The distribution and impact of an invasive plant species (Senecio inaequidens) on a dune building engineer (Calamagrostis arenaria)

These data sets are used to run the analyses in the paper 'The distribution and impact of an invasive plant species (Senecio inaequidens) on a dune building engineer (Calamagrostis arenaria)' by Van De Walle et al., 2022, Neobiota (in progress). The presence/absence data (PA) of Senecio inaequidens in European coastal dunes can be found in 'Senecio_PA.xlsx', in the tab 'senecio_PA', together with the country and location where the occurrences were mapped. All coordinates of the samples are available in the tab 'coordinates samples'. 'Marram_growth_experiment.xlsx' contains the data gathered during the growth experiment. The origin of the sand is subdivided in 3 columns: 'Location' represents the location along the Belgian coast where sand was gathered, 'senecio' represents whether sand was gathered from underneath a senecio plant or not and 'biota' represents whether biota could affect marram grass growth (biota = 0 thus means that the sand was sterilized). Abstract Disturbance is thought to enhance the probability of invasive species establishment, a prerequisite for naturalization. Coastal dunes are characterized by disturbance in the form of sand dynamics. We studied the effect of this disturbance on the establishment and spread of an invasive plant species (Senecio inaequidens) in European coastal dunes. Local sand dynamics dictate the spatial configuration of marram grass (Calamagrostis arenaria). Therefore, marram grass configuration was used as a reliable proxy for disturbance. As marram grass plays a crucial role in natural dune formation, we evaluated the possible effects S. inaequidens could have on this process, if it would be able to naturalize in European coastal dunes. We expected the highest probability of S. inaequidens establishment at intermediate marram grass cover because too low cover would increase sand burial, whereas high cover would increase competition. However, our results indicate that S. inaequidens is quite capable of handling higher levels of sand burial. Thus, probability of S. inaequidens establishment was high under low marram cover but slightly lowered when marram cover was high, hinting at the importance of competition. We expected a negative impact of Senecio-altered soils on marram grass growth mediated by soil biota. However, marram grass grew better in sand gathered underneath Senecio plants due to abiotic soil modifications. This enhanced growth may be caused by Senecio leaf litter elevating nutrient concentrations in an otherwise nutrient-poor substrate. If such increased plant growth is a general phenomenon, further expansion of S. inaequidens could accelerate natural succession in European coastal dunes.

本数据集用于支撑Van De Walle等人2022年发表于《Neobiota》（待刊）的论文《入侵植物长舌千里光（Senecio inaequidens）对沙丘建造工程师种沙丘芦苇（Calamagrostis arenaria）的分布与影响》中的各项分析工作。长舌千里光在欧洲沿海沙丘的存在/缺失数据（PA）可于文件"Senecio_PA.xlsx"的"senecio_PA"工作表中获取，该数据同步记录了记录点所属国家与定位点位；所有样本坐标可在"coordinates samples"工作表中查阅。文件"Marram_growth_experiment.xlsx"收录了生长实验期间采集的全部相关数据。该文件中沙源信息分为三列："Location"代表沙样采集的比利时沿海沿岸点位，"senecio"代表沙样是否采集自长舌千里光植株下方，"biota"代表土壤生物群落是否会对沙丘芦苇的生长产生影响（biota=0即表示该沙样经过灭菌处理）。

摘要：干扰被认为可提升入侵物种的定殖概率，而这是入侵物种实现归化的先决条件。沿海沙丘以沙动力作用为典型干扰特征。本研究探究了该类干扰对欧洲沿海沙丘入侵植物长舌千里光定殖与扩散的影响。沙丘芦苇是调控沙丘自然形态形成的关键物种，其空间配置可作为沙丘沙动力干扰的可靠替代指标。据此，本研究同时评估了若长舌千里光在欧洲沿海沙丘成功归化，其可能对沙丘形成过程产生的潜在影响。
我们最初假设，长舌千里光的定殖概率在中等盖度的沙丘芦苇生境中最高：盖度过低会加剧沙埋胁迫，而盖度过高则会强化种间竞争。但研究结果显示，长舌千里光可较好适应高强度沙埋环境。最终数据分析表明，低盖度沙丘芦苇生境下长舌千里光的定殖概率较高，但在高盖度生境中定殖概率略有下降，这提示种间竞争在其定殖过程中发挥了重要作用。
我们曾假设经长舌千里光调控的土壤会通过土壤生物群落途径对沙丘芦苇生长产生负面影响，但实际结果却显示，采集自长舌千里光植株下方的沙样更利于沙丘芦苇生长，该效应源于非生物性的土壤改良。这种生长促进效应可能源于长舌千里光的枯落物提升了原本贫瘠基质中的养分浓度。若该生长增强效应具有普遍性，那么长舌千里光的进一步扩散或可加速欧洲沿海沙丘的自然演替进程。