06 Data Gathering

Plant abundance measurements and calculations.

Differentiation of the ground cover in open fields into three conditions:

  • Bare and /or exposed ground (Pabeg).  Moss covered open ground was considered in this group due to its rarity. Would it have been more abundant it would have been considered on its own group.
  • Ground tightly covered by plants with only unexposed bare ground under their foliage (Patgc).  Bundle and caespitose grasses, racemose plants such as Bird’s Foot Trefoil, rhizomatous plant clusters such as Solidago complexes and low, thick foliated shrubs like Gray Dogwood were considered in this group.
  • Plants allowing either exposed ground or growth of other plants under their foliage (Prgc).  Long stemmed forbs, individual grasses, tall shrubs, and trees typically fell into this group.

The abundance reported in the case of the first two conditions represents absolute abundance.  For any given area, the sum of the two equals 100% (Total absolute ground cover; Tagc). In the third case, the values reported represent relative abundances (Prgc), and its sum represents total relative ground cover (Trgc)

Total absolute and relative cover, (Sum of all reported abundances)

Total absolute ground cover; (Tagc)

Total relative ground cover, (Trgc)

Abs to rel cover factor is given by the relation:  1- Trgc/Tagc

Total absolute grass cover represents the contribution to Tagc by grasses only

Total absolute forb cover represents the contribution to Tagc by forbs only

Total absolute tree/shrub cover represents the contribution to Tagc by trees and shrubs

Basal area measurements were used to determine tree density and abundance in forested tesserae.

Vertebrate observations.

The identification of Reptiles and Mammals in the area was inferred from direct encounters, scats, tracks and other evidence of their activity except for the Meadow Jumping mouse (Zapus hudsonicus), one specimen of which was unfortunately killed in one of the glue traps at MC5.

Most birds observed were photographed or their songs recorded to confirm identification. Nesting locations detected at any given time of the year were identified and mapped.

Invertebrate observations.

Invertebrates were documented photographically during continuous random walks (ideally Markov-chain walks) through each tesserae. The photographs time stamp was used to determine the frequency of encounter of each species as discussed below. In some cases – specimens were collected for identification purposes.  Presence of arthropod remnants was also assessed in soil samples as indicated in the Indices section below.

Due to the approximate nature of the surveying process used, invertebrate abundances were reported in terms of powers of two and rounded to the nearest whole number.

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