传粉昆虫下降背景下的授粉生态弹性: 内涵、机制和展望

谢正华, 王有琼, 曹军, 王健敏, 安建东

Ecological resilience of pollination in the face of pollinator decline: Content, mechanism and perspective

Zhenghua Xie, Youqiong Wang, Jun Cao, Jianmin Wang, Jiandong An

图6 跨尺度弹性引起授粉生态弹性的机制示意图。在生态系统中, 假设空间分布的开花植物a、b、c、d、e和f存在大、中、小3种传粉功能团, 传粉功能团空间传粉尺度(或空间搜索范围)分别约为300 m、1,000 m和1,500 m, 个体大的传粉昆虫空间跨尺度为开花植物传粉(A)。3种传粉功能团在个体大小(body size)轴上形成不连续性的分布(B)。开花植物a接收3个传粉功能团传粉, b、d和f接收2个传粉功能团传粉, c和e仅接收1个传粉功能团传粉, 因此开花植物a的传粉功能团跨尺度传粉功能冗余程度高于其他开花植物(C)。以开花植物a为对象, 当某搜索范围(如300 m)的传粉功能团访花密度下降时, 其他尺度(如1,500 m)的传粉功能团增加访花密度, 传播等量花粉, 形成授粉生态弹性(D)。在(C)和(D)中, 线条长度示意对应的传粉昆虫空间传粉范围, 线条宽度示意传粉昆虫空间传粉功能。

Fig. 6 Conceptual diagram showing the mechanical effect of cross-scale resilience on ecological resilience of pollination. The ecosystems are hypothesized to have three functional groups with large (1,500 m), medium (1,000 m) and small (300 m) spatial scales (i.e., foraging ranges), respectively, and they pollinate flowering plants a, b, c, d, e and f spatially distributed in ecosystems. The large-sized functional groups pollinate plants across scale (A). The three functional groups of pollinators are distributed discontinuously along the x-axis of body size (B). Flowering plant a is pollinated by three functional groups, flowering plant b, d and f are pollinated by two functional groups, and flowering plant c and e are pollinated by just one functional groups. Therefore, the level of cross-scale redundancy of pollinator assemblages for plant a is higher than that of other plants (C). If the visit density of a certain functional group of pollinators with a specific foraging range (e.g. 300 m) declines (e.g. plant a), other functional groups of pollinators with a large spatial foraging range (e.g. 1,500 m) increase their visit densities. The amount of pollens delivered by the pollinator assemblages on the stigma surface of plant a is similar. The pollinator communities have the ecological resilience of pollination (D). In (C) and (D), the lengths of lines corresponding to the pollinators indicate the foraging ranges of pollinators and the widths of lines quantify their pollination functioning.