large amount of data on the precious coral Corallium rubrum has attested to a dramatic shift in the size structure of its over‐harvested Mediterranean populations in recent decades. One of the main problems for the conservation of this species is the substantial lack of data concerning the time span necessary for a population subjected to pluri‐decennial harvesting pressure to return to its pristine status. Here, we present a multi‐annual data set gathered from the Marine Protected Area (MPA) of Portofino, which hosts the most important shallow‐water coral populations in the Ligurian Sea and was subjected to strong harvesting pressure from the 1950s to the early 1970s. Quantitative comparison of the population structure data recorded in 1964, 1990 and 2012 indicated a strong size increase of the colonies (from 3 to 8 g mean weight), resulting in an increase in colony biomass from 300 to the current 1500 g·m^?2. As a consequence, over the same span of time, the density of colonies has slightly decreased. The role of mass mortality phenomena, like that occurred in this area during 1999, as possible biological features triggering the switch of red coral populations from a ‘grass plain‐like’ towards a ‘forest‐like’ structure, is discussed. All these data indicate that the instigation of MPAs is a winning strategy in the conservation of this precious species and similar management plans should also be evaluated for the protection of the deep benthic communities thriving on off‐shore banks.  相似文献   

精密单点定位在国土调查正射影像底图生产中的应用研究     

张德成  常军  程小凯  方征  杨盼 《测绘与空间地理信息》2021,44(4):20-23

精密单点定位技术作为一种快速获取像控点坐标的方法,不需要同步联测,可在大面积正射影像生产中发挥重要作用。通过对不同时段长度观测数据的精密单点定位和ITRF2014框架瞬时历元坐标向CGCS2000坐标转换两个方面的探讨,分析了精密单点定位技术进行像控点测量并实现正射影像生产的关键问题。结果表明:以60 min观测时长数据进行精密单点定位,并利用框架转换参数和格网速度场实现像控点CGCS2000坐标获取的最大点位误差为0.38 m,可以满足国土调查1∶10 000比例尺正射影像底图生产像控点测量精度要求。  相似文献   

The youngest record of metriorhynchid crocodylomorphs,with implications for the extinction of Thalattosuchia     

《Cretaceous Research》2015

Here we describe an isolated tooth of a metriorhynchid crocodylomorph from the Hybla Formation (Aptian, Lower Cretaceous) of Rocca Chi Parra quarry (Montagna Grande, Calatafimi, Trapani Province), Sicily, Italy. The specimen shares with the Upper Jurassic taxon Plesiosuchus manselii a mediolaterally compressed conical tooth crown, noticeable lingual curvature, mesial and distal carinae with microscopic, rectangular contiguous denticles, strong distal curvature of the mesial margin, and the presence of weak 'carinal flanges' on the labial and lingual surfaces (which are preeminent at the mid-crown). This suite of morphologies is also present in an unnamed Valanginian (Lower Cretaceous) plesiosuchinan from France. However, the Sicilian tooth differs from these taxa in having more pronounced carinae, and faint apicobasally aligned enamel ridges. It also differs from P. manselii in having more extensive 'carinal flanges' on the labial surface. The specimen extends the known geological range of Metriorhynchidae and Thalattosuchia by approximately 7–8 million years. This overturns previous hypotheses of Metriorhynchidae becoming extinct early in the Early Cretaceous.  相似文献   

The geochemistry of platinum group elements in marine oil shale—A case study from the Bilong Co oil shale,northern Tibet,China     

《Chemie der Erde / Geochemistry》2015,75(1):55-63

The Bilong Co oil shale zone is located in the South Qiangtang depression. This zone, together with the Shengli River-Changshe Mountain oil shale zone in the North Qiangtang depression, northern Tibet plateau, represents the potentially largest marine oil shale resource in China. Seventeen samples including oil shale and micritic limestone were collected from the Bilong Co oil shale area to determine the concentrations, distribution patterns, occurrences and origins of platinum group elements (PGEs) in marine oil shale. The oil shale samples from the Bilong Co area exhibit very low total PGE contents ranging from 1.04 to 2.96 ng/g with a weighted mean value of 1.686 ng/g, while the micritic limestone samples from the Bilong Co area exhibit a little lower PGE value ranging from 0.413 to 1.11 ng/g. PGEs in oil shale samples are characterized by high contents in Pd (average 0.79 ng/g), Os (average 0.123 ng/g) and Pt (average 0.644 ng/g) compared with Ru (average 0.068 ng/g), Rh (average 0.033 ng/g) and Ir (average 0.026 ng/g). The highest values for individual PGEs are not uniformly distributed in the section. Clearly, the PGEs are generally enriched in the oil shale samples near the boundary between micritic limestone and oil shale.The individual PGEs in oil shale samples from the Bilong Co area exhibit various modes of occurrence. Ruthenium and Pt occur mainly in pyrite, while Pd is associated mainly with organic matter and Mg-minerals. Rhodium and Os are controlled mainly by pyrite and organic matter. Iridium is present mainly in other Fe-bearing minerals, rather than pyrite. The PGEs in the Bilong Co oil shale are mainly of seawater origin and possibly influenced by terrigenous supply.  相似文献   

Applications of Intact Polar Lipids for Tracing the Marine Microbial Activity and Their Limitations     

Song Min  Yang Qunhui  Wang Hua  Ji Fuwu  Wang Hu  Pan Anyang  Zhou Huaiyang 《地球科学进展》2015,30(10):1162-1171

Intact Polar Lipids (IPLs) are synthesized predominately or uniquely by specific organisms and would degrade rapidly after cell death. Such biomarker IPLs can be used to indicate the microbial distribution and activity in marine environment. Here the progress of the aforementioned studies made over the last decade was reviewed. With the development of chromatography and mass spectrometry, the discovery of new IPLs compounds and the application of stable carbon isotope composition (δ¹³C) of IPLs, our understanding of the composition and transformation of IPLs in suspended particulate matter in the water column and of the applicability of the TEX₈₆ proxy are greatly improved. Besides, IPLs are widely applied in the study of marine eukaryotes-bacteria symbiosis, aerobic and anaerobic ammonia oxidation, anaerobic methane oxidation and microbial metabolic states. Meanwhile, it is suggested by recent studies that different IPLs often exhibit differential degradation. Some IPLs, especially glycolipids, have the potential to be preserved as fossil molecules for very long time upon dead cells, and therefore, they can not specifically indicate living biomass. Furthermore, the IPLs degradation rate and completeness would be affected by such factors as oxygen concentration and organic matter content. It is also suggested that the composition of IPLs might be affected by microbial metabolism. Therefore, it is essential to take these factors into account when IPLs are used as proxies to trace marine microbial activities and reconstruct the palaeoenvironment.  相似文献   

一次江淮气旋的模拟和海洋敏感试验   总被引：3，自引：2，他引：1  

徐迎春  魏建苏  朱伟军 《气象科学》2011,31(6):726-731

运用中尺度WRFV3.0模式,对2009年4月19日00时-22日00时期间的一次江淮气旋进行了数值模拟(控制试验CTR)研究,得出在CTR中江淮气旋的路径和发展趋势总体上比较理想,为此进一步设计海洋属性敏感试验,探讨海洋属性对江淮气旋的路径和强度的影响.结果表明:当海洋属性修改成陆地属性后,江淮气旋路径向东南偏移,入海后,偏离程度增大;气旋强度在大别山附近稍有增强,入海后强度减弱.气旋中心南侧的偏南气流、气旋前部的水汽辐合区和强对流有效位能,以及气旋中心附近的强潜热能,均有利于江淮气旋发展.  相似文献   

The abundance, composition and sources of marine debris in coastal seawaters or beaches around the northern South China Sea (China)   总被引：4，自引：0，他引：4  

Peng Zhou  Chuguang Huang  Hongda Fang  Weixu Cai  Dongmei Li  Xiaomin Li  Hansheng Yu 《Marine pollution bulletin》2011,62(9):1998-2007

The abundance and composition of marine debris including floating marine debris (FMD), seafloor marine debris (SMD) and beached marine debris (BMD) were investigated in coastal seawaters/beaches around the northern South China Sea during 2009 and 2010. The FMD density was 4.947 (0.282-16.891) items/km², with plastics (44.9%) and Styrofoam (23.2%) dominating. More than 99.0% of FMD was small or medium size floating marine debris. The SMD and BMD densities of were 0.693 (0.147-5.000) and 32.82 (2.83-375.00) items/km², respectively. SMD was composed of plastics (47.0%), wood (15.2%), fabric/fiber (13.6%) and glass (12.1%), while BMD was composed of plastics (42.0%) and wood (33.7%). More than 90% of FMD, 75% of SMD and 95% of BMD were not ocean-based sources but land-based sources, mostly attributed to coastal/recreational activity, because of the effect of human activities in the areas.  相似文献