Saccaggi D L, Wilson J R U, Terblanche J S
Plant Health Diagnostic Services, Department of Agriculture, Land Reform and Rural Development, Private Bag X5015, Stellenbosch 7599, South Africa.
Centre for Invasion Biology, Department of Conservation Ecology and Entomology, Faculty of AgriSciences, Stellenbosch University, Private Bag X1, Stellenbosch 7602, South Africa.
Curr Res Insect Sci. 2021 Feb 18;1:100011. doi: 10.1016/j.cris.2021.100011. eCollection 2021.
The establishment success of a population is a function of abiotic and biotic factors and introduction dynamics. Understanding how these factors interact has direct consequences for understanding and managing biological invasions and for applied ecology more generally. Here we use a mesocosm approach to explore how the size of founding populations and the number of introduction events interact with environmental conditions (temperature) to determine the establishment success of laboratory-reared We found that temperature played the biggest role in establishment success, eclipsing the role of the other experimental factors when viewed overall. Under optimal temperature conditions propagule pressure was of negligible importance to establishment success. At adverse temperatures, however, establishment success increased with the total founding population size. This effect was considerably stronger at the cold than at the hot extreme. Whether the population was introduced all at once or by increments (changing the number of introduction events) had a negligible global effect. However, once again, a stronger effect of increasing number of introduction events was seen at adverse temperatures, with hot and cold extremes revealing opposite effects: adding flies incrementally decreased their establishment success at the hot extreme, but increased it at the cold extreme. These differing effects at hot and cold thermal extremes implies that different establishment mechanisms are at play at either extreme. These results suggest that the effort required to prevent (or conversely, to facilitate) the establishment of populations varies with the environment in ways that can be complicated but predictable.
种群的成功建立是由非生物和生物因素以及引入动态所决定的。了解这些因素如何相互作用对于理解和管理生物入侵以及更广泛地应用生态学具有直接影响。在这里，我们使用中宇宙方法来探究初始种群的大小和引入事件的数量如何与环境条件（温度）相互作用，以确定实验室饲养种群的建立成功率。我们发现，温度对建立成功率的影响最大，从总体来看，其作用超过了其他实验因素。在最佳温度条件下，繁殖体压力对建立成功率的影响可忽略不计。然而，在不利温度条件下，建立成功率随初始种群的总大小而增加。这种影响在寒冷极端条件下比在炎热极端条件下要强得多。种群是一次性引入还是分批引入（改变引入事件的数量）在总体上的影响可忽略不计。然而，同样地，在不利温度条件下，引入事件数量增加的影响更强，炎热和寒冷极端条件下呈现出相反的效果：在炎热极端条件下分批添加果蝇会降低其建立成功率，但在寒冷极端条件下则会提高。在炎热和寒冷极端温度下的这些不同影响意味着在两种极端情况下发挥作用的建立机制不同。这些结果表明，防止（或相反，促进）种群建立所需的努力会因环境而异，其方式可能复杂但具有可预测性。
