Yale University School of Forestry & Environmental Studies FES519B - Methods of Ecosystem Analysis 1998

Presented by Daniel Avery, Wendy Barber, Todd Forrest, H. Bradley Kahn, Fran Raymond, and Eli Sagor  Yale University School of Forestry and Environmental Studies  Methods of Ecosystem Analysis -- Spring, 1998 - FES 519b

This page describes our attempt to determine the amounts of several mineral elements in three sassafras (Sassafras albidum) trees from Southern Connecticut.

I. Objective:      To determine the concentrations and amounts of four mineral elements, Calcium, Magnesium, Potassium, and Phosphorus, in the wood, bark, and branches of four sassafras trees. The study site, a hemlock-mixed hardwood forest in the Crooked Brook watershed in North Branford, CT, USA, is described in more detail here

 

II. Methods:      A. Tissue Sample: Three trees were felled to provide the total sample, from which sub-samples were derived. The process is described in graphic detail at the FES 519b Allometry page.      B.Tissue Sub-Sampling:           1. Wood: "Cookies" (1 inch thick cross sections) were systematically isolated from subject trees, and smaller samples were isolated from each cookie.           2. Bark: Isolated from the cookies.           3. Branches: We chopped up and brought back one representative large, medium, and small branch.

 

III. Laboratory Analysis:      A. Sample Preparation:           1. After isolating our sample tissues, we took "green" weights, then determined the oven dry-weight and ashed each sample in the muffle furnace.           2. Working now with ashes, we dissolved each sample in Nitric Acid.      B. FINALLY, we got to play with the really expensive stuff: the Inductively-Coupled Plasmaspectrometer (ICP)!      C.The ICP generously gave us reams of data, which we effortlessly synthesized (er... crunched) into something meaningful  The entire process can be viewed as a Flow Chart