Impact of monoculture (rubber, pineapple, bamboo and tea) practices on earthworm (Oligochaeta) communities – A case study from West Tripura, India

In tropics, tree plantations are becoming common land use systems for different reasons including the shift in timber production, restoration of degraded lands etc. Rubber, pineapple, tea and bamboo are widely cultivated in Tripura.
Most of the rubber, pineapple, bamboo and tea plantations in Tripura derived either from waste or fallows over hill slopes, hillocks and plains. Earthworms, dominate soil macro-fauna in tropical ecosystems and play an important role in maintaining soil fertility, ecosystem function and production.

5. (1) Mixed Forest (2) Mixed Fruit Plantation

6. (3) Rubber Plantation (4) Pineapple Plantation
(5) Bamboo Plantation (6) Tea Plantation

7. 5%
10%
30%
55%
Rubber
Tea
Pineapple
Bamboo


Fig. 1 Percentage area of different monoculture plantations in
West Tripura

9. RESULTS
Earthworms of the monoculture and polyculture
plantations
A. Pontoscolex corethrurus B. Drawida assamensis
Dominant earthworm of
rubber and tea plantation
Dominant earthworm of
pineapple plantation

10. Metaphire houlleti Metaphire posthuma Perionyx excavatus
Kanchuria sp.1 Lampito mauritii Amynthus alexandri

11. Eutyphoeus gigas Eutyphoeus scutarius E. comillahnus
Eutyphoeus sp.1 Eutyphoeus gammiei Drawida p. papillifer

12. Drawida nepalensis Kanchuria sumerianus Etyphoeus assamensis
Dichogaster affinis Octochaetona beatrix Gordidrilus elegans

13. Earthworms and
family
CategoriesMF MFP RP PP BP TP
Megascolecidae
M. houlleti
M. posthuma
P. excavatus
Kanchuria sp 1
K. sumerianus
L. mauritii
A. alexandri
Moniligastridae
D. assamensis
D. p. papillifer
D. nepalensis
Epianecic
Endogeic
Epigeic
Endogeic
Endogeic
Endogeic
Epianecic
Endogeic
Epianecic
Endogeic
+
-
-
+
-
-
-
+
+
-
+
+
+
+
-
+
+
+
+
+
+
-
-
+
-
-
-
+
+
-
+
-
-
+
+
-
-
+
+
+
+
-
-
+
-
+
+
+
+
-
+
-
-
-
-
-
+
+
+
-

14. Earthworms and
family
Categories MFMFP RP PP BP TP
Octochaetidae
E. gigas
E. scutarius
E. comillahnus
Eutyphoeus sp1
E. gammiei
E. assamensis
D. affinis
D. bolaui
O. beatrix
 Glossoscolecidae
P. corethrurus
Ocnerodrilidae
G. elegans
Endoanecic
Endogeic
Endogeic
Endogeic
Endoanecic
Endogeic
Epigeic
Epigeic
Endogeic
Endogeic
Endogeic
+
-
+
-
-
+
+
-
-
+
+
+
+
+
-
+
-
-
-
-
+
-
+
-
+
-
-
+
-
-
+
+
+
+
+
+
+
-
-
-
-
-
+
-
-
-
-
-
-
-
-
+
+
+
-
-
-
-
-
-
-
+
+
+
+
-

15. Fig. 2 Showing different soil physio-chemical parameters in different
monoculture and polyculture plantations (MP – Mixed forest, MFP
– Mixed fruit, RP – Rubber, PP – Pineapple, BP – Bamboo and TP –
Tea plantation)

16. MP MFP RP PP BP TP
50
75
100
125
150
175
200
225

Earthworm density
Earthworm biomass
Types of plantation
E
a
r
t
h
w
o
r
m
d
e
n
s
it
y
(
in
d
m
-
2
)
35
40
45
50
55
E
a
r
t
h
w
o
r
m
b
io
m
a
s
s
(
g
m
-
2
)
MP MFP RP PP BP TP
0.3
0.6
0.9
1.2
1.5
1.8

Richness index
Shannon index
Simpson index
Evenness index
Number of species
Types of plantation
E
c
o
l
o
g
i
c
a
l i
n
d
i
c
e
s
7
8
9
10
11
12
13
14
15
S
p
e
c
i
e
s
r
i
c
h
n
e
s
s
Fig. 2 Showing earthworm density, earthworm biomass and
different ecological indices in different monoculture and
polyculture plantations (MP – Mixed forest, MFP – Mixed fruit,
RP – Rubber, PP – Pineapple, BP – Bamboo and TP – Tea
plantation)

17. 0 200 400 600 80010001200
0
2
4
6
8
10
12
14
16
N
u
m
b
e
r
o
f
s
p
e
c
i
e
s
Number of individuals
Mixed forest
Mixed fruit plantation
Rubber plantation
Pineapple plantation
Bamboo plantation
Tea plantation
0 500 10001500200025003000
0
2
4
6
8
10
12
14
16
18
20
N
u
m
b
e
r

o
f

s
p
e
c
i
e
s
Number of individuals
Polyculture condition
Monoculture condition
(A) (B)
Fig. 3 Showing individual based rarefaction curves
comparing species richness in case of (A) monoculture and
polyculture conditions (B) different studied plantations

18. MegascOctochaMoniligGlossoOcnero
0
10
20
30
40
50
60
70
80
90 Mixed forest
Mixed fruit
Rubber
Pineapple
Tea
Bamboo
R
e
l
a
t
i
v
e
a
b
u
n
d
a
n
c
e
(
%
)
Earthworm families
Fig. 4 Relative abundance of five earthworm families
sampled from different monoculture and polyculture
plantations

19. Hou Pos PeriKancSumerMaurAlex
0
3
6
9
12
15
18
21
R
e
l
a
t
i
v
e
a
b
u
n
d
a
n
c
e
(
%
)
Earthworm species
Mixed forest
Mixed fruit
Rubber
Pineapple
Tea
Bamboo
Fig. 5a Relative abundances of different earthworm species
in different monoculture and polyculture plantations

20. GigScuComiEuty 1GammE. assBolauiAffinisBeatrix
0
1
2
3
4
5
6
7
Mixed forest
Mixed fruit
Rubber
Pineapple
Tea
Bamboo
R
e
l
a
t
i
v
e
a
b
u
n
d
a
n
c
e
(
%
)
Earthworm species
D. assamPapil D. nepaPonto G. ele
0
10
20
30
40
50
60
70
80
Mixed forest
Mixed fruit
Rubber
Pineapple
Tea
Bamboo
R
e
l
a
t
i
v
e

a
b
u
n
d
a
n
c
e

(
%
)
Earthworm species
Fig. 5b Relative abundances of different earthworm
species in different monoculture and polyculture
plantations

23. ACKNOWLEDGEMENTS