Post 4: Sampling Strategies

For this exercise, the area chosen for sampling was the Snyder-Middleswarth Natural Area .

The first sampling technique was: Area based, systematic 

24 Quadrats sampled, for a total sample time of 12hours 5minutes
(0, 110), (10, 120), (20, 110), (30, 120), (40, 110), (50, 120), (60, 110), (70, 120), (80, 110), (90, 120), (100, 110), (110, 120), (120, 110), (130, 120), (140, 110), (150, 120), (160, 110), (170, 120), (180, 110), (190, 120), (200, 110), (210, 120), (220, 110), (230, 120)

Plants sampled: 201
Species sampled: 6 

The second sampling technique was: Area based, random

24 Quadrats sampled, for a total sample time of 12hours 40minutes
(210, 50), (60, 50), (150, 200), (180, 100), (190, 110), (50, 90), (170, 190), (170, 60), (100, 150), (60, 130), (80, 40), (90, 120), (200, 250), (30, 160), (10, 60), (240, 180), (110, 120), (60, 40), (240, 0), (140, 70), (190, 180), (240, 180), (70, 80), (120, 250)

Plants sampled: 201
Species sampled: 6

The third sampling technique was: Area based, haphazard

24 Quadrats sampled, for a total sample time of 12 hours 38minutes
(5, 173), (73, 181), (127, 188), (177, 185), (233, 175), (223, 177), (13, 157), (83, 147), (132, 152), (175, 119), (212, 217), (15, 101), (75, 229), (119, 119), (174, 263), (213, 107), (17, 47), (77, 257), (125, 45), (175, 255), (230, 127), (17, 158), (69, 147), (129, 77)

Plants sampled: 234
Species sampled: 7

% error of density for the different sampling strategies 

Eastern Hemlock
Systematic: 4.2%
Random: 6.9%
Haphazard: 13.5%

Sweet Birch
Systematic: 14.9%
Random: 29.1%
Haphazard: 18.5%

Yellow Birch
Systematic: 4.3%
Random: 12%
Haphazard: 0.5%

Chestnut Oak
Systematic: 23.8%
Random: 14.3%
Haphazard: X

Red Maple
Systematic: 15.9%
Random: 12.4%
Haphazard: 0%

Striped Maple
Systematic: X
Random: X
Haphazard: 76%

White Pine
Systematic: 98.8%
Random: 98.8%
Haphazard: 48.8%

In terms of time, the most efficient sampling technique was the systematic technique, at 12 hours 5 minutes. This sampling technique was the most accurate sampling technique for the most common species (Eastern Hemlock, occurring at a relative frequency of 33.8), with a percentage error of 4.2%. However, the most accurate sampling technique for the rarest species (White Pine, occurring at a relative frequency of1.9) was haphazard, with a percentage error of 48.8%. 

The accuracy of each sampling strategy definitely declined when used with rare species, in comparison to common species. However, the decline in accuracy for each sampling technique may have been reduced if more than 24 sample points were taken. With only 24 sample points, not all species were captured in some of the sample techniques, resulting in an inaccurate estimation of the number/abundance of species in the community.

My numbers may also be inaccurate. The site kept getting blocked on my laptop and I had to restart many times.