Mechanical traits as drivers of trophic interaction between macrodetritivores and leaf litter

In ecosystems, the rates of resource consumption by animals drive the flows of matter and energy. Consumption rates are known to vary according to consumer energy requirements, resource nutrient content and mechanical properties. The aim of our study is to determine how mechanical constraints, compared to energetic and nutritional constraints, explain the variation in leaf litter consumption rates by macrodetritivores. In particular, we focus on the impact of litter toughness. To this end, we propose a non-linear model describing leaf litter consumption rates of detritivore as a function of litter toughness. We also investigate a possible match between bite force and litter toughness, since consumer-resource co-occurrence is thought to be driven by the match between invertebrate mandibular traits and resource toughness. Our study was designed as follows: leaf litter from oak and hornbeam was exposed to field physical and microbial decomposition in aquatic and terrestrial ecosystems for ..., Sites and experimental design Our sampling sites were located south of Toulouse (France), in the Pyrenean Piedmont, an area characterized by a calcareous bedrock and continental climate. Leaf litter and detritivores were collected in oak-hornbeam forests. For each ecosystem type (low order streams and forest floors), we selected two sites, one dominated by oak (Quercus petraea) and the other by hornbeam (Carpinus betulus). Hornbeam sites were both located in a hornbeam coppice stand. The terrestrial oak site was a mature even-aged oak forest. As there was no stream crossing it, we selected a nearby stream running along a forest edge dominated by oak trees. Leaf litter was collected at the time of abscission and stored air-dried at room temperature. Leaf litter was also collected later, after various physical and microbial decomposition times, to produce litter with varying toughness values. In our feeding experiments, detritivore individuals collected at a site were only offered the loc..., , # Mechanical traits as drivers of trophic interaction between macrodetritivores and leaf litter [https://doi.org/10.5061/dryad.ngf1vhj2j](https://doi.org/10.5061/dryad.ngf1vhj2j) This table is the result of consumption tests aiming to quantify the consuption rate of leaf litter by different detritivore taxa. Leaf litter (Hornbeam or Oak) was left to decompose in a forest stream or on a forested soil and collected (after 0 to 349 days). Detritivores comprise 3 aquatic and 5 terrestrial taxa. Consumption rates were measured at the laboratory in microcosms. We performed controls with leaf litter discs without detritivores to correct consumption rates. We measured the mean litter toughness, softness, CN ratio, and N percent content for each litter batch. We measured a mean index for detritivore mandible strength for each detritivore taxon. We measured or estimated (from individual fresh body mass) each individual dry body mass. ## Description of each data column * Ecosystem: A=aqua...在生态系统中，动物的资源消耗速率驱动着物质与能量的流动。已知动物的资源消耗速率会随其自身能量需求、资源的营养组分以及力学特性发生变化。本研究旨在明确：相较于能量与营养限制，力学限制如何解释大型碎屑食性动物（macrodetritivores）对枯落叶的消耗速率变异，尤其聚焦于枯落叶韧性的影响。为此，我们构建了一个非线性模型，用以描述碎屑食性动物的枯落叶消耗速率随枯落叶韧性的变化关系。此外，我们还探讨了咬合力与枯落叶韧性之间的潜在匹配性——已有研究表明，无脊椎动物的颚部性状与资源韧性的匹配关系，是驱动消费者与资源共存的关键机制。 本研究的实施流程如下：采集自栎树与鹅耳枥的枯落叶，分别在水生与陆生生态系统中开展野外物理与微生物分解…… ### 采样点与实验设计 本研究的采样点位设置于法国图卢兹以南的比利牛斯山麓地带，该区域以石灰岩基床与大陆性气候为典型特征。枯落叶与碎屑食性动物均采集自栎-鹅耳枥混交林。针对两种生态系统类型（低等级溪流与森林地表），我们各选取两个采样点：一个以夏栎（*Quercus petraea*）为优势种，另一个以欧洲鹅耳枥（*Carpinus betulus*）为优势种。两处鹅耳枥采样点均位于鹅耳枥矮林分中，陆生栎树采样点为成熟的同龄栎林。因该栎林内无溪流穿过，我们选取了邻近一处沿栎树占优林缘分布的溪流作为水生采样点位。枯落叶于脱落期采集，经室温风干后储存；后续我们还在不同的物理与微生物分解时长后再次采集枯落叶，以获得韧性值存在梯度差异的样本。在取食实验中，仅会为采集自同一采样点的碎屑食性动物提供对应生境的枯落叶…… # 大型碎屑食性动物与枯落叶间营养相互作用的力学驱动因子 [https://doi.org/10.5061/dryad.ngf1vhj2j](https://doi.org/10.5061/dryad.ngf1vhj2j) 本数据集为消耗测试的结果，旨在量化不同碎屑食性类群对枯落叶的消耗速率。 将枯落叶（欧洲鹅耳枥或夏栎）放置于森林溪流或森林土壤中进行分解，并于0至349天后采集样本。本次研究涉及的碎屑食性动物包含3个水生类群与5个陆生类群。消耗速率在实验室的微宇宙系统中进行测定。我们设置了无碎屑食性动物的枯落叶圆盘对照组，以校正消耗速率的测定误差。 我们测定了每一批枯落叶的平均韧性、柔软度、碳氮比以及氮百分含量。 我们测定了每个碎屑食性类群的平均颚部强度指数，并基于个体鲜体重测定或估算了每头个体的干体重。 ## 各数据列说明 * 生态系统：A=aqua...