The status of the world's land and marine mammals: diversity, threat, and knowledge

Knowledge of mammalian diversity is still surprisingly disparate, both regionally and taxonomically. Here, we present a comprehensive assessment of the conservation status and distribution of the world's mammals. Data, compiled by 1700+ experts, cover all 5487 species, including marine mammals. Global macroecological patterns are very different for land and marine species but suggest common mechanisms driving diversity and endemism across systems. Compared with land species, threat levels are higher among marine mammals, driven by different processes (accidental mortality and pollution, rather than habitat loss), and are spatially distinct (peaking in northern oceans, rather than in Southeast Asia). Marine mammals are also disproportionately poorly known. These data are made freely available to support further scientific developments and conservation action.     

走向卓越：从国际顶尖期刊看中国生命科学研究的发展动态

为跟踪中国生命科学领域的发展动态,以"自然指数"期刊论文为分析对象,从发文趋势、领域分布、机构贡献3个方面揭示中国生命科学研究的发展动态,研究结果表明：1）中国生命科学研究能力在持续提升,主要科技发达国家顶尖论文产出力在下降;2）中国生命科学研究形成"会聚"式发展,学科多点突破、交叉融合的趋势,CRISPR/Cas9和RNA-Seq等前沿技术得到快速应用;3）中国科学院及其直属单位集中了中国生命科学的优势科研力量,国内高校科研团队在不断成长,在个别学科领域上形成了各自的比较优势。最后,对中国生命科学研究发展存在的问题进行了讨论。     

The anatomy of the world's largest extinct rodent

Phoberomys is reported to be the largest rodent that ever existed, although it has been known only from isolated teeth and fragmentary postcranial bones. An exceptionally complete skeleton of Phoberomys pattersoni was discovered in a rich locality of fossil vertebrates in the Upper Miocene of Venezuela. Reliable body mass estimates yield approximately 700 kilograms, more than 10 times the mass of the largest living rodent, the capybara. With Phoberomys, Rodentia becomes one of the mammalian orders with the largest size range, second only to diprotodontian marsupials. Several postcranial features support an evolutionary relationship of Phoberomys with pakaranas from the South American rodent radiation. The associated fossil fauna is diverse and suggests that Phoberomys lived in marginal lagoons and wetlands.     

蜡梅栽培现状及资源保护和利用

蜡梅特产中国,是栽培历史悠久的名贵花木。蜡梅可以盆栽、地植,可切花观赏还具有药用、食用、工业用等其他经济价值。蜡梅作为著名的园林绿化树种,在我国拥有众多的品种资源优势。该文通过对蜡梅栽培生产现状研究分析,指出必须充分利用现有的资源优势、品种优势,统一认识,选育出优良品种。并对蜡梅资源保护和利用提出了发展对策。     

The mosaic genome of warm-blooded vertebrates

Most of the nuclear genome of warm-blooded vertebrates is a mosaic of very long (much greater than 200 kilobases) DNA segments, the isochores; these isochores are fairly homogeneous in base composition and belong to a small number of major classes distinguished by differences in guanine-cytosine (GC) content. The families of DNA molecules derived from such classes can be separated and used to study the genome distribution of any sequence which can be probed. This approach has revealed (i) that the distribution of genes, integrated viral sequences, and interspersed repeats is highly nonuniform in the genome, and (ii) that the base composition and ratio of CpG to GpC in both coding and noncoding sequences, as well as codon usage, mainly depend on the GC content of the isochores harboring the sequences. The compositional compartmentalization of the genome of warm-blooded vertebrates is discussed with respect to its evolutionary origin, its causes, and its effects on chromosome structure and function.     

Changing governance of the world's forests

Major features of contemporary forest governance include decentralization of forest management, logging concessions in publicly owned commercially valuable forests, and timber certification, primarily in temperate forests. Although a majority of forests continue to be owned formally by governments, the effectiveness of forest governance is increasingly independent of formal ownership. Growing and competing demands for food, biofuels, timber, and environmental services will pose severe challenges to effective forest governance in the future, especially in conjunction with the direct and indirect impacts of climate change. A greater role for community and market actors in forest governance and deeper attention to the factors that lead to effective governance, beyond ownership patterns, is necessary to address future forest governance challenges.     

凤凰单丛茶树种质资源保存及利用现状和展望

凤凰单丛是数量繁多、香型丰富的栽培型珍稀茶树种质资源,也是凤凰单丛茶产业可持续发展的关键因素。综述了凤凰单丛茶树种质资源的保存和利用现状,论述了其收集保存、鉴定评价及高效利用的研究进展,对当前保存、研究和利用的不足之处进行了分析,并针对现存问题提出今后的研究方向。     

吉林省黑土地保护现状及质量提升对策

本文阐述了吉林省黑土地保护现状，分析了吉林省黑土地质量退化问题及原因，提出了吉林省黑土地保护及质量提升对策，具体包括合理规划、转变模式、加强治理、建立机制等方面内容，以期为黑土地保护提供参考。     

Penetration of human-induced warming into the world's oceans

A warming signal has penetrated into the world's oceans over the past 40 years. The signal is complex, with a vertical structure that varies widely by ocean; it cannot be explained by natural internal climate variability or solar and volcanic forcing, but is well simulated by two anthropogenically forced climate models. We conclude that it is of human origin, a conclusion robust to observational sampling and model differences. Changes in advection combine with surface forcing to give the overall warming pattern. The implications of this study suggest that society needs to seriously consider model predictions of future climate change.     

Humans as the world's greatest evolutionary force

In addition to altering global ecology, technology and human population growth also affect evolutionary trajectories, dramatically accelerating evolutionary change in other species, especially in commercially important, pest, and disease organisms. Such changes are apparent in antibiotic and human immunodeficiency virus (HIV) resistance to drugs, plant and insect resistance to pesticides, rapid changes in invasive species, life-history change in commercial fisheries, and pest adaptation to biological engineering products. This accelerated evolution costs at least $33 billion to $50 billion a year in the United States. Slowing and controlling arms races in disease and pest management have been successful in diverse ecological and economic systems, illustrating how applied evolutionary principles can help reduce the impact of humankind on evolution.     

土地流转对农户保护性耕作投资的影响——基于四省截面数据的实证研究

在农地大规模流转背景下,采取保护性耕作技术并增加农户农地投资对于农地质量和粮食安全意义重大。基于黑龙江、河南、浙江和四川4省农户调查数据,以秸秆还田单位面积投资作为保护性耕作投资指标,采用两步法IV-Tobit模型,分析不同农地类型农户对保护性耕作投资的影响,并进一步研究影响农户对转入地投资的因素,从而探讨产权因素在保护性耕作投资决策中的作用。结果表明,样本农户的农地流转面积占比高达86.09%,发生农地流转的农户数占比也高达71.15%。土地流转契约具有以口头形式为主、约定年限短的特点。农户对保护性耕作投资仍处于低水平状态,农户在自有地上的投资略高于在转入地上的投资,多投5.25元/hm2;农户在转入地上进行秸秆还田保护性耕作投资比在自有地上少。此外,契约形式、是否约定年限、户主年龄、农户对政策了解程度、家庭劳动力数目、转出户是否要求土壤肥力保持对农户在转入地上的投资有显著的影响。基于此,提出完善土地流转机制,规范土地流转进程;做好保护性耕作的投资收益评价工作,以便为农户提供精准的农业补贴;做好政策宣传工作,增强农户保护耕地的意识等政策建议。