Collaborative research: Biodiversity and ecosystem functioning in plant-grazer systems: experimental tests in a marine benthic community

维持生物多样性及其所依赖的生态系统进程是保护生物学的主要目标，也是社会高度关注的问题。对陆地生境的有影响力的研究表明，几个生态系统过程与植物多样性有关。然而，在海洋生态系统中，对植物多样性和功能之间的联系的研究仍然很少。此外，消费者在调节初级生产和社区结构方面发挥中心作用，特别是在海洋中。但消费者多样性在调节植物多样性和生产关系以及其他重要生态系统过程中的重要性，对任何系统都知之甚少。随着人类对海洋生物栖息地的干扰越来越大，前所未有的灭绝的可能性越来越大，迫切需要了解海洋动植物的特性和多样性的功能作用。这项研究项目将在北卡罗来纳州的中观和野外实验中，使用不同的海洋大型藻类及其草食动物组合来解决上述问题，包括端足类、等足类、腹足类、海胆、螃蟹和鱼类。对藻类和消费者的特性和多样性以及资源的可获得性(即营养和光照)进行因子处理，将检验这些因素对初级和次级生产力以及个人和整个社区消费率的相对独立和相互作用的影响。这个系统的几个特点使它特别容易进行这项研究，包括对其自然历史和生态的详细了解。具体而言，本项目将解决以下五个问题：1)藻类特性和多样性如何影响净初级生产力；2)藻类特性和多样性如何影响个体和整体？群落消耗率和二次生产量？3)消费者身份和多样性如何影响净初级生产力？4)植物和草食动物特性和多样性在控制净初级生产力方面有哪些相对独立和相互作用的影响？5)植物多样性和草食性如何与资源可获得性相互作用以控制净初级生产力？这些相互作用的因素的相对重要性是什么？这将是通过海洋群落的野外操作来测试物种多样性对生态系统属性的影响的首批研究之一，也是少数几项在析因设计中同时考虑猎物和消费者多样性的作用的研究之一。在这样做的过程中，这项研究将直接测试植物多样性对生态系统过程的广泛宣传的影响是如何通过现实的消费者压力水平改变的。这项研究计划还汇集了三位在实验底栖海洋生态学、恢复和景观生态学以及大型植物、鱼类和无脊椎动物生物学方面具有互补优势的主要研究人员。这项研究符合NSF生物海洋学计划重点的海洋系统生物多样性专题。这一结果将帮助生态学家和政策制定者了解物种多样性持续丧失的潜在后果，通过帮助明智地保护类似的系统，潜在地使社会受益。此外，该项目将对教育和培训产生更广泛的影响，为各种教育水平(从本科生到博士后科学家)和背景的青年科学家提供研究机会，包括在科学界代表性不足的群体。结果将通过顶级期刊上的出版物传播，并通过非技术杂志上的文章、我们的网站和公共研讨会向公众传播。

The maintenance of biological diversity and the ecosystem processes dependent on it are key goals of conservation biology and are issues of great societal concern. Influential research in terrestrial habitats has shown that several ecosystem processes are related to plant diversity. Yet links between plant diversity and function remain poorly studied in marine ecosystems. Moreover, consumers play central roles in regulating primary production and community structure, particularly in the oceans. But the importance of consumer diversity in mediating plant diversity and production relationships as well as other important ecosystem processes is poorly known for any system. With increasing human perturbation of marine habitats and the growing likelihood of unprecedented extinctions, there is a pressing need to understand the functional roles of the identity and diversity of marine plants and animals. This research project will address the foregoing issues using a diverse assemblage of marine macroalgae and their herbivores, including amphipods, isopods, gastropods, urchins, crabs, and fish, in mesocosm and field experiments in North Carolina. Factorial manipulations of algal and consumer identity and diversity, as well as resource availability (i.e., nutrients and light), will test the relative independent and interactive effects of these factors on primary and secondary productivity, and individual and community?wide consumption rates. Several characteristics of this system make it exceptionally tractable for this study, including a detailed understanding of its natural history and ecology. Specifically, this project will address the following five questions: 1) How do algal identity and diversity affect net primary production? 2) How do algal identity and diversity affect individual and whole?community consumption rates and secondary production? 3) How do consumer identity and diversity affect net primary production? 4) What are the relative independent and interactive effects of plant and herbivore identity and diversity in controlling net primary production? 5) How do plant diversity and herbivory interact with resource availability to control net primary production? What is the relative importance of these interacting factors?This will be one of the first studies to test the effects of species diversity on ecosystem properties using field manipulations in a marine community, and one of the few studies in any system to consider simultaneously the roles of prey and consumer diversity in a factorial design. In doing so this research will directly test how the widely publicized effects of plant diversity on ecosystem processes are altered through realistic levels of consumer pressure. This research program also brings together three principle investigators with complementary strengths in experimental benthic marine ecology, restoration and landscape ecology, and specializations in macrophyte, fish, and invertebrate biology. The research fits within the Biological Diversity in Marine Systems special theme of emphasis of the NSF Biological Oceanography Program. The results will help ecologists and policy makers understand the potential consequences of the ongoing loss of species diversity, potentially benefiting society by helping to wisely conserve similar systems. In addition, this project will have broader impacts in education and training by providing research opportunities to young scientists at a range of educational levels (from undergraduate to postdoctoral scientists) and backgrounds, including groups that are underrepresented in science. Results will be disseminated through publications in top journals, and to the general public through articles in non?technical magazines, our web sites, and public seminars.