FORESTS FALL 2017

Species-Area Relationship Lab Assignment

This is the follow-up to the field-work we did for first lab, 7 September. Your assignment:

I have combined the data for the three groups in a single spread-sheet and shared it with you.  Keep in mind the sort of habitat/forest where data were collected: a small area of relatively mature forest near the sugar bush.  Because our lab was truncated by rain, I have added similar data for two other sites from a previous year.  Those sites are: a) a patch of younger forest (that was previously agricultural field) behind Jennings, and b) the grassy meadow between the Purple Carrot Farm and the Orchard houses.

Your assigned work is to:

1. Develop graphical visualizations of the species-area relationships. Graph the data set in a way that you think best demonstrates the manner in which total species richness is related to sample area and allows you to compare findings among replicates and between sites/habitats.  For example, you might want to combine some data-series into a single graph, or you might want to use several parallel graphs; you decide what works best.  It is relatively quick and easy to experiment with different graphical formats using graphing/charting functions in spreadsheets (use whatever you have available: Google Sheets is free; some of you may be comfortable with Excel; if you use 'Numbers' Apple software make sure you 'save as' an xls (excel) file when you submit).  You might also experiment with different axis scalings (remember visualizations of species-area relationships in class/notes). Choose some final graphs to include in your report; make sure that they follow all the standard guideliens for graphs -- label the axes, provide a caption... We will spend a few minutes in class looking at basic approaches in spreadsheets. (There are fancier scientific graphics tools available as freeware if you're interested; here's a free one, called VEUSZ, that's pretty easy to use).

2. Interpret and report results. Use selected graphs to illustrate a report in which you:
    a) Frame the project/approach in a few sentences and, especially, frame a question or two that you use these data to address (for example, you might be asking about differences between sites, or 'shape' of the species-area relationship, or...) and any initial predictions or expectations you had.
    b) Describe any patterns you see; specifically, focusing on what they say about the questions you have framed (e.g., are there interesting similarities or differences among replicates within each habitat? Among habitats?) Refer to specific graphs to illustrate your points as called for.
    c) Interpret these patterns; especially, consider how and whether they do or do not conform to your initial hypothesis/predictions.   What might be reasons for patterns observed?  
    d) From these speculations about reasons for patterns formulate and explicitly state at least one new hypothesis about the causes of  patterns observed.  How might you test your hypothesis (What does your hypothesis predict and how can you assess these predictions?)

YOUR REPORT should be a coherent/integrated document that BEGINS with a brief statement of questions addressed and the patterns you expected to see, a brief description of the data-set, and a main focus on interpreting the results.  THIS NEED NOT BE LONG.  Text part shouldn't be more than a couple of pages. MAKE SURE your graphs are clearly labeled, and that you follow good, basic graphing practice (label axes, provide legends or captions that explain, etc.).  

SUBMIT THE WRITE-UP AS A GOOGLE DOCUMENT SHARED WITH ME OR AS AN EDITABLE WORD-PROCESSOR FILE.  You can insert graphs directly in the document (best) or submit them as separate files (e.g. as .jpg images or part of the whole spreadsheet).  INCLUDE YOUR NAME IN THE FILENAMES in all submissions (e.g.,  'kwoods_speciesarea_report.docx').  DUE MON 25 SEPT  (I'll accept printed work, but prefer the digital form)