Narr_Data_JAE_11_26_18.xlsx

We examined the relationship between nutrient availability and an abundant parasite capable of both horizontal and vertical transmission (<i>Hamiltosporidium tvaerminnensis</i>) of a planktonic crustacean, <i>Daphnia magna</i>, in rock pools on Baltic Sea Skerry islands. We found that the relative availability of nutrients directly affected infection prevalence; parasite prevalence was higher in pools with higher particulate N:P ratios. Infection prevalence was not related to <i>Daphnia</i> population densities. A complementary experiment that examined host responses to an N:P gradient in mesocosms indicated that high N:P ratios can increase spore load in the hosts.

本研究以波罗的海岩礁群岛的岩石池为研究生境，探究了营养可获得性与一种可同时进行水平和垂直传播的广布寄生虫——汉氏孢子虫（Hamiltosporidium tvaerminnensis）——及其宿主浮游甲壳动物大型溞（Daphnia magna）之间的关联。研究结果表明，营养物质的相对可获得性直接影响寄生虫感染率：颗粒态氮磷比更高的岩石池中，寄生虫感染率显著更高。寄生虫感染率与大型溞的种群密度无显著相关性。一项补充实验在中型实验生态系统（mesocosms）中探究了宿主对氮磷比梯度的响应，结果显示较高的氮磷比可提升宿主体内的孢子载量。