Diversifying crop rotations with temporary grasslands - Université de ...

At the end of the experiment in spring 2009, the emerged weed communities were
characterized by a number of indicator species for different crop treatments (Table 10). Ten
weed species were significantly associated with one or several annual crop successions (T9-
T11) and appeared only occasionally in the perennial crops. Six species were significantly
associated with spring-sown alfalfa (T5) and one species (T. officinale) with both spring-sown
perennial crops. Only one species (S. media)
had an increased and nearly significant indicator
value in autumn sown alfalfa (T2) while all other autumn sown perennial crop treatments had
no significant indicator species. The ten indicator species of annual crops included the most
abundant weed species, while most of the indicators for perennial crops were less abundant
(see column ‘Total abundance’ in Table 10).
Table 10: Indicator Species Analysis of emerged weed communities in 9 crop treatments at the end of the
experiment in spring 2009.
Species
Total Total
freq. abund.
(1) (2)
Treatment (3)
Alfalfa Cocksfoot Wheat-Barley
Aut. Spring Aut. T+ T+ T-
C- C+ C+ C+ C+ C- M
T2 T4 T5 T6 T7 T8 T9 T11 T10
T.
IVmax
p-value
# # ---------------Indicator Values-------------
Indicators for autumn sown perennial crops
Stellaria media 15 36 13 0 2 0 0 0 1 1 1 T2 0.0728 ns
Indicators for spring-sown perennial crops
Poa annua
C. album +polysp.
Atriplex patula
Anagallis arvensis
Capsella bursa-pastoris
Sonchus asper +oleraceus
6
12
4
41
6
60
7
23
22
109
7
105
0 0 11 1
0 0 15 0
0 0 18 0
1 4 24 1
1 0 27 0
12 2 13 0
3
0
0
0
0
4
0
0
0
0
0
1
0
1
0
2
0
9
0
4
0
4
0
5
0
1
0
3
0
4
0.0326 *
|
0.0322 *
|
0.0022 **
T5
0.0004 ***
|
0.0002 ***
|
0.1082 ns
Taraxacum officinale 21 31 1 0 16 20 0 0 0 0 0 T6 0.0012 **
Indicators for annual crops
P. pers. +lapathifolium 11 68 0 0 0 0 0 0 29 0 0 | 0.0026 **
Fallopia convolvulus 56 218 8 16 1 0 0 0 31 4 5 | 0.0002 ***
Polygonum aviculare 41 151 0 15 0 0 0 0 23 2 15 T9 0.0038 **
Veronica persica 73 502 8 5 2 0 0 0 27 22 7 | 0.0016 **
Sinapis arvensis 42 1062 0 0 0 0 0 0 45 38 1 | 0.0002 ***
Papaver rhoeas 16 33 0 0 0 0 0 0 3 24 9 | 0.0008 ***
Galium aparine 59 3707 0 0 0 0 0 0 36 50 13 T11 0.0002 ***
Alopecurus myosuroides 62 1347 1 0 0 0 0 0 35 39 22 | 0.0002 ***
Lolium multiflorum
Bromus sterilis
35
23
132
119
1
1
0
0
2
0
0
0
0
0
0
0
3
0
3
0
54
81
0.0002 ***
T10
0.0002 ***
High Indicator Values (IV) are shaded in darker grey with three steps: IV≥10, IV≥20 and IV≥30.
(1) Total number of quadrats where the species is present (total = 152 quadrats, thus 16-18 quadrats/treatment).
(2) Total number of plants in all quadrats.
(3) See Table 1 for crop treatments T2-T11.
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