Effects of spatio-temporal resource availability on pollinators and pest-natural enemies in fragmented agricultural landscapes (FRAGMENT III)

我们的目标是理清农业景观中特定的花卉资源对红石蜂和欧洲果园蜜蜂Osmia cornuta丰度和适合度的影响。这两种野生蜜蜂主宰着空巢独居蜜蜂的群落，并为油菜、苹果和草莓等多种农作物的授粉做出了贡献。我们的具体目标是：1)测试两种野生稻的丰度和相对优势度如何受喜好花型的数量和接近程度的影响。2)测试两种野生稻的幼虫食性和适合度如何受首选花型的数量和接近程度的影响。3)测试花卉资源的可获得性是否决定了它们对两种野生稻的影响，早花植物比晚花植物有更强的影响。4)测试木本栖息地的数量和邻近程度如何影响二角野生稻和角果野生稻的寄生，这可能会改变目标(1)、(2)和(3)项下研究的花卉资源可用性的积极影响。5)根据巢中发现的花粉和到景观中各自资源的最小距离来估计二角野生稻和角果野生稻的飞行距离。6)确定花卉资源有效性对二角野生稻和角叶野生稻影响最大的空间尺度。

We aim to disentangle the effects of specific floral resources in agricultural landscapes on the abundance and fitness of the red mason bees Osmia bicornis and the European orchard bee Osmia cornuta. These two species of wild bees dominate communities of cavity-nesting solitary bees and contribute to the pollination of a wide range of agricultural crops such as oilseed rape, apple and strawberry. Our specific objectives are:1) To test how the abundance and relative dominance of O. bicornis and O. cornuta is affected by the amount and proximity of preferred flower types.2) To test how the larval diet and fitness of O. bicornis and O. cornuta is affected by the amount and proximity of preferred flower types.3) To test if the timing of floral resource availability determines their effects on O. bicornis and O. cornuta, with early flowering plants having stronger effects than late flowering plants. 4) To test how amount and proximity of woody habitats affect parasitism of O. bicornis and O. cornuta, which may alter the positive effects of floral resource availability studied under objectives (1), (2) and (3).5) To estimate the flight distances of O. bicornis and O. cornuta according to the pollen found in the nests and the minimal distance to the respective resources in the landscape. 6) To determine the spatial scale at which floral resource availability effects on O. bicornis and O. cornuta are strongest.