The interaction between bottom-up and top-down processes in coastal ecosystems has been scarcely studied so far. Temporal changes in trophic interactions of Zostera marina along the Swedish west coast are relatively well studied, with the exception of epifaunal communities. Epifauna was used as a model study to explore resource (bottom-up) or predator (top-down) regulated in a vegetated ecosystem. We conducted a 21-year comparative study (1997 and 2018) using epifauna of 19 Zostera marina meadows along the Swedish Skagerrak coast. Large changes were observed in the composition of small (0.2–1 mm) and large (>1 mm) epifauna. In the small-sized epifauna, the nematode Southernia zosterae and harpacticoids showed an increase of 90% and a decrease of 50% of their abundances, respectively. In the large-sized epifauna, the polychaete Platynereis dumerilii and chironomid larvae were absent in 1997 but thrived in 2018 (>2000 ind. m⁻²). Mesoherbivores (Idoteids and gammarids) were locally very abundant in 1997 but disappeared in 2018. An 83% decline of mytilids settling in Zostera marina leaves was observed. Our results showed that epifauna is predominantly top-down regulated. An integrative framework of the study area is outlined to shed light on the causes and consequences of the environmental shifts reported in Zostera meadows from the northern Skagerrak area throughout the last three decades.

到目前为止，几乎没有研究过沿海生态系统中自下而上和自上而下过程之间的相互作用。除表生动物群落外，沿瑞典西海岸的Zostera滨海的营养相互作用的时间变化已得到相对较好的研究。Epifauna被用作模型研究，以探索在植被生态系统中受到调节的资源（自下而上）或捕食者（自上而下）。我们对瑞典Skagerrak海岸沿岸的19个Zostera滨海草地进行了21年的比较研究（1997年和2018年）。小型（0.2–1 mm）和大型（> 1 mm）表生动物的组成变化很大。在小型表生动物中，线虫Southernia zosterae类和类拟螺类动物的丰度分别增加了90％和减少了50％。在大型表生动物中，1997年不存在多毛Pla侧柏（Platynereis dumerilii）和and虫（chironomid）幼虫，但在2018年则蓬勃发展（> 2000 ind。m ^-2）。Mesoherbivores（同型异位体和γ-异位体）在1997年在当地非常丰富，但在2018年消失了。观察到Zostera滨海叶片中沉降下来的Mytilids下降了83％。我们的结果表明，表生动物主要受自顶向下的调节。概述了研究区域的综合框架，以阐明过去三十年来从北部Skagerrak地区Zostera草甸报道的环境变化的原因和后果。