Biodiversity and trophic interactions in agricultural mosaic landscapes, comparing bees, wasps and their natural enemies

全球生物多样性正在以惊人的速度下降，传统的保护区已不足以减缓这种下降，因此，管理土地对保护的潜在贡献日益得到承认。这包括扩大视野，从外地和农场景观水平，考虑到往往被忽视的空间和时间周转人为镶嵌景观。在这里，我们将使用一个高度重复的研究设计与标准化的筑巢资源的实验曝光，研究生境类型的景观多样性的相对重要性，使用陷阱筑巢蜜蜂，黄蜂和它们的天敌。我们将分析分区生物多样性的尺度依赖性，量化宿主-寄生蜂和捕食者-捕食者的相互作用，以及使用完全量化的相互作用网络进行食物网统计（根据Tylianakis等人2007，Nature 445：2002-5）。我们将展示如何在我们的马赛克景观（和不同年份）的主要栖息地类型有助于整体物种丰富度，比较小麦，油菜，草地，田间边缘地带，休耕和林缘，这代表了人为干扰的梯度。我们将研究景观组成如何影响的相对贡献的六个栖息地类型的物种丰富度，专注于一个梯度的简单到复杂的结构景观。此外，我们预计敌人的丰富程度与宿主/猎物的死亡率有关，因此我们将对这个备受争议的话题做出贡献。农业景观的镶嵌结构允许研究鲜为人知的景观配置的影响，包括跨生境的溢出效应，抑制扩散（通过敌对的谷物领域）和促进（通过草地走廊）。标记蜜蜂和黄蜂个体的实验可以描述觅食行为和资源利用的栖息地。

Global biodiversity is declining at an alarming rate and traditional conservation areas are no longer sufficient to slow this decline, so the potential contribution of managed land for conservation is increasingly acknowledged. This includes a broadening of the perspective from the field and farm to the landscape level, considering the often neglected spatial and temporal turnover in anthropogenic mosaic landscapes. Here we will use a highly replicated study design with the experimental exposure of standardized nesting resources to examine the relative importance of habitat type to landscape diversity using trap-nesting bees, wasps and their natural enemies. We will analyze the scale-dependence of partitioned biodiversity and quantify host-parasitoid and prey-predator interactions, as well as make food web statistics with a fully quantified interaction web (following Tylianakis et al. 2007, Nature 445: 2002-5). We will show how the major habitat types in our mosaic landscapes (and different years) contribute to overall species richness, comparing wheat, oilseed rape, grassland, field margin strips, fallows and forest margins, which represent a gradient of anthropogenic disturbance. We will examine how landscape composition influences the relative contribution of the six habitat types to species richness by focusing on a gradient of simple to complex structured landscapes. Further, we expect enemy richness to be related to host/prey mortality, so we will contribute to this highly debated topic. The mosaic structure of agricultural landscapes allow to study little known effects of landscape configuration, including spillover effects across habitats, inhibition of dispersal (by hostile cereal fields) and facilitation (by grassy corridors). Experiments with marked bee and wasp individuals allow to describe foraging behaviour and resource use across habitats.