Vegetation analysis and differences in local environment variables in indrawati hydropower project areas in Nepal

Abstract

Vegetation covering an area has a definite structure and composition developed as a result of long term interaction with biotic and a biotic factors, and any change in the status of these factors disturbs the floristic composition of the environment. Five quadrates with sampling size of 20 X 20m 2 in 0.02 ha. area was selected for analysis of vegetation to quantify species diversity, composition, size class distribution and dominance of the species. A total of 387 tree individuals, representing 33 species, 32 genera and 23 families were recorded. Total stand density and basal area were, respectively, 638.55 trees ha−1 and 17.68 m2ha−1 in five plots. The highest IVI value was that of Alnus nepalensis (30.21) followed by Castanopsis tribuloides (21.22) and Lyonia ovalifolia (19.27) in plot 3 where the Dbh of tree was <10cm. Based on IVI values, Alnus nepalensis, Castanopsis tribuloides, and Lyonia ovalifolia were found to be the most dominant species in the study area. The three values as 0.09333, 0.9066 and 10.71 of Simpsons Diversity (D) of 33 species represent different biodiversity. The plot 3 of natural forest and plot 4 and 5 along the project area has found significantly deceasing number of species.

Full text

Page 1

International Research Journal of Plant Science (ISSN: 2141-5447) Vol. 1(4) pp. 083-094, October, 2010
Available online http://www.interesjournals.org/IRJPS
Copyright © 2010 International Research Journals


Full Length Research Paper

Vegetation analysis and differences in local
environment variables in indrawati hydropower
project areas in Nepal

Ramesh Prasad Bhatt and Sanjay Nath Khanal

Department of Environmental Science and Engineering School of Science, Kathmandu University Kathmandu,
Nepal

Accepted 13 September, 2010

Vegetation covering an area has a definite structure and composition developed as a result of long
term interaction with biotic and a biotic factors, and any change in the status of these factors disturbs
the floristic composition of the environment. Five quadrates with sampling size of 20 X 20m2 in 0.02 ha.
area was selected for analysis of vegetation to quantify species diversity, composition, size class
distribution and dominance of the species. A total of 387 tree individuals, representing 33 species, 32
genera and 23 families were recorded. Total stand density and basal area were, respectively, 638.55
trees ha−1 and 17.68 m2ha−1 in five plots. The highest IVI value was that of Alnus nepalensis (30.21)
followed by Castanopsis tribuloides (21.22) and Lyonia ovalifolia (19.27) in plot 3 where the Dbh of tree
was <10cm. Based on IVI values, Alnus nepalensis, Castanopsis tribuloides, and Lyonia ovalifolia were
found to be the most dominant species in the study area. The three values as 0.09333, 0.9066 and 10.71
of Simpsons Diversity (D) of 33 species represent different biodiversity. The plot 3 of natural forest and
plot 4 and 5 along the project area has found significantly deceasing number of species.

Key words: Vegetation Analysis, Indrawati III Project, Environmental Variables, Change and Impact, Species
Diversity, Community forests


INTRODUCTION

Forest and vegetation of particular ecosystem
generally influenced by the external factors especially
the man made development activities. For along time it
was believed by some ecologists like Clements (1916),
Braun-Banquet (1932) and Odum (1971), that
vegetation is composed of certain distinct and fairly
discrete plant communities. This view regards
communities as having a degree of internal
organization which jointly modifies the environment
with sharp delimitation from other communities (Odum,
1971).
The composition of plant structures is closely
associated with the biotic and abiotic environmental
factors which make sudden changes due to external
factors of disturbances. The current vegetation reflects
the site conditions and disturbances over time. Hence,


*Corresponding author Email: rameshbhatta@yahoo.com
hemeroby concept (Jalas, 1955; Sukopp, 1969;
Kowarik, 1988, 1990) was developed for estimating
environmental change at a given site using the
difference of current vegetation in comparison with the
pristine or potential natural vegetation. However, use
of that method is flawed because one can not find a
pristine ecosystem in this changed and changing
world, because of the complex and nonlinear nature of
ecosystems and unique ecological histories. Thus,
vegetation that is completely “natural” and pristine, as
well “potential natural” is hypothetical (Reif, 2000).
Moreover, that method can not be used for a cross-
scale evaluation because the species number found
depends on the plot size studied (i.e. species-area
relationship).
Composition and distribution pattern of vegetation
and forest types and differences of local environmental
variable in the Indrawati III Hydropower project area
was studied with extensive literature (GoN/ Earth
Science 1984, Science, G. E. 1984), Stainton, 1972)

Page 2

084 Int. Res. J. Plant Sci.



and collection/measurement of field data’s.
The frequency of vegetation components, density
and volume of trees in actual impact areas such as
above intake-dam site (Haryali CF), Audit-C (Golma
Raja Golma Rani CF), above Penstock (Golma Raja
Golma Rani CF), Penstock and Powerhouse site were
analyzed by quadrate sampling in representative
transect stands at selected sampling sites.
Impacts produced by the implementation of power
sector projects may degrade forest resources,
including local ecology and ecosystems, and can
eventually affect the sustainability of project benefit.
Therefore, Environmental Impact Assessment (EIA) of
Indrawati Hydropower project was conducted in 2002
as per Environmental Protection Regulation (EPR)
1997, Government of Nepal (GoN/MoLJPA 1996).
Since the project operation
implementation of EIA in order to make projects more
environmentally sound, sustainable, and socially
beneficial (GoN, MOE, NHC. 2002), this research
illustrate the change in local environment with
emphasis of quantitative analysis of forest and
vegetation and change in environmental gradients
through project operation.


MATERIAL AND METHODS


Study Area

The study area is located between 27º36'-28 º 13’ north
longitudes and 85º27'-86º16' east latitudes Sindhupalchowk
district in Nepal. The district has an extent area of about 27km2
(2710ha.) with elevation ranging from 1020m at the confluence
of Harikhola and Indrawati known.
Physiographically, Indrawati river basin lies subtropical Tar
besi region with elevation range from 850m asl to above. The
catchments area of the Indrawati River is 437sq.km. The
Indrawati watershed has good density of natural forests with
crown cover of more than 70% occupy only 1.8% of the district
mainly at the upper ridges of Indrawati watershed (Dobromez,
1974).
Out of total 25.3 m3/s total discharges in the river the Indrawati
III Hydropower Project is operating with its design discharge of
14.3m3/sec for 7.5 MW power generations. The average annual
rainfall of the project area is 2537.35mm and relative humidity
ranges from 75 to 95% over the year. Maximum temperature
recorded in the project area is 30º Celsius and minimum is 10º
Celsius. The project area along with 5km long access road
surrounded by river valley, community forest, cultivated land,
barren land and settlements. The study was carried out in the
forests of project influence area. Figure.1


Methods

Field study was carried out in April 2010 by measuring five plots
an area of 200 sq.m size (0.02 hectare) in and around of
Indrawati Hydropower project influence area. The five plots were
measured in different disturbed and undisturbed forest patches
like above dam site (Haryali CF), Above Audit C, above
Penstock (Golma Raja Golma Rani CF), Penstock area and
in 2004 and




Powerhouse site. The quadrate size (20m x 20m2) was randomly
demarcated for study. The vegetation was analyzed by adopting
releve analysis approach (Dombosis and Ellenberg, 1974). The
Plant species of all growth forms within each quadrate were
enumerated by using a simple matrix. The diameter at breast
height and height of each trees including cut stumps, having
more than 10cm circumference were measured.
Density, frequency, basal area and their relative values and
importance value index (IVI) of tree species were calculated
following Mueller-Dombosis and Ellenberg (1974). Botanical
name and author citation was made following Government of
Nepal, Department of Plant Resources (DPR) 2001 and
Dictionary of Nepalese Plant Names (K. Shrestha 1998). In
addition to quantitative data, interviews and group discussions
was conducted to collect information relating to community forest
management. In order to assess the general condition and
vegetation pattern of the forest, a density-diameter histogram
was developed. Girth of trees exceeding 10cm diameter at
breast height was measured. The height of standing trees was
measured by means of a hypsometer. The species area curve of
each community forests was calculated by randomly adding up
the number of tree species in each quadrate. The dominance
diversity curve (D-D curve) was used in order to ascertain the
resource apportionment among the various species at various
sites.
Coefficient (J) (Jaccard’s P, 1912) was used to quantify the
extent to which family and species composition overlapped
between sample sites. It is defined as: J = A /(A + B + C) where
A is the number of family and species found in three sites, B is
the families and species in site 3 but not in site 2, and C is the
families and species in site 3 but not in 2.
‘S,’ or species richness, was determined following (Whittaker,
1976) by tabulating the number of woody species in each plot.
Shannon-Weiner’s diversity index ‘H’ (Shannon and Weiner
1963), concentration of dominance ‘D’ (Simpson, 1949) and Hill
diversity numbers N0, N1 and N2 (Hill 1973) were computed.
Simpson’s index ‘D’ was calculated using the formula ‘D’ = 1 -
Σpi2, where pi is the relative density. Shannon-Weiner’s diversity
index ‘H’ was calculated using the formula ‘H’ = - Σpi Log pi,
where pi represents the proportional abundance of the species in
the community. Hill diversity indices were calculated using the
following formulae:
Number 0: N0 = S, where S is the total number of species;
Number 1: N1 = eH, where ‘H’ is the Shannon’s index;
Number 2: N2 = 1/D, where ‘D’ is Simpson’s index


RESULTS


Species area curve

The slope of the species area curve for each study site
declined as sample area increased but did not
approach an asymptote (Figure 2).


Vegetation composition

A total of 387 tree individuals, representing 33 species,
32 genera and 23 families, were identified within the
0.2 ha area of the study (Table 1). Eight species i.e.
Entada phaseolodies (Leguminosae), Fraxinus

Page 3

Khan et al. 085




Figure 1. study area



flribunda (Oleaceae), Hedyotis scandens (Rubiaceae),
Indigolera pulchella (Leguminosae), Pegia nitida
(Anacardiaceae), Pyrus pashia (Rosaceae), Rosa
burnonii (Rosaceae), Smilax aspera (Laliaceae) were
found only above dam site (Haryali Community Forest)
in plot 1. Two species, Aesandra butyracea
(Spotaceae) and Terminalia alata (Combretaceae)
were found above Audit C (Golma Raja Golma Rani
CF) in plot 2. Three species, Osyris wightiana
(Santalaceae), Rubus ellipticus (Rosaceae) and Rhus
javanica (Anacardiaceae) were found only in above
penstock (Golma Raja Golma Rani CF) in plot 3 (Plot 3
represents saplings of regenerated forest species less
than 10cm dbh. This was the forest cleared area of




Golma
construction.
),
(Dipterocarpaceae) was found in plot 4 (Plot 4
represents planted saplings of forest species and
naturally regenerated saplings of Alnus nepalensis and
Lyonia ovalifolia less than 10cm dbh. In this area
circular Surge shaft (Tank) with 30m height and 600m
long penstock with 2.3 m diameter is located.
) Penstock area and three species, Dalbergia sissoo
(Leguminosae), Mangifera indica (Anacardiaceae) and
Zanthoxylum armatum (Rutaceae) were found in plot 5
powerhouse sites respectively. (Table 1).
Among the 33 species 28 species were calculated
Raja Golma Rani CF during project
Single species of
Shorea robusta

Page 4

086 Int. Res. J. Plant Sci.



0
10
20
30
40
50
60
0500 100015002000 2500
Area (m2)
Species


Figure 2. Species area curve


















Figure 3: Distribution of tree in different size class



for density and basal area. Total stand density and
basal area were, respectively, 638.55 trees ha−1 and
17.68 m2ha−1 in five plots (Table 2 and 3). Girth sizes
of trees at breast height (gbh) ranged from 10 to 170
cm in five plots. The greatest gbh of Bombex cebia
(170 cm) was found in plot 1 followed by Schima
wallichii (160 cm). The greatest heights (>20 m) of tree
species,
Engelhardia spicata,
Bombax ceiba, Engelhardia spicata and Castanopsis
tribuloides, were observed only in plot 1.
The highest IVI value was that of Alnus nepalensis
(30.21) followed by Castanopsis tribuloides (21.22)
and Lyonia ovalifolia (19.27) in plot 3 where the dbh of
tree are <10cm. The plot 3 was identified disturbed
area of natural forest. There were regenerated
saplings of tree species as forest was felled during
construction period of the project. Based on IVI values,
Alnus nepalensis, Castanopsis tribuloides, and L.
ovalifolia were found to be the most dominant species
in the study area (Table 3). 6.6% of the total
Schima
wallichii,
individuals of Pyrus pashia were observed cut stumps
in plot 1 and 3.3% Terminalia alata were in plot 2
respectively.

Size class distribution

The distribution of Gbh classes conformed to an
reverse ‘J’ shape curve, with 50% of individuals having
Gbh between <70 cm: 17.86% individuals of 51-60 cm
Gbh , 10.71% individuals of 31-40 cm, 7.14 of each 10-
20cm and 41-50cm and rest 3.57% in each 21-30 cm
and 61-70 respectively (Figure 3). The number of
individuals with a diameter greater than 70 cm was 9
(64.28%) in plot 1, 3 (21.42%) in plot 2 and 2 (14.28%)
in plot 4, totaling 50% of total species (Figure 3).

Dominance diversity curve

Species dominance related to the availability of
suitable niche and resource apportionment in a
0
10
20
30
40
50
60
70
80
>7061-7051-60 41-5031-40 21-30>10
Diameter class (cm)
S ta n d D e n sity tre e s/h a

Page 5

Khan et al. 087



Table 1. Composition and distribution of forest species in Five Sampling Plots

SN
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
Total
Scientific Name
Aesandra butyracea
Alnus nepalensis
Bombax ceiba (L.)
Caesalpinia decapitala
Callicarpa macrophylla
Castanopsis tribuloides
Citrus maxima
Cleistocalyx operculata
Dalbergia sissoo
Engelhardia spicata
Entada phaseolodies
Fraxinus flribunda
Gaultheria fragrantissima
Hedyotis scandens
Hedyotis scandens
Indigolera pulchella
Lyonia ovalifolia
Mangifera indica
Osyris wightiana
Pegia nitida
Pyrus pashia
Rhus javanica
Ribes takare
Rosa burnonii
Rubus ellipticus
Sapium insigne
Schima wallichii
Seteria genniculata
Shorea robusta
Smilax aspera
Terminalia alata
Toona cialita
Zanthoxylum armatum
Local Name
Churi
Utis
Simal
Arile kanda
Guaili
Katus
Bhogate
Kyamuna
Sisau
Mawa
Pangra
Lakure
Dhasingare
Dhudhe lahara
Bokrelahara
Phusareghans
Aingire
Anmp
Nundhiki
Chutilahara
Mayal
Bhakmilo
Dhursurlo
Bhainsi kanda
Ainselu
Khirro
Chilaoone
Kagune jhar
Sal
Kukurdiano
Saj
Tooni
Timur
Family
Spotaceae
Betulaceae
Bombacaceae
Leguminosae
Verbenaceae
Fagaceae
Rutaceae
Myrtaceae
Leguminosae
Juglandace
Leguminosae
Oleaceae
Ericaceae
Rubiaceae
Rubiaceae
Leguminosae
Ericaceae
Anacardiaceae
Santalaceae
Anacardiaceae
Rosaceae
Anacardiaceae
Gross
Rosaceae
Rosaceae
Euphorbiaceae
Theaceae
Gramineae
Dipterocarpaceae
Laliaceae
Combretaceae
Meliaceae
Rutaceae
Sampling Plots
1 2
- +
- +
+ +
+ +
- +
+ +
+ -
- +
- -
+ +
+ -
+ -
+ +
+ -
+ -
+ -
- +
- -
- -
+ -
+ -
- -
+ +
+ -
- -
- +
+ -
+ +
- -
+ -
- +
+ -
- -
19 14
Total
1
4
3
2
1
4
1
2
1
4
1
1
2
1
1
1
3
1
1
1
2
1
2
1
1
2
3
2
1
1
1
2
1
56
3
-
+
+
-
-
+
-
-
-
+
-
-
-
-
-
-
+
-
+
-
+
+
-
-
+
-
+
-
-
-
-
+
-
11
4
-
+
-
-
-
+
-
+
-
+
-
-
-
-
-
-
+
-
-
-
-
-
-
-
-
+
-
-
+
-
-
-
-
7
5
-
+
-
-
-
-
-
-
+
-
-
-
-
-
-
-
-
+
-
-
-
-
-
-
-
-
+
-
-
-
-
-
+
5

Note: + = Presence, - = Absence


community has often been interpreted from the
dominance diversity curve (D-D curve). D-D curves for
sampling plots 4 (Figure 4) were found consistent with
the normal distribution model of Preston (FW, 1948),
i.e., relatively few species had a high IVI. These curves
illustrate resource partitioning among the various
species (Verma et. al, 2001).

Species diversity

Table 4 depicts the plant species richness, Shannon-
Weiner diversity index, Simpson’s diversity index,
Jaccard’s coefficient and Hill’s diversity index of five
sampling plots in different forest patches of project
area. Maximum species richness (19) was observed in
plot 1 above dam site (Haryali CF) while the minimum
(5) in plot 5 powerhouse site. This result proves that
the disturbance of development activities in natural
forest reduce the species diversity.
The adjusted Shannon-Wiener Index is the percent
of the maximum possible diversity. The maximum is
the in ("Total Number of Species"): 3.497. The
Shannon-Weiner diversity index was 2.372 in sample
plots, while the concentration of dominance Simpson
diversity index for sampling was 78.14%. Jaccords,
coefficient (J) was 0.37. Hill diversity numbers N0, N1
and N2 were 19, 17.92 and 1.071 respectively (Table
4).
The three different value of Simpsons Diversity (D)
of 33 species were 0.09333, 0.9066 and 10.71 (Table
4 and 5) represents the different biodiversity.


DISCUSSION

While square plots are usually superior for correlating
plant communities with local environmental variables
(Ferreira and Merona, 1998), various shapes and sizes

Page 6

088 Int. Res. J. Plant Sci.



Table 2: Basal Area and Volume of Trees species in each Sampling Plot

Quadrate –I (Above Dam Site-Haryali Community Forest)
SN
1
Scientific Name
Engelhardia spicata
Castanopsis
tribuloides
Engelhardia spicata
Schima wallichii
Schima wallichii
Toona cialita
Castanopsis
tribuloides
Nepali Name
Mawa
Family
Juglandace
Girth
(cm)
140
Height
(m)
30
BA (m2)
1.539
Volume
(m3)
23.079
2
3
4
5
6
Katus
Mawa
Chilaoone
Chilaoone
Tooni
Fagaceae
Juglandace
Theaceae
Theaceae
Meliaceae
40
90
60
116
80
5
20
20
45
12
0.1256
0.636
0.283
0.950
0.5024
0.314
6.36
2.826
21.372
3.0144
7 Katus Fagaceae 50 10 0.196 0.98125
8
Bombax ceibaL.
Castanopsis
tribuloides
Schima wallichii
Schima wallichii
Schima wallichii
Schima wallichii
Schima wallichii
Engelhardia spicata
Quadrate II-Audit C (Golma Raja Golma Rani Community Forest)
1
Terminalia alata
Saj
2
Terminalia alata
Saj
3 Aesandra butyracea Churi
4
Terminalia alata
Saj
5
Terminalia alata
Saj
Cleistocalyx
operculata
Kyamuna
7
Terminalia alata
Saj
8
Terminalia alata
Saj
9
Terminalia alata
Saj
10
Terminalia alata
Saj
Quadrate V- Powerhouse Site
1
Schima wallichii Chiloone
2
Magnifera indica
Anmp
3
Delbergia sisoo Sisoo
Simal Bombacaceae 170 70 2.269 79.403
9
10
11
12
13
14
15
Katus
Chilaoone
Chilaoone
Chilaoone
Chilaoone
Chilaoone
Mawa
Fagaceae
Theaceae
Theaceae
Theaceae
Theaceae
Theaceae
Juglandace
1.25
55
110
48
160
60
110
25
8
3
18
85
15
25
1.1304
0.237
0.950
0.181
2.01
0.2826
0.950
14.13
0.94985
1.425
1.6278
85.408
2.1195
11.873
Combretaceae
Combretaceae
Spotaceae
Combretaceae
Combretaceae
80
70
30
100
60
12
15
15
10
12
0.5024
0.38465
0.07065
0.785
0.2826
3.0144
2.884875
0.529875
3.925
1.6956
6 Myrtaceae
Combretaceae
Combretaceae
Combretaceae
Combretaceae
20
80
60
50
40
5
12
11
9
7
0.0314
0.5024
0.2826
0.19625
0.1256
0.0785
3.0144
1.5543
0.883125
0.4396
Theaceae
Anacardiaceae
Leguminosae
80
150
10
12
13
11
0.5024
1.76625
0.007875
3.0144
11.48063
0.043313

Transect III and IV represents tree saplings and shrub species less than 10cm dbh.



of plots have been selected for other studies (Table 6).
In Nepal, most studies designed for the study of
diversity or family/species abundance (including the
present) have employed square sample plots.
Comparison of quantitative data from the present study
to those collected at other forest sites has been shown
in Table 6.
For all surveyed sites, the slope of the curve relating
species and area declined as sample area increased.
The species area curves for plots were more or less
consistent with a gradual decrease in the number of
species with area, initially down to 50 m2, and then
appears to be approaching an asymptote indicating
that the sampled area of penstock and powerhouse
area is inadequate for specific forest (Figure 1). It can
be argued that, for sample plots at penstock and

powerhouse
inadequate. Thus, the project area near powerhouse
and penstock area was not found forested activities
and disturbed by the project and other anthropogenic
activities.
The other three plots in Community forests one in
Haryali CF and two in Golma Raja Golma Rani CF)
have controlled forest management activities. The
Haryali Community Forest located around intake and
access road site covers an area of 95ha which was
handed over as community forest in 2051/052 BS. The
Golma Raja Golma Rani Community Forest covering
an area of 48 ha was handed over in 2052/053 BS.
These community forest management runs under
users’ forest operational plan and forest Act which
guides and regulates forest management. Despite the
site covering half hectares are

Page 7

Khan et al. 087



Table 3: Frequency, Relative frequency, Relative Density, Relative Dominance and Importance Value

SN
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
Scientific Name
Aesandra butyracea
Alnus nepalensis
Bombax ceiba (L.)
Caesalpinia decapitala
Callicarpa macrophylla
Castanopsis tribuloides
Citrus maxima
Cleistocalyx operculata
Dalbergia sissoo
Engelhardia spicata
Entada phaseolodies
Fraxinus flribunda
Gaultheria fragrantissima
Hedyotis scandens
Hedyotis scandens
Indigolera pulchella
Lyonia ovalifolia
Mangifera indica
Osyris wightiana
Pegia nitida
Pyrus pashia
Rhus javanica
Ribes takare
Rosa burnonii
Rubus ellipticus
Sapium insigne
Schima wallichii
Seteria genniculata
Shorea robusta
Smilax aspera
Terminalia alata
Toona cialita
Zanthoxylum armatum
Local Name
Churi
Utis
Simal
Arile kanda
Guaili
Katus
Bhogate
Kyamuna
Sisau
Mawa
Pangra
Lakure
Dhasingare
Dhudhe lahara
Bokrelahara
Phusareghans
Aingire
Anmp
Nundhiki
Chutilahara
Mayal
Bhakmilo
Dhursurlo
Bhainsi kanda
Ainselu
Khirro
Chilaoone
Kagune jhar
Sal
Kukurdiano
Saj
Tooni
Timur
F
20
80
60
40
20
80
60
40
20
20
80
60
40
20
80
60
40
20
20
80
60
40
20
80
60
40
20
20
80
60
40
20
80
RF
1.28
5.13
3.85
2.56
1.28
5.13
3.85
2.56
1.28
1.28
5.13
3.85
2.56
1.28
5.13
3.85
2.56
1.28
1.28
5.13
3.85
2.56
1.28
5.13
3.85
2.56
1.28
1.28
5.13
3.85
2.56
1.28
5.13
RD1
0.26
17.57
1.03
0.52
1.55
13.44
1.29
1.29
2.07
8.79
0.26
0.26
1.55
1.03
1.55
0.52
13.95
0.26
0.26
0.26
0.52
0.52
10.34
1.03
0.26
1.03
5.94
2.07
1.55
1.81
2.33
0.78
4.13
RD2
5.11
7.51
0.20
0.10
0.31
2.65
0.26
0.26
0.41
1.47
0.05
0.05
0.10
0.20
0.31
0.10
2.76
0.05
0.05
0.05
0.10
0.10
2.04
0.20
0.05
0.20
1.17
0.41
0.31
0.36
0.46
0.15
0.82
IVI
6.65
30.21
5.08
3.18
3.14
21.22
5.40
4.11
3.76
11.54
5.44
4.16
4.21
2.51
6.99
4.47
19.27
1.59
1.59
5.44
4.47
3.18
13.66
6.36
4.16
3.79
8.39
3.76
6.99
6.02
5.35
2.21
10.08
Remarks

High



High



Medium






High
Low
Low



Medium









Medium

F = frequency, RF = relative frequency, RD1 = relative density, RD2=relative dominance, IVI = importance value index



institution of community forest management, human
disturbance continues in various forms, including
development activities, grazing, tree felling, fuel wood
collection, and encroachment on marginal land. The
presence of mature trees (>70 cm Gbh) is the result of
prolonged forest management, while the small poles
and stumps in non CF areas signs of early succession
and uncontrolled disturbance before project since
2001.
At the time of study, there were 15 (53.57%) trees/ha
in Haryali CF, 7 mature trees (35.71%) in Golma raja
Golma Rani CF as compared to 2 mature tree
(7.14)/ha in powerhouse area and rest 3.52%
immature trees were found in powerhouse and
penstock area. The reduced diversity of vegetation
can be attributed to the project impact noted above,
which was particularly severe due to the loss and
disturbance of project intervention and not
implementation of mitigation measures mentioned in
EIA report. The EIA report had already mentioned
plantation of 0.6ha cleared forest lands and
compensatory plantation
Disturbance has been considered an important factor
structuring forest communities (Foster 1980) and
different levels and types of disturbance have a
differential impact on forest communities (Halpern and
Spies 1995). High human and other biotic pressures
with development activities are detrimental to the
vegetation structure of forests.
A total of 19 plant families were reported in sample
plots of Haryali CF, 14 in Audit C and 11 above
penstock in Golma Raja Golma Rani CF, 7 in Penstock
area and 5 in powerhouse area respectively. Among
them, three families (Rosaceae, Leguminosae and
Anacardiaceae) were identified as more abundant.
Leguminosae was the most diversified family with 4
in disturbed slopes.

Page 8

090 Int. Res. J. Plant Sci.






Figure 4. Dominance diversity curve for the tree species given in Table 3



Table 4. Diversity indices of sampling plots

Total Number of trees and Shrubs
Simpson Index (Evenness):
Dominance Index (D = 1 - Simpson):
387
0.09336
0.9066
Total Number of Species:
Whittaker's Index S/alpha):
Alternate Whittaker's Index (S/alpha-
1):

Number of Common Species:
Sørensen's similarity index:
Sørensen's similarity index (%):
33
1
0
Simpsons Reciprocal Index =1/D
Berger-Parker Dominance Index:
Inverted Berger-Parker Dominance Index:
Shannon-Wiener Index:
Hills diversity number (H)
No (Species richness)
N1
N2
Jaccards coefficient (J)
10.71
0.1757
5.691
2.732

33
1
100%
19
17.92
1.071
0.37



individuals, 3 species and 3 genera, followed by
Rosaceae, with three individuals, Anacardiaceae two
species and two genera. Alnus nepalensis in Golma
Raja Golma Rani CF above Penstock contributed the
maximum sapling density (340 trees /ha), or about
53.24% of the total stand Density and Lyonia ovalifolia
(270 tree /ha), or about 42.28% of the total stand. The
maximum density in that area is due to protection of
naturally regenerated species through non access for
livestock and local people.
Stand density differed slightly among study sites,
although there was a broad similarity in major species
composition. Density is influenced by various factors,
including elevation, soil type, dominant and associated
species and human activities (cf. Shrestha et al. 1998).
Climatic factors, environmental stability, land use and
area and habitat heterogeneity are the factors often
discussed as determinants of variability in species
richness (Spies and Turner 1999).
In three sampling sites of these study areas, the
values for total basal area and density were higher
than the values (15-60 m2/ha and 320-2080 trees /ha)
reported by Bhandari et al. (1997) in temperate forests
of the Garhwal Himalaya. As vegetation matures, total
stand density tends to decrease and the stand
increases in height, basal area and volume. Density
and dispersion are quite sensitive to size and intensity
of disturbance. The remarkable differences in stand
density between the managed and disturbed forest
areas were due to development intervention and its
proper management history.
The total basal area also differed significantly i.e.
12.24m2 in quadrate 1, 3.16m2 in quadrate 2 and 2.27
m2 in plot 4, respectively. The higher total basal area in
plot 1 was the result of the high proportion of tree

Page 9

Khan et al. 091



Table 5. Percentage Diversity Indices of sampling plots

SN Scientific Name Numbers Percentage (ni(ni - 1))/(N(N - 1))
(ni)ln(ni/N)
-0.0154
-0.3055
-0.04726
-0.02721
-0.0646
-0.2697
-0.05619
-0.05619
-0.08019
-0.2137
-0.0154
-0.0154
-0.0646
-0.04726
-0.0646
-0.02721
-0.2748
-0.0154
-0.0154
-0.0154
-0.02721
-0.02721
-0.2346
-0.04726
-0.0154
-0.04726
-0.1678
-0.08019
-0.0646
-0.07258
-0.08747
-0.03767
-0.1317
-2.73236
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
Total
Aesandra butyracea
Alnus nepalensis
Bombax ceiba (L.)
Caesalpinia decapitala
Callicarpa macrophylla
Castanopsis tribuloides
Citrus maxima
Cleistocalyx operculata
Dalbergia sissoo
Engelhardia spicata
Entada phaseolodies
Fraxinus flribunda
Gaultheria fragrantissima
Hedyotis scandens
Hedyotis scandens
Indigolera pulchella
Lyonia ovalifolia
Mangifera indica
Osyris wightiana
Pegia nitida
Pyrus pashia
Rhus javanica
Ribes takare
Rosa burnonii
Rubus ellipticus
Sapium insigne
Schima wallichii
Seteria genniculata
Shorea robusta
Smilax aspera
Terminalia alata
Toona cialita
Zanthoxylum armatum
1
68
4
2
6
52
5
5
8
34
1
1
6
4
6
2
54
1
1
1
2
2
40
4
1
4
23
8
6
7
9
3
16
387
0.26%
17.57%
1.03%
0.52%
1.55%
13.44%
1.29%
1.29%
2.07%
8.79%
0.26%
0.26%
1.55%
1.03%
1.55%
0.52%
13.95%
0.26%
0.26%
0.26%
0.52%
0.52%
10.34%
1.03%
0.26%
1.03%
5.94%
2.07%
1.55%
1.81%
2.33%
0.78%
4.13%
100.00%
0
0.0305
8.03E-05
1.34E-05
0.0002008
0.01775
0.0001339
0.0001339
0.0003749
0.007511
0
0
0.0002008
8.03E-05
0.0002008
1.34E-05
0.01916
0
0
0
1.34E-05
1.34E-05
0.01044
8.03E-05
0
8.03E-05
0.003387
0.0003749
0.0002008
0.0002812
0.000482
4.02E-05
0.001607
0.09335405



circumference greater than 70 cm (Figure 2).
Trees with larger diameter have wider canopy cover
and as canopy becomes close plant competition
intensifies and slow growing trees become stunt and
die. The wide range in basal area in plot 1 shows its
heterogeneity. The presence of a large number of
trees in the 10-30 cm diameter class indicates that the
study area is in mid-level succession. However, there
were few trees in the small size classes (<10 cm): only
in plot 3 and plot 4. The paucity of small trees indicates
that the forest is not sustaining itself. This may be due
to the recurrent human disturbance. The extent of
disturbance can be attributed to easy access, grazing,
inefficient management of planted species, and lack of
alternative sources of forest products.
Local people involved in community forestry
programmes, on the other hand, generally protect their
forests and access to government managed forests out
of self-interest (Shrestha and Paudel 1996, Kunwar
2002). Strengthening local control, strongly
implementation of EIA mitigation measures in project
influence area and policy oversight is urgently needed
to assure long-term sustainability of the project and
maintaining integrity of the local environment (Bhatt R.
et al. 2009).
The top niches were occupied by Alnus nepalensis,
Castanopsis tribuloides, Engelhardia spicata in three
plots in all sites; the remaining species shared the
intermediate and lower niches more or less equally.
However, the powerhouse area was occupied planted
species with low numbers and naturally regenerated
Alnus nepalensis was degrading. The gentle slope of
D-D curve (Figure 3) observed in indicates steady
growth of trees in Haryali and Golma Raja Golma Rani
CF, while sharp depression of the curve representing
the small size classes trees in powerhouse and
penstock area is the result of human disturbance or
project intervention. The distribution pattern of tree
species was similar, with the notable exceptions of
Schima wallichii in plot 1 and Terminalia alata in site 2.

Page 10

092 Int. Res. J. Plant Sci.



Table 6. Vegetation characteristics of various forest types

Forest type Location Study
/Plot size (m2)
area (ha) Girth
size
(cm)
>30
T. stand density
(trees ha_1)
T. basal
area
Source

Shorea
forests
Castanopsis
hystrix forests
Shorea-
Castanopsis
forests
Castanopsis
hystrix forests
Riverine forests
robusta
RBNP,
Nepal
MBNP,
Nepal
MBNP,
Nepal
2.81 / (25x25) 333-385 32-35 Giri et al. (1999)
0.60 / (10x10) > 30 1921-3075 23-36 (Shrestha
2002
Chaudhary
Kunwar (2002)
et al.,
3.84 / (20x20)
≥ 10 1425 59 and
MBNP,
Nepal
KTWR,
Nepal
Kavre, Nepal
0.60 / (10x10)
≥ 30 1921-3075 23-36 Shrestha
(2002)
Karki et al. (2001)

Shrestha
(1998)
Khera et al.(2001)
et al.
1.84 / (20x20)
≥ 30 472-652 20-31
Temperate forests 0.37 / (10 m radius) - 5-132 8-19 et al.
Himalayan forests Nainital,
India
Southern
India
Southern
India
Garhwal,
India
Eastern
ghat, India
Jau
Amazonia
0.10 / (10x10)
≥ 30 620 16.8
Dry
forests
Dry
forests
Himalayan forests
evergreen 0.50 / (50x20)
≥ 20 280-1130 11-36 Visalakshi (1995)
evergreen 2.00 / (100x50)
≥ 10 453-819 11-20 Parthasarathy
Sethi (2001)
Pande (2001)
and
0.20 / (10x10)
≥ 10 792-1111 56-126
Semi
forests
Upland forests
evergreen 4.00 / (10x10)
≥≥30 367-667 26-42 Kadavul
Parthasarathy 1999)
Ferreira and Prance
(1998)
and
NP, 4.00 / (40x10)
≥≥30 160-178 32-40



Such pattern of distribution is a general characteristic
of nature (Odum 1971)
Under severely disturbed conditions, the age class
distribution of colonizers may be narrow, while
individuals of diverse ages are found where
disturbance is less severe (Figure 2). A total of seven
size-classes of tree species with an interval of 10 cm
Gbh were recognized for each forest site; such a large
number of size-classes are the result of better
protection due to community forest management. The
proportion of different age-classes of plant species
across a landscape and over time is one of the
fundamental characteristics of the vegetation mosaic
(Spies and Turner 1999). The reverse ‘J’ shaped size-
class distribution curve was obtained which is typical of
all types of forests (Ferreira and Merona 1997).
If one compares the Shannon diversity values
observed in the present study with the values reported
(between 1.16-3.4) for temperate forests by Saxena
and Singh (1982), the present study falls within the
earlier reported range. Biodiversity was relatively low in
project intervened area. The impact of human activities
such as firewood/fodder collection, tree felling and
cattle grazing as well as project activities browsing
accounts for the reduced diversity of vegetation in
direct impact zone of the project. The representation of
species number in natural forest areas in plot 1-3 was
found high species richness and decreasing number in
project disturbed area in plot 4 and 5. The hill diversity
number and Jaccards coefficient (J) was also found in
decreasing pattern in disturbed area. The similarity
index of the studied sites reveals a remarkable degree
of overlap in vegetation composition and structure.


CONCLUSION

Differences in number of individual trees, species,
families, total basal area, and vegetation composition
may be due to differences in local environmental
variables (disturbance gradients and vegetation
characteristics). The dominance of Schima wallichii,
Terminalia alata, Alnus nepalensis, Lyonia ovalifolia,
Castanopsis tribuloides, with their major contribution to
total basal area, frequency, stand density and IVI,
indicates that these are frequent in the studied forests.
The contribution of seven species to total species
diversity and of three species to dominant species list
indicated that the study area vegetation is Schima
wallichii dominant in plot 1, Terminalia alata in plot 2,
Engelhardia spicata and Castanopsis tribuloides in plot
1 and 2, and Alnus Nepalensis in plot 3, 4 and 5
respectively. Although the forest existed in several
girth classes, there was a reduced number of small

Page 11

tree individuals (<10 cm) in plot 3,4 and 5 which may
be attributed to recurrent disturbances (marginal land
encroachment, grazing and firewood collection); this
dearth of immature individuals indicates impaired
sustainability of the surveyed
management for CF and protection of regenerated
species and additional plantation in disturbed areas
surrounding in the project as per recommendation of
EIA and local control over the forests is therefore
urgently needed. The present study conclude that the
project impact on forests of project influence area
cannot recover the natural condition of the local
environment but the effective implementation of EIA
mitigation measures could reduce the impacts. To
meet the natural condition in project impact area,
intensive control on human disturbance in forest and
afforested areas as well as protection of natural
regeneration of species may preserve integrity of local
ecosystem.


ACKNOWLEDGEMENT

The authors acknowledge express their gratitude and
thanks to the support and encouragement extended
from School of Science. Kathmandu University, Nepal.
The help and cooperation of Indrawati III Hydropower
Project is acknowledged. The financial support
extended by the Nepal Academy of Science and
Technology to the first author for Ph.D. fellowship is
gratefully acknowledged.


REFERENCES

Bhandari BS, JP Mehta, BP Nautiyal, SC Tiwari (1997). Structure of
a chir pine (Pinus roxburghii Sarg.) community along in altitudinal
gradient in Garwal Himalaya. Int. J. Ecol. Environ. Sci. 1:67-
74.
Bhatt R, Khanal S ( 2009). Environmental Impact Assessment
System in Nepal - An overview of Policy, Legal Instruments and
Process. Kathmandu University Journal of Science, Engineering
and Techenology. VOl. 5, No. II: 160-170p.
Braun-Blanquet J (1932). Plant Sociology: The study of plant
communities: New York, McGraw-Hill, 439 p.
Clements FE (1920). Plant Succession: An Analysis of the
Development of Vegetation: Washington, D.C., Carnegie Institute,
388 p.; Publication No. 290.
Dobromez F J (1974). Divisions Phytogeographiques du Nepal et de
l’Himalaya (The Major Phytogeographical Regions of Nepal and
the Himalayas). Bull. Soc. Bot. France,119 (1/2): 111-120.
Ferreira, L.V. and Rankin-de Merona, J.M. 1998. Floristic composition
and structure of a one-hectare forest in central Amazonia . Pp.
649-662 in Dallmeier, F. and Comiskey, J.A. (eds). Forest
biodiversity in North, Central and South America, and the
Caribbean . Research and Monitoring. MAB Series Vol. 21.
UNESCO, Paris.
Foster RB (1980). Heterogeneity and disturbance in tropical
vegetation. In: Soule’ ME and BA Wilox (eds), Conservation
biology: An evolutionary ecological perspective. Sunderland (MS):
Sinauer Associates. p 75-92
FW P (1948). The commonness and rarity of species. Ecology 29:
254-83.
GoN. (1996). Topographic maps.(1:50.000). Nepal Survey
forests. Better
Khan et al. 093



Department in Cooperation with the Government of Finland.
GoN, MoLJPA (1997). Environmental Protection Act 1997 and
Environmental Protection Regulation 1997. Ministry of Law,
Justice, and Parliamentary Affairs). Law Books Management
Board. Kathmandu. Nepal.
GoN/Earth Science (1984) . Department and Kenning Earth Science
Ltd. Canada: Land Resource Mapping Project.
GoN, MOE, NHC (2002). Environmental Impact Assessment of
Indrawati Hydroelectric Project. National Hydropower Company
Ltd. Kathmandu. Nepal.
Halpern CB, Spies TA (1995). Plant species diversity in natural and
managed forests of the Pacific Northwest. Ecol. Appl 5: 913-34.
Hill MO (1973). Diversity and evenness: A unifying notation and its
consequences. Ecology 54: 427-32
Jaccard, P. (1912). The distribution of flora in alpine zone. New Phytol
11: 37-50. New Phytol 11: 37-50.
Jalas J (1955). Hemerobe and hemerochore Pflanzenarten - ein
terminologischer Reformversuch. Acta Soc. Fauna Flora Fenn.
72(11), 1-15.
Kunwar RM ( 2002). Participation and benefits to local people in
community forestry: A case from Makawanpur district, Nepal
[thesis]. Bhopal (India): Indian Institute of Forest Management. 93
p
Kowarik I (1990). Some responses of flora and vegetation to
urbanization in Central Europe. In: H. Sukopp, S. Hejný and I.
Kowarik (Editors), Urban Ecology: Plants and Plant Communities
in Urban Environments. SPB Academic Publishing bv, The Hague,
The Netherlands, pp. 45-74.
Kowarik I (1988). Zum menschlichen Einfluss auf Flora und
Vegetation – Theoretische
Quantifizierungsansatz am
Landschaftsentwicklung und Umweltforschung, Schriftenreihe des
Fachbereichs Landschaftsentwicklung der TU Berlin 56, 1-280.
Mueller-Dombois D, Ellenberg H ( 1974). Aims and methods of
vegetation ecology. New York: John Wiley and Sons. 547 p
Odum EP (1971). Fundamentals of ecology, 3rd ed. Philadelphia:
Saunders. 574 p
Parthasarathy N and P Sethi. 2001. Tree diversity in a dry evergreen
forest. Trop Ecol 42(1): 20-9.
Reif A (2000). Das naturschutzfachliche Kriterium der Naturnaehe und
seine Bedeutung fuer die Waldwirtschaft. Z. Ökol. Nat.schutz 8:
239-250.
Shannon CE, Weiner (1963). The mathematical theory of
communication. Urbana (USA): University of Illinois Press. 117 p.
Sukopp H (1969). Der Einfluss des Menschen auf die Vegetation.
Vegetatio 17, 360-371.
Saxena AK, Singh JS (1982). A phyto-sociological analysis of forest
communities of a part of Kumaun Himalaya. Vegetation 50: 3-22
Saxena AK, Singh JS (1984). Tree population structure of certain
Himalayan Forest association and implications concerning their
future composition. Vegetation 58: 61-9
Science GE (1984). Land Utilization, Land Capability, Land System
Map (1:50,000). GoN, Topographical Survey
Shrestha S, PK Jha and KK Shrestha 1998. Vegetation of degraded,
regenerating and natural forests in Riyale, Kavre, Nepal. Pak J.
Pl. Sci. 4(1): 13-28
Shrestha RK, Paudel KC (1996). Oak forest under threat: an urgent
concern for the mountain environment. In: Jha PK, GPS Ghimire,
and SB
Shrestha K (1998). Dictionary of Nepalese Plant Names. Mandala
Book Point. Kathmandu Simpson EM. 1949. Measurement of
diversity. Nature 163: 688
Spies TA, Turner MG (1999). Dynamics forest mosaics. In: Hunter
ML Jr. (ed.). Maintaining biodiversity in forest ecosystems.
Cambridge: Cambridge University Press. p 95-160
Stainton (1972). Forest of Nepal. Jhon Murray: London, 181 p.
Verma RK, Singh D(2001). Analysis of biodiversity and improvement
in soil quality under plantations on degraded land. For 24(1): 21-8:
IndJ.
Visalakshi N (1995). Vegetation analysis of two tropical dry evergreen
forests in Southern India. Trop Ecol 36(1): 117-27.
Whittaker R H (1953). A consideration of climax theory: the climax as
Konzepte
von
und ein
Beispiel Berlin (West).

Page 12

094 Int. Res. J. Plant Sci.



a population and pattern. Ecol. Monogr. 23: 41-78.
Whittaker RH(1976). Evolution and measurement of species diversity.










Taxon 21: 231-51.