Morphometric, taxonomic, and functional trait data of deep-sea nematodes from a colonisation experiment simulating organic matter deposition at HAUSGARTEN (Fram Strait)

This dataset contains individual-based morphometric, taxonomic, and functional trait data of deep-sea nematodes collected during a colonisation experiment conducted at the long-term observatory HAUSGARTEN in the Fram Strait (Arctic Ocean). The experiment aimed to investigate the colonisation dynamics and trait-based responses of nematode communities to different qualities of organic matter input in artificially prepared deep-sea sediments.

During the RV Polarstern expedition PS85 (June 2014), a bottom lander was deployed at 1265 m water depth near HAUSGARTEN station HG-I (79°8.69'N, 6°8.23'E). The lander carried twelve colonisation cores filled with azoic, artificial sediments and exposed for three months on the seafloor. Three treatments were applied, each with four replicate cores: (1) enrichment with fresh Phaeocystis (FP), (2) enrichment with decayed Phaeocystis (DP), and (3) unenriched control cores. This design simulated the effect of phytodetritus deposition in different degradation states on early colonisers within benthic communities.

As a natural reference, sediment samples were taken from undisturbed seafloor using a multiple corer (MUC) at 1244 m depth at the same station (79°8.01'N, 6°6.39'E). For both the artificial colonisation cores and natural MUC samples, subsampling was conducted using 2.2 cm diameter cut-off syringes. From each core, the upper 3 cm of sediment were collected, sliced into 1 cm layers, and fixed in 4% borax-buffered formalin prepared with filtered seawater.

Individual nematodes were identified to genus level. Body length and width were measured, and biomass (µg dry weight) was calculated. Each genus was assigned a feeding type based on Wieser (1953) and a coloniser–persister (c–p) value following Bongers (1990) and Bongers et al. (1995), providing insight into their trophic role and life-history strategy.

This dataset enables comparative analysis of nematode traits under controlled experimental enrichment versus natural background conditions, and contributes to a better understanding of benthic ecosystem responses to variable organic matter input in Arctic deep-sea environments.

本数据集收录了北冰洋弗拉姆海峡（Fram Strait）长期观测站HAUSGARTEN开展的定殖实验中采集的深海线虫个体水平形态计量学、分类学与功能性状数据。本实验旨在探究人工制备深海沉积物内，线虫群落的定殖动态及其基于性状的响应模式，以解析不同品质有机质输入对其的影响。
在极星号（RV Polarstern）PS85科考航次（2014年6月）期间，研究人员于HAUSGARTEN站HG-I附近（79°8.69'N，6°8.23'E）的1265米水深海域布放海底着陆器。该着陆器搭载12个定殖培养柱，柱内填充无菌人工沉积物，并在海底原位放置3个月。实验设置3种处理组，每组含4个重复培养柱：(1) 新鲜普林藻（Phaeocystis, FP）富集组，(2) 腐解普林藻（Phaeocystis, DP）富集组，(3) 未富集对照组。该实验设计模拟了不同降解状态的植物碎屑沉降对底栖群落早期定殖者的影响。
为设置自然参照组，研究人员在同一站位（79°8.01'N，6°6.39'E）的1244米水深海域，使用多管采泥器（multiple corer, MUC）采集未受扰动的海底沉积物样品。针对人工定殖培养柱与自然MUC沉积物样品，研究人员均采用直径2.2 cm的截口注射器进行分样。从每个培养柱中采集表层3 cm沉积物，切割为1 cm厚度的分层样品，随后使用经过滤海水配制的4%硼砂缓冲福尔马林溶液固定。
研究人员将单个线虫鉴定至属级水平，测量其体长与体宽，并计算生物量（单位：微克干重）。基于Wieser（1953）的取食类型分类标准为每个属赋予对应取食类型，参照Bongers（1990）及Bongers等（1995）提出的定殖-持久（coloniser–persister, c-p）分级标准赋值，以此揭示其营养生态位与生活史策略。
本数据集支持受控实验富集条件与自然背景条件下线虫性状的对比分析，有助于深入理解北极深海底栖生态系统对动态有机质输入的响应机制。