EAPSI:Understanding How Seabird Guano Impacts Nutrient Availability and Plant Community Composition in Montane Terrestrial Ecosystems

为了更好地了解植物-动物和陆地-海洋的联系，该项目将研究海鸟对新西兰森林地区的氮(N)输入。这是一个需要了解的重要动态，因为一些岛屿正在经历捕食者的迁徙以及本地栖息地和海鸟的恢复，而另一些岛屿则继续经历海鸟数量的下降。这项工作将与奥克兰科技大学(AUT)的大卫·唐斯博士合作进行。唐斯博士有20多年研究新西兰生态系统的经验，也有多年研究海鸟岛屿及其恢复的经验。主要研究问题包括：海鸟种群密度如何影响营养补贴，植物利用多少海洋来源的氮，以及这些海鸟引起的土壤和植物变化是否影响植被群落结构。假设随着海鸟洞穴密度的增加，来自海鸟的N将增加，海鸟群落中的植物群落结构将发生变化，由适应于利用海鸟提供的脉冲补贴的本地植物组成的比例将变得更大。新西兰的这项研究将与之前在夏威夷进行的工作进行比较，以更好地了解海洋-海鸟-陆地生态系统作为海鸟的联系？全球范围内的人口都在减少。将测量土壤和树叶的N同位素组成，以了解从海洋带入陆地系统的N是如何在生态系统中移动的。高的d15N值可以作为海洋来源N的标志。一个两端成员，一个同位素混合模型将被用来评估土壤和树叶中来自海洋来源的N的百分比，即海鸟。还将测量植被群落结构，以确定海鸟和非海鸟地区在群落组成方面是否存在明显差异。该奖项是与新西兰皇家学会合作资助的。

To better understand plant-animal and terrestrial-marine linkages, the project will study the input of nitrogen (N) by seabirds into forested areas in New Zealand. This is an important dynamic to understand as some islands are undergoing predator removal and native habitat and seabird restoration, while others continue to experience seabird declines. This work will be conducted in collaboration with Dr. David Towns of the Auckland University of Technology (AUT). Dr. Towns has over 20 years of experience studying ecosystems in New Zealand as well as many years working with seabird islands and their restoration. Primary research questions include: how do seabird population densities impact nutrient subsidies, how much marine-sourced N do the plants utilize, and do these seabird induced changes in the soil and plants impact the vegetation community structure. It is hypothesized that as seabird burrow density increases, N from seabirds will increase, and vegetation community structure in seabird communities will change, becoming more significantly composed of native plants adapted to utilize the pulsed subsidies provided by the seabirds. This New Zealand research will be compared with previous work in Hawaii to better understand linkages of the marine-seabird-terrestrial ecosystem as seabirds? populations decline across the globe. The N isotope composition of soil and leaves will be measured to understand how N brought from the ocean to the terrestrial system moves through the ecosystem. High d15N values may serve as a signature of marine source of N. A two end member, one isotope mixing model will be used to assess the percentage of N in soil and leaves that is from a marine source, i.e. seabirds. Vegetation community structure will also be measured to determine if there is an appreciable difference between seabird and non-seabird areas in terms of community composition. This award is funded in collaboration with the Royal Society of New Zealand.