Biodiversity hotspots for conservation priorities

Conservationists are far from able to assist all species under threat, if only for lack of funding. This places a premium on priorities: how can we support the most species at the least cost? One way is to identify 'biodiversity hotspots' where exceptional concentrations of endemic species are undergoing exceptional loss of habitat. As many as 44% of all species of vascular plants and 35% of all species in four vertebrate groups are confined to 25 hotspots comprising only 1.4% of the land surface of the Earth. This opens the way for a 'silver bullet' strategy on the part of conservation planners, focusing on these hotspots in proportion to their share of the world's species at risk.     

Biodiversity conservation: climate change and extinction risk

Thomas et al. have carried out a useful analysis of the extinction risk from climate warming. Their overall conclusion, that a large fraction of extant species could be driven to extinction by expected climate trends over the next 50 years, is compelling: it adds to the many other reasons why new energy policies are needed to reduce the pace of warming.     

Biodiversity conservation: uncertainty in predictions of extinction risk

Thomas et al. model species-distribution responses to a range of climate-warming scenarios and use a novel application of the species-area relationship to estimate that 15-37% of modelled species in various regions of the world will be committed to extinction by 2050. Although we acknowledge the efforts that they make to measure the uncertainties associated with different climate scenarios, species' dispersal abilities and z values (predictions ranged from 5.6% to 78.6% extinctions), we find that two additional sources of uncertainty may substantially increase the variability in predictions.     

Biodiversity: invasions by marine life on plastic debris

Colonization by alien species poses one of the greatest threats to global biodiversity. Here I investigate the colonization by marine organisms of drift debris deposited on the shores of 30 remote islands from the Arctic to the Antarctic (across all oceans) and find that human litter more than doubles the rafting opportunities for biota, particularly at high latitudes. Although the poles may be protected from invasion by freezing sea surface temperatures, these may be under threat as the fastest-warming areas anywhere are at these latitudes.     

Biodiversity conservation: effects of changes in climate and land use

Thomas et al. argue, contrary to Sala et al. that climate change poses an equal or greater threat to global biodiversity than land-use change. We contest this claim, however, on the grounds that Thomas et al. incorrectly apply species-area relationships.     

深度学习在海洋大数据挖掘中的应用

 介绍了深度学习的关键发展节点和应用发展历程,分析了深度学习在国内外主要领域的发展现状;概述了多个深度学习的关键算法原理,分析了深度学习在海洋数据重构、分类识别和预测等海洋大数据挖掘中的相关应用;提出了深度学习未来可能面临的问题,并从加强顶层设计、信息安全和强化算法鲁棒性等方面,展望了深度学习在海洋大数据挖掘中的应用前景。     

开源大数据框架在海洋信息处理中的应用

 随着中国海洋观测技术和数据收集手段的发展,海洋观测数据量日益庞大、数据复杂程度逐渐增多,传统的数据存储方式和处理方法无法有效地对海洋数据进行管理和分析,同时,数据的区域化和分布化成为海洋数据统一管理的一个障碍,对海洋数据挖掘造成一定困难。本文从大数据生命周期的维度,介绍了主流开源大数据框架在海洋大数据获取、存储、处理、智能分析、安全保护和治理方面的技术原理和应用。     

大开口对船舶板架稳定性和极限承载力的影响

选取典型船舶板架，采用ANSYS系统，对开口和不开口的板，分别进行了特征值屈曲分析和极限承压屈曲分析，同时，运用便于简化处理的相当梁系法，将加筋板架，近似看作由带附连翼板的交叉梁系构成，转换以后，给出了一套工程近似计算方法，经分析比较，得知：板的屈曲模式所对应的屈曲压力并不一定是最低的，高应力区出现了梁（桁）腹板平面外的失稳，大开口边缘构件的倾向刚度大大削弱，纵桁的理论论界应力降低。