Detailed protocol for the Elevational Gradient sub-survey for the Comparative study of BugNet

In order to disentangle the differences between latitudinal and elevational effects on plant-insect and plant-invertebrate interactions we have designed an elevational gradient sub-survey for the comparative study in BugNet. As we have numerous comparative study collaborators across the globe we will have a range of data from differing latitudes which we can analyse to determine latitudinal effects on plant-pathogen and plant-invertebrate interactions. We are proposing a side study (with additional planned questions and publications to the core comparative study) which looks at sampling on an elevational gradient.

We ask collaborators who wish to participate in this sub-survey to sample a minimum of 5 comparative sites – one at the minimum elevation possible at their region (preferably at sea level), one at the maximum elevation possible with plant communities growing at their region, and at least three additional sites at equidistant elevations in between these two points. Please see figure 1 for a depiction of this method. To achieve this, simply divide the elevational gradient between the maximum and minimum into four and sample at the top of each four sections from the minimum point. More sites (6+) along the elevational gradient are very welcome too!

Figure 1. An example elevational gradient of a mountain/hill of 1800m – the first site is as close to sea level as possible (10m above sea level) and each consecutive site is 447m above this – calculated as 1800-10 = 1700m (range), 1700/4 = 447m so each site is at 447m above the next.

If you cannot sample at the exact elevation calculated, sample as close as possible and always record the elevation of each site.

At each of these 5 sites – the comparative site protocols will be followed (See bug-net.org/comparative-study for details). Please note that these 5 sites will contribute as your co-authorship data for both the core comparative manuscripts AND for the additional manuscript/manuscripts for the elevational gradient study. Therefore, we believe 5 sites (3 sites on top of the co-authorship requirement for the c