Habitat isolation interacts with top-down and bottom-up processes in a seagrass ecosystem

Habitat loss is accelerating at unprecedented rates, leading to the emergence of smaller, more isolated habitat remnants. Habitat isolation adversely affects many ecological processes independently, but little is known about how habitat isolation may interact with ecosystem processes such as top-down (consumer-driven) and bottom-up (resource-driven) effects. To investigate the interactive influence of habitat isolation, resource availability and consumer distribution and impact on community structure, we tested two hypotheses using invertebrate and algal epibionts on temperate seagrasses, an ecosystem of ecological and conservation importance. First, we hypothesized that habitat isolation will change the structure of the seagrass epibiont community, and isolated patches of seagrass will have lower epibiont biomass and different epibiont community composition. Second, we hypothesized that habitat isolation would mediate top-down (i.e., herbivory) and bottom-up (i.e., nutrient enrichment)..., This data was collected using natural and artificial seagrass units. The epibionts on the seagrass blades were identified, enumerated, and incinerated for ash free dry weight., Excel, Google Sheets生境丧失正以前所未有的速度加剧，由此形成了规模更小、隔离程度更高的生境残余斑块。生境隔离可独立对诸多生态过程产生负面影响，但目前对生境隔离如何与自上而下（消费者驱动）、自下而上（资源驱动）等生态系统过程产生交互作用仍缺乏深入认知。为探究生境隔离、资源可获得性、消费者分布及其对群落结构的交互影响，本研究以兼具生态与保护价值的温带海草床生态系统为研究载体，选取其上的无脊椎动物与藻类附生生物（epibionts）为研究对象，验证了两项假说：其一，生境隔离会改变海草附生生物群落结构，隔离的海草斑块的附生生物生物量更低，且群落组成存在显著差异；其二，生境隔离会对自上而下（即牧食作用）与自下而上（即养分富集）效应产生调控作用……本数据集通过自然与人工海草单元采集获得。研究人员对海草叶片上的附生生物进行了种类鉴定、个体计数，并通过灼烧法测定其无灰干重。数据文件格式为Excel、Google Sheets。