OVERVIEW OF BELOWGROUND ECOLOGICAL RESEARCH AND FERTILIZATION EXPERIMENTS ON THE HOG ISLAND CHRONOSEQUENCE.


Frank P. Day.


Several intensive studies of primary production, belowground processes, and the controlling influences of groundwater hydrology and nitrogen availability along the Hog Island chronosequence were completed during the past year and summaries of the results are included in the following reports by Day, Lakshmi_and_Day, Conn_and_Day, Stevenson_and_Day, Weber_and_Day, and Dilustro_and_Day. Particularly noteworthy is the successful utilization of minirhizotrons in a fertilization experiment on the 36-year old dune. The fine scale observation of root dynamics on the same root cohorts through time allows a refined look at belowground effects, and this technique will be continued and expanded in use on the VCR-LTER site in the future.

Several long-term monitoring efforts and experiments are continuing along the Hog Island chronosequence. Groundwater monitoring is in its 4th year and a synthesis of those results will be generated this summer. Video recordings in the minirhizotrons are currently being obtained early and late in the growing season for the 2nd year following the initial year of frequent, more intensive observations. Digitization and interpretation of the current recordings await the establishment of the RA position proposed for the site. The long-term nitrogen fertilization experiment is in its 3rd year, and initial results will be analyzed and compiled this summer. Plant cover and species composition are being monitored in nitrogen ammended and control plots across the chronosequence.