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. 2010 Jul 30;46(3):378–390. doi: 10.1007/s00267-010-9536-9

Table 1.

Difference between photo-interpreted and NLCD 2001 derived tree canopy cover values by generalized NLCD land cover classes within each mapping zone

Zone Developed land cover Forest land cover Agriculture–grassland land cover Other land cover
n PI SE NLCD Diff n PI SE NLCD Diff n PI SE NLCD Diff n PI SE NLCD Diff
1 63 47.6 6.3 31.7 15.9* 799 80.0 1.4 69.4 10.6** 84 17.9 4.2 0.4 17.4** 46 13.0 5.0 0.4 12.6*
2 93 48.4 5.2 29.0 19.4** 695 87.5 1.3 70.7 16.8** 179 15.1 2.7 0.3 14.8** 29 17.2 7.0 0.5 16.7*
3 41 39.0 7.6 26.0 13.0 838 82.7 1.3 50.8 31.9** 118 11.0 2.9 1.2 9.9** 20 0.0 4.6a 1.9 −1.9
4 166 21.7 3.2 4.1 17.5** 508 61.0 2.2 21.5 39.6** 280 11.1 1.9 0.7 10.4** 46 8.7 4.2 0.3 8.4*
5 93 10.8 3.2 3.1 7.7* 53 41.5 6.8 16.0 25.6** 815 9.0 1.0 5.3 3.7** 39 15.4 5.8 1.8 13.6*
6 25 36.0 9.6 21.1 14.9 811 68.8 1.6 42.6 26.2** 122 15.6 3.3 3.5 12.0** 37 8.1 4.5 0.8 7.3
7 20 35.0 10.7 15.4 19.6 810 71.4 1.6 49.5 21.9** 133 19.5 3.4 0.9 18.6** 36 19.4 6.6 1.8 17.7**
8 43 14.0 5.3 1.1 12.9* 468 4.9 1.0 2.1 2.8** 464 1.3 0.5 0.5 0.8 23 17.4 7.9 11.1 6.3
9 21 19.0 8.6 5.8 13.2 787 20.8 1.4 14.3 6.5** 101 5.0 2.2 0.3 4.7* 21 4.8 4.6 0.2 4.5
10 20 40.0 11.0 6.7 33.3** 859 78.6 1.4 53.3 25.2** 124 21.0 3.7 6.9 14.1** 20 15.0 8.0 5.0 10.0
12 20 10.0 6.7 0.5 9.5 896 12.1 1.1 6.6 5.5** 58 5.2 2.9 0.3 4.9 39 0.0 2.5a 0.0 0.0
13 20 10.0 6.7 1.9 8.1 879 8.6 0.9 0.8 7.9** 22 13.6 7.3 1.6 12.0 81 3.7 2.1 0.1 3.6
14 43 16.3 5.6 1.1 15.2** 856 17.3 1.3 1.0 16.3** 72 5.6 2.7 0.7 4.8 29 3.4 3.4 0.5 2.9
15 26 34.6 9.3 12.9 21.7* 945 34.9 1.6 24.6 10.3** 35 8.6 4.7 0.6 7.9 25 20.0 8.0 0.9 19.1*
16 21 0.0 4.6a 8.6 −8.6 918 37.5 1.6 29.5 8.0** 41 0.0 2.4a 2.8 −2.8 23 0.0 4.3a 0.4 −0.4
17 27 14.8 6.8 10.1 4.7 757 19.8 1.4 8.6 11.2** 103 7.8 2.6 0.3 7.4** 113 0.0 0.9a 0.0 0.0
18 20 20.0 8.9 1.6 18.4 599 10.5 1.3 3.3 7.3** 359 4.5 1.1 0.3 4.1** 29 20.7 7.5 0.5 20.2**
19 20 5.0 4.9 2.6 2.4 664 62.3 1.9 47.1 15.3** 305 6.9 1.4 1.9 5.0** 20 15.0 8.0 1.7 13.3
20 20 10.0 6.7 1.1 8.9 158 51.3 4.0 23.2 28.1** 818 14.9 1.2 0.2 14.7** 20 25.0 9.7 2.1 22.9*
21 20 5.0 4.9 5.3 −0.3 785 50.2 1.8 42.8 7.4** 187 7.0 1.9 2.0 5.0** 20 0.0 4.9a 4.1 −4.1
22 20 15.0 8.0 2.2 12.8 800 7.8 0.9 1.9 5.9** 165 9.1 2.2 1.1 8.0** 26 11.5 6.3 5.4 6.1
23 20 5.0 4.9 3.3 1.7 812 21.2 1.4 13.7 7.5** 116 0.9 0.9 0.8 0.0 65 3.1 2.1 0.1 3.0
24 21 9.5 6.4 6.1 3.4 779 16.3 1.3 14.1 2.2 188 4.8 1.6 2.3 2.5 27 3.7 3.6 1.1 2.6
25 21 23.8 9.3 2.4 21.4* 817 16.9 1.3 7.3 9.6** 132 3.0 1.5 0.8 2.2 29 0.0 3.4a 0.1 −0.1
26 20 10.0 6.7 0.5 9.5 878 9.6 1.0 0.8 8.7** 99 9.1 2.9 0.1 9.0** 21 14.3 7.6 0.1 14.2
27 20 5.0 4.9 2.6 2.4 266 21.4 2.5 12.2 9.2** 711 3.7 0.7 0.0 3.6** 20 5.0 4.9 1.6 3.4
28 20 0.0 4.9a 11.3 −11.3* 749 61.5 1.8 48.4 13.1** 199 10.1 2.1 2.9 7.1** 36 5.6 3.8 3.5 2.0
29 20 5.0 4.9 2.8 2.2 448 21.9 2.0 14.1 7.8** 528 0.8 0.4 0.1 0.7 20 0.0 4.9a 1.1 −1.1
30 21 0.0 4.6a 0.4 −0.4 52 17.3 5.2 18.5 −1.2 916 1.0 0.3 0.1 0.8* 21 0.0 4.6a 0.8 −0.8
31 24 0.0 4.1a 0.9 −0.9 34 55.9 8.5 43.8 12.1 919 2.5 0.5 0.5 2.0** 31 9.7 5.3 1.1 8.5
32 102 14.7 3.5 3.5 11.2** 213 72.8 3.1 59.8 13.0** 676 10.8 1.2 0.8 10.0** 20 10.0 6.7 5.5 4.5
33 36 0.0 2.9a 1.3 −1.3 26 26.9 8.7 12.9 14.0 940 1.2 0.4 0.0 1.1** 22 4.5 4.4 1.7 2.9
34 34 0.0 2.7a 0.4 −0.4 300 24.0 2.5 4.0 20.0** 659 2.1 0.6 0.0 2.1** 20 5.0 4.9 0.5 4.5
35 39 12.8 5.4 8.5 4.4 654 24.2 1.7 19.0 5.2** 295 6.1 1.4 1.3 4.8** 20 5.0 4.9 1.3 3.7
36 75 14.7 4.1 8.2 6.5 419 52.0 2.4 22.1 29.9** 464 8.0 1.3 0.8 7.2** 42 4.8 3.3 4.3 0.4
37 64 32.8 5.9 19.8 13.0* 667 82.2 1.5 67.7 14.4** 202 13.4 2.4 0.6 12.7** 65 9.2 3.6 0.7 8.5*
38 49 8.2 3.9 3.6 4.6 26 76.9 8.3 59.7 17.2* 922 3.0 0.6 0.9 2.1** 21 14.3 7.6 4.8 9.5
39 59 6.8 3.3 0.8 6.0 24 70.8 9.3 45.1 25.8* 890 1.2 0.4 0.1 1.2** 35 2.9 2.8 0.1 2.7
40 46 4.3 3.0 1.0 3.3 32 62.5 8.6 66.8 −4.3 863 2.4 0.5 0.3 2.1** 56 1.8 1.8 2.1 −0.3
41 59 18.6 5.1 9.4 9.2 587 79.2 1.7 78.9 0.3 264 14.4 2.2 3.9 10.5** 86 25.6 4.7 24.7 0.9
42 86 9.3 3.1 4.6 4.7 74 83.8 4.3 80.1 3.7 831 3.1 0.6 1.6 1.6** 26 19.2 7.7 13.2 6.1
43 64 14.1 4.3 3.7 10.3* 143 81.8 3.2 70.7 11.1** 787 9.4 1.0 1.5 7.9** 20 25.0 9.7 13.4 11.6
44 56 30.4 6.1 22.7 7.6 622 89.1 1.3 77.5 11.5** 322 10.9 1.7 3.5 7.4** 20 30.0 10.2 13.4 16.6
45 54 20.4 5.5 9.6 10.8* 232 86.6 2.2 74.7 12.0** 710 3.9 0.7 1.2 2.7** 20 30.0 10.2 27.7 2.3
46 75 49.3 5.8 28.5 20.8** 715 85.7 1.3 73.9 11.8** 201 22.9 3.0 1.9 21.0** 22 27.3 9.5 24.5 2.8
47 67 16.4 4.5 2.1 14.3** 487 84.0 1.7 65.0 19.0** 441 10.2 1.4 0.5 9.7** 22 40.9 10.5 23.9 17.0
48 94 35.1 4.9 8.2 26.9** 595 86.4 1.4 76.7 9.7** 306 19.6 2.3 0.1 19.5** 20 10.0 6.7 0.5 9.5
49 127 15.0 3.2 5.5 9.5** 151 72.2 3.6 67.7 4.5 718 2.8 0.6 0.2 2.6** 21 19.0 8.6 4.9 14.1
50 69 39.1 5.9 12.6 26.5** 467 83.1 1.7 72.6 10.5** 431 10.7 1.5 0.9 9.8** 32 18.8 6.9 5.5 13.3
51 107 38.3 4.7 14.5 23.8** 534 88.2 1.4 70.2 18.0** 325 16.3 2.0 4.7 11.6** 34 50.0 8.6 19.9 30.1**
52 130 10.0 2.6 6.1 3.9 91 89.0 3.3 76.8 12.2** 774 7.1 0.9 1.3 5.8** 21 14.3 7.6 26.6 −12.3
53 71 54.9 5.9 32.9 22.0** 747 94.1 0.9 85.2 8.9** 172 30.8 3.5 9.0 21.8** 29 20.7 7.5 2.2 18.5*
54 130 40.0 4.3 30.6 9.4* 609 89.7 1.2 81.0 8.7** 253 35.2 3.0 1.9 33.3** 20 30.0 10.2 0.3 29.7**
55 66 47.0 6.1 28.1 18.9** 627 89.3 1.2 78.7 10.6** 267 25.1 2.7 2.0 23.1** 40 15.0 5.6 2.8 12.2*
56 199 26.1 3.1 8.0 18.2** 364 69.2 2.4 55.1 14.1** 249 17.3 2.4 2.4 14.9** 185 31.4 3.4 3.8 27.5**
57 59 35.6 6.2 29.3 6.3 748 93.7 0.9 86.8 6.9** 193 14.5 2.5 1.3 13.2** 20 35.0 10.7 0.2 34.8**
58 77 37.7 5.5 16.2 21.5** 549 84.7 1.5 66.8 17.9** 344 23.8 2.3 2.4 21.4** 30 13.3 6.2 3.1 10.2
59 109 45.9 4.8 17.5 28.4** 611 89.5 1.2 82.3 7.2** 280 27.5 2.7 1.6 25.9** 20 55.0 11.1 1.1 53.9**
60 138 29.7 3.9 10.8 19.0** 439 85.9 1.7 80.0 5.8** 369 22.5 2.2 0.4 22.1** 52 26.9 6.2 1.2 25.7**
61 91 45.1 5.2 24.0 21.0** 690 92.9 1.0 74.7 18.1** 207 17.4 2.6 4.2 13.2** 26 7.7 5.2 6.0 1.7
62 143 44.1 4.2 17.0 27.1** 589 87.4 1.4 82.1 5.4** 263 19.0 2.4 3.4 15.6** 20 20.0 8.9 6.6 13.4
63 72 34.7 5.6 17.8 16.9** 606 87.3 1.4 78.3 9.0** 312 18.3 2.2 9.5 8.8** 23 17.4 7.9 29.8 −12.4
64 75 38.7 5.6 33.6 5.1 716 90.5 1.1 87.1 3.5** 168 21.4 3.2 0.7 20.8** 27 29.6 8.8 1.6 28.0**
65 182 42.9 3.7 29.3 13.5** 686 88.9 1.2 85.9 3.0* 114 22.8 3.9 0.4 22.4** 21 9.5 6.4 0.6 8.9
66 38 42.1 8.0 7.4 34.7** 885 91.5 0.9 78.0 13.5** 59 28.8 5.9 4.2 24.6** 27 33.3 9.1 14.1 19.2*

n Number of photo interpreted points, PI photo-interpreted value, SE standard error of photo-interpretation estimate, NLCD NLCD derived cover value, Diff PI value minus NLCD value

* Significant difference at 95% confidence level; ** Significant difference at 99% confidence level

aNumber of points hitting the cover type was 0, so SE = 0. Number of points hitting cover type was set to one to calculate displayed SE and that adjusted value was used in the significance test to avoid testing using a zero standard error and confidence interval