Richmond I C, Perron M C, Boyle S P, Pick F R
Department of Biology, University of Ottawa, 30 Marie Curie Private, Ottawa, ON K1N 6N5 Canada.
Department of Biology, Concordia University, 7141 Sherbrooke St. W., Montreal, QC H4B 1R6 Canada.
Landsc Ecol. 2024;39(3):63. doi: 10.1007/s10980-024-01817-z. Epub 2024 Feb 28.
The successful dispersal of an animal depends, partly, on landscape connectivity. Urbanization poses risks to dispersal activities by increasing hostile land cover types.
We investigated how connectivity of urban ponds impacted Odonata communities (dragonflies and damselflies), an order of semi-aquatic insects that actively disperse.
We sampled 41 constructed stormwater ponds and 8 natural ponds in a metropolitan area. The effect of connectivity and the quantity of available adjacent habitats was tested at different scales for dragonflies (900 m) and damselflies (300 m), determined by a literature analysis, to account for differences in suborder dispersal capabilities.
Lower levels of connectivity and fewer nearest neighbours negatively impacted abundance, species richness, and composition of dragonflies (p values < 0.01, R = 0.18-0.70). Adult dragonfly abundance had a stronger positive relationship with connectivity than species richness. In particular, the abundance of adult dragonfly found almost exclusively at natural ponds, had a positive relationship with connectivity. Connectivity and the number of nearest neighbours had no significant impact on damselflies apart from a slight negative relationship between connectivity and species richness (p value = 0.02, R = 0.11). Natural ponds had significantly higher levels of connectivity when compared to stormwater ponds.
Our results suggest that dragonflies are positively affected by increased connectivity in an urban landscape, with no benefit of connectivity to damselflies at the scale measured. We recommend intentional planning of urban stormwater pond networks, where individual ponds can act as stepping stones, incorporated with strategic inclusion of beneficial land cover types.
The online version contains supplementary material available at 10.1007/s10980-024-01817-z.
动物的成功扩散部分取决于景观连通性。城市化通过增加不利的土地覆盖类型给扩散活动带来风险。
我们研究了城市池塘的连通性如何影响蜻蜓目群落（蜻蜓和豆娘），蜻蜓目是一类积极扩散的半水生昆虫。
我们在一个大都市地区对41个建造的雨水池塘和8个天然池塘进行了采样。根据文献分析确定，针对蜻蜓（900米）和豆娘（300米）在不同尺度上测试了连通性和可用相邻栖息地数量的影响，以考虑亚目扩散能力的差异。
较低的连通性水平和较少的最近邻对蜻蜓的丰度、物种丰富度和组成产生负面影响（p值<0.01，R = 0.18 - 0.70）。成年蜻蜓的丰度与连通性的正相关关系比物种丰富度更强。特别是，几乎仅在天然池塘中发现的成年蜻蜓的丰度与连通性呈正相关。连通性和最近邻的数量对豆娘没有显著影响，除了连通性与物种丰富度之间有轻微的负相关关系（p值 = 0.02，R = 0.11）。与雨水池塘相比，天然池塘的连通性水平显著更高。
我们的结果表明，在城市景观中，蜻蜓受到连通性增加的积极影响，而在测量的尺度上，连通性对豆娘没有益处。我们建议对城市雨水池塘网络进行有意规划，其中单个池塘可作为踏脚石，并战略性地纳入有益的土地覆盖类型。
在线版本包含可在10.1007/s10980 - 024 - 01817 - z获取的补充材料。
