The energetic assembly of biological communities: a test with deep-sea woodfalls

气候变化下陆地和海洋碳生产量的变化需要了解生态群落是如何由碳的可获得性构成的，这一点长期以来一直被认为是生物多样性的预测指标。最近的研究表明，全球海洋浮游植物产量可能以每年全球中位数的约1%的速度下降。区域范围的变化更加不均；赤道太平洋在过去十年中总体下降了50%以上，极地地区则出现了相当幅度的增长。显然，迫切需要更全面地了解生物多样性和碳可获得性之间的关系，以便更好地预测当前和即将发生的气候变化对海洋生态系统的影响。一个挑战是，自然系统中可用碳的决定因素是多样的，而且往往无法识别。深海林木群落是检验许多关于碳有效性和生物多样性理论的理想实验系统。首先，社区可获得的碳量可以精确地以木材质量的形式进行控制。其次，从木头流过群落的碳很容易被追踪，因为由木头支撑的动物有明显的化学特征，可以通过稳定的同位素分析进行追踪。最后，可以对与林木坠落相关的整个群落进行采样，从而准确地估计生物多样性、生物量和能量流。出于这些原因，对深海林木瀑布的研究提供了作为能量可获得性的函数的现存量、多样性和营养结构的准确和同步的量化。通过使用水下机器人/潜水式木瀑布，该项目将测试碳可获得性的变化如何影响海洋生物多样性。这个项目的结果将在几个方面对科学有益。首先，该项目对气候变化和生物多样性研究，特别是对未充分开发的深海的认识作出了重大贡献。该项目还为公众宣传创造了大量机会。这种多方面的方法包括：使用网络播客和博客；通过摄影展分享成果；积极从为少数群体服务的机构招聘，同时还提供访问讲师机会。此外，该项目将在代表性不足的群体中招聘和培训年轻科学家，并影响到来自小学教育学生、科学教师和普通公众的多个受众。该项目的目标是利用ROV/潜水式铺设的木材瀑布，确定调节社区结构的能量过程中的相互作用。木材将以不同的大小部署，以控制添加到社区的化学能的数量，并以不同的木材密度来检查组装规则，同时检查资源的总量和集中度。这种方法将允许研究人员检查能量权衡，即可以同时评估不同碳可获得性对生物多样性的多种影响、假设和理论。群落中的碳量可以被精确地操纵，这比之前的研究有所改进。碳吸收速度对生态过程的影响也将在这里进行研究，但很少被评估。这项研究还将揭示深海中的森林生物群，这是海洋中研究最少的系统之一。例如，该项目将揭示不同的碳途径在输出木材能源和控制生物多样性方面的相对重要性。

Changes in both terrestrial and marine carbon production under climate change necessitate an understanding of how ecological communities are structured by carbon availability, which has long been recognized as a predictor of biodiversity. Recent research indicates global marine phytoplankton production may have declined at a rate of ~1% of the global median per year. Regional-scale changes have been more heterogeneous; with the equatorial Pacific Ocean experiencing overall declines of over 50% the last decade and Polar Regions experiencing increases of comparable magnitude. Clearly, there is a strong need for a more complete understanding of the relationship between biodiversity and carbon availability to better predict the consequences of current and forthcoming climate change on marine ecosystems. One challenge is that determinants of available carbon in natural systems are diverse and often unidentifiable. Wood-fall communities in the deep sea are an ideal experimental system for testing many theories about carbon availability and biodiversity. First, the amount of carbon available to the community can be precisely manipulated in the form of wood mass. Second, flows of carbon from wood through the community can be easily tracked because animals supported by wood have distinct chemical signatures that can be traced with stable isotope analysis. Finally, the entire community associated with a wood fall can be sampled, allowing for accurate estimates of biodiversity, biomass, and energy flow. For these reasons, study of deep-sea wood falls provides accurate and simultaneous quantification of standing stock, diversity, and trophic structure as a function of energy availability. Through the use of ROV/submersible-deployed wood falls, the project will test how changes in carbon availability impact marine biodiversity. The results of this project will be beneficial to science in several ways. First, the project contributes significantly to climate change and biodiversity research and specifically to knowledge of the underexplored deep oceans. The project also creates abundant opportunities for public outreach. The multifaceted approach includes: employing web podcasts and blogs; sharing results through photographic exhibitions; and actively recruiting from minority-serving institutions while also providing visiting lectureships. Further, the project will recruit and train young scientists in underrepresented groups, and impact multiple audiences from primary education students, science instructors, and the general public. The goal of this project is to identify the interactions in energetic processes that regulate community structure, using ROV/submersible-deployed wood falls. Wood will be deployed in varying sizes to control the amount of chemical energy added to the community, and of different wood densities to examine assembly rules while examining total quantity and concentration of resources. This approach will allow the investigators to examining energetic tradeoffs is that multiple impacts, hypotheses, and theories of varying carbon availability on biodiversity can be evaluated simultaneously. The amount of carbon in the community can be precisely manipulated, an improvement over prior studies. The impact of the rate of carbon uptake on ecological processes will also be examined here, but has been rarely evaluated. This research will also reveal much about wood-fall biomes in the deep sea, one of the least studied systems in the ocean. For example, the project will reveal the relative importance different carbon pathways in exporting wood energy and controlling biodiversity.