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印度加瓦尔喜马拉雅山的亚热带的宽叶榆绿木(Anogeissus latifolia)林恢复状况(英文)



全 文 :Journal of Forestry Research (2010) 21(4): 439−444
DOI 10.1007/s11676-010-0094-z





Regeneration status of a sub-tropical Anogeissus latifolia forest in Garhwal
Himalaya, India

Munesh Kumar • Mukesh Joshi • N. P. Todaria




Received: 2009-09-04 Accepted: 2010-02-23
© Northeast Forestry University and Springer-Verlag Berlin Heidelberg2010

Abstract : The present study deals with the regeneration status of a sub-
tropical forest located between 950−1100 m above sea level in Garhwal
Himalaya. The vegetation was quantitatively analyzed on four different
aspects i.e., east, west, north and south. Results of the study indicated
that across the aspects, Anogeissus latifolia was dominant in tree, sapling
and seedling layers in all the aspects, except north aspect where Pinus
roxburghii and Terminalia tomentosa were dominant in tree and seedling
layers, respectively. The highest tree layer density (380 plant·ha-1) was
recorded on south aspect and lowest (260 plant·ha-1) on west aspect. In
shrub layer, highest density was on east aspect (1790 plant·ha-1) and
lowest on west aspect (970 plant⋅ha-1). Tree and shrub layer diversity
ranged between 0.846 to 1.710 and 1.943 to 2.847, respectively. The
relative lopping intensity (%) was higher in Anogeissus latifolia (45%-
57% as compared to 4%−33% in other species) which is the most impor-
tant tree species on all aspects, except north aspect. The present study
also reveals that if the current rate of exploitation continues, the species
like Anogeissus latifolia may be replaced by other species and drastic
changes may occur in species composition and regeneration of the forest.
The anthropogenic pressure, aspect and soil nutrients have caused
changes in regeneration status and species composition of forests.
Keywords: Anogeissus latifolia; Garhwal Himalaya; tropical; regenera-
tion


Introduction

Garhwal is an integral part of western Himalaya, India (29°
45′−50°0′ N, 78°32′−78°45′E). It is covered with a variety of
forest types varying with altitudes. Within one altitude, the co-
factors like topography, aspect and inclination of slope and soil

The online version is available at http://www.springerlink.com
Munesh Kumar( ) • Mukesh Joshi • N. P. Todaria
Department of Forestry, HNB Garhwal University, Srinagar Garhwal,
Uttarakhand, India. E-mail: muneshmzu@yahoo.com
Responsible editor: Zhu Hong

type affect the forest composition (Shank and Noorie 1950).
With the change in environmental conditions, the vegetation
cover reflects several changes in its structure, density and com-
position (Gaur 1982). The most important structural property of a
community is a definite quantitative relationship between abun-
dant and rare species. The studies on floristic composition and
phytosociological attributes are useful for comparing one com-
munity with the other (Singh 1976).
Regeneration status of trees can be predicted by the age struc-
ture of their populations (Marks 1974; Saxena and Singh 1984;
Khan et al. 1987). The growth status of sufficient number of
seedlings, saplings and young trees indicates a successful regen-
eration of tree population (Saxena and Singh 1984). Regenera-
tion of species is greatly influenced by the interaction of different
biotic and abiotic factors of the environment (Aksamit and Iring
1984). These factors may affect the recruitment, survival and
growth of tree regeneration.
In the Himalayan region, the chronic forms of forest distur-
bances are found in which people remove only a small fraction
of forest biomass. The problem with the chronic form of forest
disturbance is that plants or ecosystems often do not get time to
recover adequately because the human onslaught never stops
(Singh 1998). This does not only affect the ecosystem but also
arrest the succession of the communities.
The present study was conducted to understand the impact of
anthropogenic pressure in term of livestock grazing /browsing,
lopping of trees for firewood and fodder, felling of trees, litter
removal etc. on regeneration status and community composition
of a sub-tropical forest in Garhwal Himalaya.


Materials and methods

Location and climate

Geographically the Garhwal Himalaya is located between
29°319−31° 265N and 70°355−80°6E and exhibited sub-
montane to alpine climates with distinct characteristics of the
specific vegetation types. The present study was conducted in
ORIGINAL PAPER
Journal of Forestry Research (2010) 21(4): 439−444

440
district Tehri Garhwal of a sub-tropical region (latitude 30°29N
and longitude 78°24E) with an elevations ranging from
950−1100 m a.m.s.l., which is 15 km north of Srinagar city of
Garhwal Himalaya. A total of four forest sites, differing in aspect,
were studied to examine the regeneration pattern and community
composition (Table 1). The sites experience a monotonic climate
and can be divisible into three different seasons, viz., rainy (mid
June−September), winter (October−February) and summer
(March−mid June).

Table 1. Site characteristics of study area
Soil texture (%) Forest (average altitude, Above
mean sea level)
Aspect
Anthropogenic
pressure sand silt clay
Organic
carbon (%)
Phosphorus
(kg⋅ha-1)
Potassium
(kg⋅ha-1)
A. latifolia forest (1100 m) East Low 8.9 17.0 74.1 0.48 10.16 162.03
A. latifolia forest (1000 m) West High 5.9 11.9 82.2 0.52 10.36 172.48
P. roxburghii forest (1100 m) North Moderate 7.8 12.7 79.5 0.47 9.67 141.87
A. latifolia forest (950 m) South Low 8.5 11.9 79.6 0.68 10.56 151.57

Vegetation analysis

The phytosociological analysis of tree, sapling, seedling and
shrub layers was done by randomly 10 quadrats of 10m×10m in
size in each site. The size and number of samples were deter-
mined following Saxena and Singh (1982). In each site, the
number of lopped and unlopped trees of each species was noted
down separately in each quadrate to calculate lopping intensity
(%) of each species and relative values were calculated for each
site. The vegetation data were quantitatively analyzed for abun-
dance, density and frequency (Curtis and McIntosh 1950). The
importance value index (IVI) for all the layers was determined as
the sum of the relative frequency, relative density and relative
dominance (Curtis 1959). Trees were considered as individuals
>30 cm c.b.h. (circumference at breast height, 1.37m), saplings
of 10−30 cm c.b.h. and seedlings of <10 cm c.b.h. following
Saxena et al. (1984). The distribution pattern (%) was calculated
following Whitford (1949). The diversity index (H) was calcu-
lated following Shannon and Wiener (1963) method as H=-
∑(ni/n) log2 (ni/n). The concentration of dominance (CD) was
determined by Simpson’s index as (CD) = ∑ (ni/n)2 (Simpson
1949). The H and CD were calculated on the basis of density
values. Dominance-diversity curves were plotted between IVI
and species sequence.


Results and discussion

Soil characteristics

Soil was dominated by clay particles in all the four aspects
(74.1% in east aspect and 82.2% in west aspect; Table 1). Pro-
portion of sand and silt ranged from 5.9 to 8.9 and 11.9 to 17.0,
respectively. Soil pH was acidic in all the four aspects (pH 6.33
to 6.43). The soil organic carbon (0.68 %) and phosphorus (10.56
kg·ha-1) were highest in south aspect while potassium was high-
est in west aspect (172.48 kg·ha-1), (Table 1).

Vegetation analysis

In east aspect, tree layer was dominated by A. latifolia (IVI, 171).
The density and total basal cover of individual species ranged
between 20 (Aegle marmelos, Emblica officinalis) to 230
plant⋅ha-1 (A. latifolia) and < 1 (E. officinalis) to 476 cm2⋅ha-1,
respectively. The total density (Fig. 1), basal cover and species
richness was 370 plant⋅ha-1, 779 cm2⋅ ha-1 and 5, respectively.
Similarly, sapling and seedling layers were dominated by A.
latifolia. Sapling and seedling density ranged between 20−240
and 40−200 plant⋅ha-1, respectively (Table 2). In shrub layer,
Indigofera gerardiana (IVI-43) was dominant with highest den-
sity and basal cover. Shrub layer species richness was 9 (Fig. 1).
In west aspect, A. latifolia was dominant species with highest
IVI (114) and basal cover (138 cm2⋅ha-1). The total density and
basal cover were 260 plant⋅ha-1 and 506 cm2⋅ha-1, respectively.
Sapling and seedling layers were dominated by A. latifolia. In
shrub layer, Carrisa spinarum was dominant species (IVI, 88).
Pinus roxburghii was dominant tree species in north aspect
with highest IVI (225). The total basal cover was 1073 cm2⋅ha-1,
about 90% of the total basal cover was contributed by P. rox-
burghii in this aspect. Sapling and seedling layers were domi-
nated by A. latifolia (Table 2). In shrub layer, C. spinarum was
dominant species (IVI, 71).

9
555
6
3
5
4
6
23
3
5
2
43
0
500
1000
1500
2000
Tree Sapling Seedling Shrub
Species layer
D
en
si
ty
(p
la
nt
·h
a-1
)
East West North South

Fig. 1 Total density (bars) and species richness (numbers in bars) for
trees, saplings, seedlings and shrubs in different aspects

In south aspect, A. latifolia was dominant species (IVI, 223).
Other two species were Lannea coromendalica (IVI, 56) and T.
tomentosa (IVI, 21). The total basal cover was 1003 cm2⋅ha-1.
Sapling and seedling layers were dominated by A. latifolia (Ta-
ble 2). In shrub layer, Rhus parviflora was dominant species (IVI,
82).
Across the four aspects, the highest density of tree layer (380
Journal of Forestry Research (2010) 21(4): 439−444

441
plant⋅ha-1) was in south aspect and the lowest (260 plant⋅ha-1) in
west aspect (Fig. 1). The total basal cover (TBC) for tree layer
ranged between 1 073.1 cm2⋅ha-1 (north aspect) and 505.7cm2·ha-
1 (west aspect). These values were lower than the values reported
by different workers for density (350 to 2 080 trees⋅ha-1) and
TBC (1 561 to 5 931 cm2⋅ha-1) for temperate forest of Central
Himalaya (Saxena and Singh 1982). This may be due to selective
felling of tree species by the local villagers for various purposes
(fodder, fuel, agricultural implements, etc). Khera et al. (2001)
have also reported lower total basal cover values (450 to 1 680
cm2⋅ha-1) for disturbed oak forest of Central Himalaya.
In shrub layer, the highest density value (1 790 plant⋅ha-1) was
in east aspect and lowest (970 plant⋅ha-1) in west aspects (Fig. 1).
The total maximum TBC for shrub layer was 4.4 cm2·ha-1 in east
aspect, and the minimum (1.8 cm2·ha-1) in north aspect. Agni-
hotri et al. (2006) indicated that aspect and physiographic posi-
tions, particularly on hills are expected to influence vegetation
cover. This is because the south and east facing slopes have early
sun shine of the day, while north and west aspects receive sun
during the later parts of the day. Therefore, south aspect had total
highest density of trees and east aspect could be favorable for the
better growth of shrubs among the aspects as indicated total
highest density (1790 plant·ha-1). The shrub layer density and
TBC values of the present study were lower than the range val-
ues reported for sub-tropical region of Garhwal Himalaya (2 760
to 2 999 plant⋅ha-1 for density and 65 to 135 cm2·ha-1 for TBC),
(Kumar et al. 2004). The lower values seems to be related to the
variety of factors viz., grazing/browsing and trampling by live-
stock, burning of ground litter during summer to increases pro-
ductivity of ground vegetation, collection of firewood, etc.

Table 2. Density (plant⋅ha-1), total basal cover (cm2⋅ha-1) and IVI of saplings and seedlings in different aspects
East West North South
Species
Density TBC IVI Density TBC IVI Density TBC IVI Density TBC IVI
Sapling
Anogeissus latifolia 240 66 143.56 320 71 153.57 90 27 129.56 320 55 199.93
Aegle marmelos 50 15 35.10 - - - - - - - -
Ougeinia oojenensis 110 24 58.92 - - - - - - - - -
Lannea coromandelica 20 14 18.86 120 29 64.79 - - - 30 14 40.76
Emblica officinalis 60 24 43.86 - - - - - - - -
Acacia catechu - - - 40 11 28.66 - - - 40 12 45.87
Pinus roxburghii - - - 40 23 36.25 70 40 119.99 - - -
Bauhinia veriegata - - - 30 3.0 16.71 - - - - - -
Terminalia tomentosa - - - - - 40 10.6 50.44 10 5.0 13.43
Seedling
Anogeissus latifolia 200 2 141.81 50 0.6 154.32 100 2.0 132.09 100 3.0 244.20
Aegle marmelos 40 0.3 29.03 20 0.2 86.82 - - - - - -
Ougeinia oojenensis 90 0.4 49.09 - - - - - - - -
Lannea coromandelica 50 1.0 44.00 - - - - - - 20 0.3 55.80
Emblica officinalis 50 0.2 36.06 - - - - - - - - -
Bauhinia veriegata - - - 10 0.3 58.86 - - - - - -
Terminalia tomentosa - - - - - - 110 2.0 167.91 - - -

In sapling layer, Anogeissus latifolia was dominant in all the
aspects with highest values of IVI, density and TBC. The least
dominant species were Lannea coromandelica (IVI=18.86),
Bauhinia variegata (IVI=16.71) and Terminalia tomemtosa
(IVI=13.43) in east, west and south aspects respectively. Simi-
larly in the seedling layer, A. latifolia was recorded to be domi-
nant in all the aspects. The maximum and minimum values of
IVI of A. latifolia among the aspects were 244.20 (south) and
132.09 (north) (Table 2), respectively.
Across the aspects, highest total density (430 plant⋅ha-1) for
seedling and highest total basal cover (143 cm2⋅ha-1) for sapling
layers were recorded in east aspect. The earlier sunshine and low
anthropogenic pressure in east aspect might be favourble for the
growth of regeneration. Boring et al. (1981) have also empha-
sized the positive role of mild disturbances in improving the
regeneration of trees. The species reported in the study area are
frequently used by the local villagers for their basic demand
(Table 3).
Population structure of a species in a forest can convey partly
its regeneration behaviors, in relation to the reproductive strategy.
Importance is given to the number of saplings under adult tree
for predicting future composition of a forest community. The
long history of human interaction with plant, animals and envi-
ronment in the mountain region has a significant impact upon the
biological diversity at different levels. The topography, soil,
climate and geographical location influenced the vegetation di-
versity of forest. The greater diversity in the floristic pattern due
to altitudinal variation coupled with rainfall has been well docu-
mented (Bisht and Lodhiyal 2005). In recent, years the Central
Himalayan forest ecosystems have witnessed the great natural as
well as biotic disturbances. These disturbances do not provide
time for the ecosystem recovery and arrest the regeneration of
the forest species (Singh 1998).
The lower population of tree seedlings (80 plant·ha-1) in west
aspect and especially of A. latifolia (50 plant⋅ha-1 as compared to
100-200 plant⋅ha-1 in other aspects) may be due to heavy anthro-
pogenic pressure on the overstory species for fuel, fodder and
other basic requirements of the villagers which affect the seed
production of trees.
Journal of Forestry Research (2010) 21(4): 439−444

442
Table 3. Tree species in different aspects and ecosystem service to local people
Species Vernacular name Family Ecosystem services to local people
Anogeissus latifolia Wall ex.D.Don Dhau Combretaceae Fodder, fuel, timber, gum, agricultural implements
Terminalia tomentosa (Roxb.) Wight &Arn. Asin Combretaceae Fodder, fruit for local medicine
Emblica officinalis Gaertne Anwala Euphorbiaceae Fruits are used for prickle, local medicine
Acacia catechu (L.f.) Willd. Khair Fabaceae Fuel, fodder for goat in forest
Ougeinia oojeinensis Hochr. Sandan Fabaceae Wooden utensils/fodder/flower for vegetable
Aegle marmelos (L.) Corrêa Bel Rutaceae Medicine
Lannea coromandelica (Houttuyn) Merrill Kalmina Anacardiaceae Agricultural implements, firewood
Pinus roxburghii Sargent Chir-pine Pinaceae Fuel wood


Distribution pattern (%)

The distribution pattern of the species in the different layers and
aspects has been given in Fig. 2a-d. Among the aspects, the most
tree species were distributed randomly and few species were
distributed regularly in all aspects except west (Fig 2a). The
contagious distribution for tree layer was found only in west and
north aspects. In sapling layer, majority of species were distrib-
uted contagiously, few species were random in distribution and
no species was found in regular distribution in all aspects (Fig.
2b) except east aspect. In seedling layer, the contagious distribu-
tion of species was dominant in all aspects except in south aspect
where species distribution pattern (Fig. 2c) was random (100%).
Similarly for shrubs, the contagious distribution was most com-
mon, (Fig. 2d).



Fig. 2 Distribution pattern of trees (a), saplings (b), seedlings (c) and shrubs (d) in different aspects

Regular and random distribution pattern of species reflect the
higher biotic pressure in terms of grazing and lopping in natural
forest stands. Odum (1971) stated that clumped (contagious)
distribution is the commonest pattern in nature, and random dis-
tribution is found only in very uniform environment and the
regular distribution occurs where severe competition between the
individuals exists (Panchal and Pandey 2004). Contagious distri-
bution may be related to seed dispersal mechanism of the species
and gap formation (Barik 1996; Kersaw 1973; Singh and Yadav
1974; Greig Smith 1957). Mehta et al. (1997) also reported ran-
dom and contagious distribution pattern of species in various
forests of the Garhwal Himalaya.

Species diversity (H) and concentration of dominance of concen-
tration (CD)

The CD and H values of different layers of forest on different
aspects are indicated in Fig. 3a-d. The ranged values of diversity
for trees (0.846 in south-aspect to 1.710 in west-aspect) and
shrubs (1.943 in west-aspect to 2.847 in east-aspect) of present
study were comparable with the reported values for temperate
(Adhikari et al. 1991; Bhandari et al. 2000) and sub-tropical
(Kumar et al. 2004) forests. Similarly, the range values of CD for
trees (0.326 to 0.693) and shrubs (0.185 to 0.719) are within the
Journal of Forestry Research (2010) 21(4): 439−444

443
range (0.10−0.99) reported by various works (Risser and Rice
1971; Knight 1975). The H and CD of saplings and seedlings in
various aspects (east, west, north and south) are given in Fig. 3.
The highest diversity among the aspects for sapling layer was in
east aspect (1.520), whereas, the lowest in south aspect (1.10).
Value of diversity in west and north aspects was 1.309 and 1.146,
respectively. The maximum and minimum values of diversity in
seedling layer were 1.435 and 0.496 in west and north aspects,
respectively. The highest (0.655) and lowest (0.331) values of
CD for sapling layer were recorded in south and east aspects,
respectively. The range values of CD for seedling layer were
0.294 (east-aspect) to 0.722 (south-aspect).

Dominance diversity (d-d) curve

Dominance-diversity curves were developed for trees, saplings,
seedlings and shrubs (Fig. 4a-d). The dominance-diversity (d-d)
curve approaches a geometric series for the trees. Mostly the
curve follows the geometric series in conformity with niche pre-
emption hypothesis (Motonura 1934). The geometric form is
often shown by vascular plants having lower density (Whittaker
1975).


















Fig. 3 Diversity (H) and Concentration of dominance (CD) of trees (a), saplings (b), seedlings (c) and shrubs (d) in different aspects


















Fig. 4 Dominance-diversity curves for trees (a), saplings (b), seedlings (c) and shrubs (d) in different aspects

Anthropogenic pressure

The anthropogenic pressure in terms of uncontrolled or selected
felling, lopping of trees for firewood and fodder, livestock graz-
ing/browsing, litter removal, etc. was low in east and south as-
pects, moderate in north aspect and high in west aspect (Table 1).
The density of seedlings was low in west aspect (80 plant·ha-1),
compared to other aspects (120−430 plant⋅ha-1). Across the as-
pects, A. latifolia showed dominance in tree, sapling and seedling
layers in all the aspects, except north aspect where Pinus rox-
burghii and Terminalia tomentosa were the dominated tree and
seedling layers, respectively. The relative lopping intensity (%)
b
0
0.5
1
1.5
2
2.5
Tree Sapling Seedling Shrubs
Layer (West)
H
0
0.1
0.2
0.3
0.4
0.5
C
D
H CD
a
0
0.5
1
1.5
2
2.5
3
Tree Sapling Seedling Shrubs
Layers (East)
H
0
0.2
0.4
0.6
0.8
C
D
H CD
c
0
0.5
1
1.5
2
2.5
Tree Sapling Seedling Shrubs
Layer (North)
H
0
0.2
0.4
0.6
0.8
C
D
H CD d
0
0.5
1
1.5
2
2.5
Tree Sapling Seedling Shrubs
Layer (South)
H
0
0.2
0.4
0.6
0.8
C
D
H CD
c
0
50
100
150
200
250
300
1 2 3 4 5 6 7 8
Species sequecne 1...n
Im
po
rta
nc
e
va
lu
e
in
de
x
East
West
North
South
a
0
50
100
150
200
250
1 2 3 4 5 6 7 8 9 10
Species sequecne 1....n
Im
po
rta
nc
e
va
lu
e
In
de
x
East
West
North
South
b
0
50
100
150
200
250
1 3 5 7 9 11 13
Species sequecne 1...n
Im
po
rta
nc
e
va
lu
e
in
de
x
East
West
North
South
d
0
20
40
60
80
100
120
1 3 5 7 9 11 13 15
Species sequecne 1...n
Im
po
rtn
ac
e
va
lu
e
in
de
x
East
West
North
South
Journal of Forestry Research (2010) 21(4): 439−444

444
values for tree species in different sites showed that anthropo-
genic pressure in terms of lopping of trees was very high in all
the sites. All the species were lopped by the villagers, however,
the intensity of lopping on different species varies across the
sites (Table 4). The relative lopping intensity (%) was higher in
A. latifolia (45%−57%) as compared to 4%−33% in other species)
which is the most important tree species on all the aspects, ex-
cept north aspect where Pinus roxburghii showed his dominance.
The results of present study indicate that A. latifolia which is
very important in providing various ecosystem services to local
people, may be replaced by some other species and drastic
changes may occur in species composition and regeneration of
the forest.
Table 4. Importance value index (IVI) and relative lopping intensity
(RLI, %) of tree species in different aspects
East West North South Species
IVI RLI IVI RLI IVI RLI IVI RLI
Anogeissus latifolia 171 52 114 57 48 49 223 45
Aegle marmelos 18 4 - - - - - -
Emblica officinalis 15 4 - - - - - -
Ougeinia oojeinensis 29 11 - - - - - -
Lannea coromandelica 67 29 92 20 - - 56 33
Pinus roxburghii - - 83 10 225 23 - -
Acacia catechu - - - - - - - -
Terminalia tomentosa - - 11 13 27 28 21 22

Acknowledgements
Authors are thankful to Dr S.S. Samant, GBPIHED, Kulu, HP
for his critiques and comments.

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