Update and Continuing TASpeR into 2020
Although our laboratory at Boston University was shut down for about 3 months this spring due to Covid-19, we have now returned to research activities. In the next several weeks we will have data on the fallen leaf samples, and will be working in the lab to obtain phosphorus concentrations of the leaves that were submitted in 2019. We are very excited for these next steps, and also want to share some preliminary findings from the green leaf samples submitted in 2019. We hope that you can join us again in 2020 and thank you in advance for supporting this scientific research!!!
For 2020, we are focusing again on red maple. In addition, for those who plan to sample in forested or non-managed areas we are also interested in the plants growing next to red maple in order to understand how red maple may change relative to the rest of the community of plants along its geographic range. We have provided an updated sampling protocol and datasheet for 2020. If you are interested in joining us again this year please let us know by completing this form so we know how many participants we will have this year: here is the link to the form
Green leaf samples – Preliminary results
Mean annual temperature
We found that the %N in the red maple leaves (mass of nitrogen in leaves / mass of leaf *100) was significantly related to the mean annual temperature of the collection locations (p<0.01). On average, for every degree Celsius increase in mean annual temperature, the %N in the leaves decreased by about 0.02%. Although the relationship between mean annual temperature and %N was significant, this relationship was not particularly strong. In fact, mean annual temperature explained only about 8% of the variation in leaf %N, suggesting other factors could help to account for the remainder of the variation. We are currently working on developing models to include additional information from the data sheets that participants filled out and submitted with their leaves.
Mean annual precipitation
We did not find any significant correlation between mean annual precipitation and %N in the red maple leaves collected in 2019 (Figure 2). However, in future analyses of this data we will leverage gridded weather data from 2019 (e.g., https://daymet.ornl.gov/) to understand how the actual observed weather conditions may affect %N in red maple leaves. We anticipate that the actual observed weather conditions will be important, particularly because several participants noted in their datasheets that 2019 was an abnormally droughty year.
We appreciate the participants’ contribution to this research and and we look forward to continuing this project into 2020.