Land-use effects on plant-herbivore stoichiometry: micro- and macronutrients

土地利用对植物-草食动物化学计量的影响：微量和常量营养素

• 批准号: 252359497
• 负责人: Professor Dr. Nico Blüthgen
• 金额: --
• 依托单位: Arbeitsgruppe Ecological Networks
• 依托单位国家: 德国
• 项目类别: Infrastructure Priority Programmes
• 财政年份: 2014
• 资助国家: 德国
• 起止时间: 2013-12-31 至 2019-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/252359497?language=en
• 关键词: Land; use; effects; plant; herbivore

Previous work has shown that land-use intensity strongly alters element concentrations (stoichiometry) of grassland plants (project 'Biocomp'). Here we continue the monitoring of the community biomass quality and will extend this stoichiometric analysis to herbivores, focusing not only on macronutrients but on micronutrients and trace elements as well. Intraspecific variation in stoichiometry across plant and herbivore populations along the land use gradient will give us insights into the extent of plasticity or homeostasis of specialised and generalised species, which may constrain their distribution and performance. Elemental composition of community biomass and single plant species will be related to plant diversity, land use, particularly fertilization and soil resources. We expect a strongly element-dependent response with a higher level of stoichiometric mismatch for single species compared to community biomass and higher variability among species particularly in low productive species-rich grasslands. Similarly, composition of herbivores will be related to variation in their host plants. We hypothesize that apart from secondary metabolites, constraints related to nutritional characteristics of host plants contribute to changes in herbivore performance, host plant choices and herbivore assemblage composition. Based on feeding trials, we compare the consumption by target herbivores (e.g. grasshoppers, caterpillars) and their performance on leaf material sampled along the land use gradient. We expect that those species that predominantly occur in unfertilized grasslands perform less well on plants grown in fertilized sites and vice versa, due to respective nutrient and trace element imbalances in their diet. Additionally, we will analyse the inter-annual variability in plant biomass macronutrient composition across the gradients of land-use intensity, plant species richness and productivity and will thereby address important stoichiometric aspects that will contribute to a better understanding of the biodiversity - ecosystem stability relationship.

以前的工作表明，土地利用强度强烈改变元素浓度（化学计量）的草原植物（项目“生物”）。在这里，我们继续监测社区生物量的质量，并将这种化学计量分析，以草食动物，不仅侧重于常量营养素，但微量营养素和微量元素以及。植物和食草动物种群沿着土地利用梯度的化学计量的种内变化将使我们深入了解专门化和一般化物种的可塑性或稳态的程度，这可能会限制它们的分布和性能。群落生物量和植物种的元素组成与植物多样性、土地利用，特别是施肥和土壤资源有关。我们预计，一个强烈的元素依赖性的反应与更高水平的化学计量不匹配的单一物种相比，社区生物量和物种之间的变异性更高，特别是在低生产力的物种丰富的草原。同样，食草动物的组成也与其宿主植物的变异有关。我们推测，除了次生代谢产物，与寄主植物的营养特性的限制有助于草食动物的性能，寄主植物的选择和草食动物组合组成的变化。基于饲养试验，我们比较了目标食草动物（例如蚱蜢、毛毛虫）的消耗量及其对沿着土地利用梯度采样的树叶材料的表现。我们预计，这些物种主要出现在未施肥的草原上，表现不太好的植物生长在施肥的网站，反之亦然，由于各自的营养和微量元素的饮食不平衡。此外，我们将分析跨梯度的土地利用强度，植物物种丰富度和生产力的植物生物量常量营养素组成的年际变化，从而解决重要的化学计量方面，这将有助于更好地了解生物多样性-生态系统稳定性的关系。