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International Journal of Agriculture and Crop Sciences.
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IJACS/2014/7-9/524-531
ISSN 2227-670X ©2014 IJACS Journal
The effective factors on diversity of natural
regeneration and herbaceous vegetation in forest
corral area in northern forests of Iran
MohsenJavanmiri Pour*1,Mohammad Reza Marvi Mohadjer2, Vahid Etemad3
1. Natural Resources Faculty, University of Tehran, Karaj, Iran
2. Natural Resources Faculty, University of Tehran, Karaj, Iran
3. Natural Resources Faculty, University of Tehran, Karaj, Iran
*
Corresponding author email: [email protected]
ABSTRACT: In this study the effective factors such as physiographic factors and cattle grazing on
diversity of natural regeneration and herbaceous vegetation was investigated. In order to study grazing
effectson diversity of forest regeneration and herbaceous cover was used four routes based on suitable
slope for animal crossing as line transect to custom unit boundary. Then 80 plots was established in
regeneration groups on transect. In order to study physiographic factors around the corral four transect
was used in different geographical aspectswhich include altitude, slope and domain. In this study
Simpson, Shannon-Wiener and Brillouin indiceswere used for species diversity and Camargo, Simpson,
Modified Nee and Smith & Wilson were used for species evenness in Ecological methodology version 6.
Also significant results showed increases diversity of tree species by increasing distance from corral in
500 mdistance classes and evenness indices show increases evenness of species by increasing distance
from corral in 500 mdistance classes. Results of ANOVAindicate different effects of height from sea level,
direction and slope on the richnessevenness and species diversity. The result showed was significant the
effect of height from sea level on diversity while not significant on richness and evenness. Also the
results show was significant effect of domain direction on diversity and richness while not significant on
evenness.
Key words: diversity, evenness and richness,grazing, physiographic factors, regeneration groups
INTRODUCTION
Natural ecosystems have characteristics such as resilience, biodiversity andcomplexity that should be
considered these as cases management and interference in forest and maximized them to ensure the sustainability
of ecosystems (Le´veˆque andMoundolou, 2001, Plieninger, 2005).
Biodiversity that include diversity, variety, population structure, spatial pattern and distribution plants can
be used to compare the ecological condition of forest ecosystems and it guarantee of flexibility and
adaptationcapacity offorestecosystems (Le´veˆque andMoundolou, 2001, Alijanpour et al., 2009).
Species diversity index is one the important biodiversity indices that is usedtoo much in the habitats assessment
and depends on stability of the environment (Giliba et al., 2011).
Because of this stability variesin different communitiesandecosystemswill affected bychanges
environmental condition.So is very important performance and human interfering in natural ecosystems (Hooper et
al., 2005). In fact, when the system is stable, species evolve during the time and also does not have high
fluctuation individuals which constitute its population. High species diversity confirms the establishment of many
species in site due to favorable environmental conditions (Eshaghi Rad and BanjShafiei, 2009). Toconserve forest
complexity and biodiversity, silviculture and forest management should change the paradigm and consider forest
ecosystems as a complex biological system characterized by inherent unpredictability of their evolution in a
continuously changing environment (Ciancio and Nocentini, 2011, Nocentini, 2011).
Human factors deforestation includes grazing, fire, land-use, mining operation, wood smuggling and
release of waste in the forest (Harrington, 1979). Cattle grazing (ungrazed or intensely grazed once), plant species
origin (native or exotic), and species richness (mixture or monoculture) treatments were fully crossed and randomly
Intl J Agri Crop Sci. Vol., 7 (9), 524-531, 2014
assigned to plots of grassland plants (Hickman, 2004, Isbell and Wilsey, 2010). Increasing species richness from
one to four species increased aboveground production by 42%, and light interception to 44%, in both ungrazed and
intensely grazed (Coblentz and Riitters, 2004). The forest considered as viable community, if this plant community
is threatened only by natural factors have the ability to renew their community unless human accelerate the natural
destruction (Darabant et al., 2007). Browsing caused the formation of an extremely low diversity herbaceous
understory dominated by a single fern species, caused extirpation of shrubs, and drove forbes to extremely low
abundance ( Royo De Sedas, 2005, Goetsch et al., 2011).
Coblentz and Riitters (2004) in the south-western USA by using topographic analysis evaluate the role
played by topography in the distribution of regional-scale biodiversity.
Alijanpour et al., (2009) results showed that there was significant difference at one percent level between
mean species richness index, evenness index, Shannon – Wiener species diversity and Simpson's diversity index
in both protected and unprotected areas.
The most of species depend on increase of structural diversity at different space and time scales (Isbell
and Wilsey, 2010).
Results of the study of the pine forest (Pinussylvestris L.) showed reduction in number of livestock has
significant effects on regeneration, diversity, changes in species and forest succession during the 100 years in the
Netherlands (Jorritsma et al., 1999, Török et al., 2008).
Studies show that human disturbances have been caused increasing dominance of pine and reduction in
under story richness in Mexico (Marcial et al., 2001).
2
In a study reduction in herbivores biomass amount 500 kg/km was determined that it was a significant
increase in total number of seedlings in vegetative types (Kuiters and Slim, 2002).
In this study the effective factors such as physiographic factors and livestock grazing on diversity of natural
regeneration and herbaceous vegetation in forest corral area was investigated.
MATERIAL AND METHODS
Study area
The Caspian region is located in south of the Caspian Sea. The study area is located in theNamkhaneh
district, in the Kheyroud Educational and Experimental Forest which belongs to the University of Tehran (ca.
8000 ha) 7 km southeast of the Nowshahr city in Mazandaran province, in northern Iran (36°30′30″ to 36°32′30″N
and 51°40′00″ to 51°41′30″E). Common forest soils are deep brown, with clay to clay loam textures derived from
calcareous and dolomite rock and the climate is humid with cold winter (Habibi, 1984). Mean annual precipitation at
the nearest meteorological station (Nowshahr) is 1380 mm without any dry season. The mean temperature is
24.6 °C during the hottest month and 7.5 °C during coldest month. Relative humidity varies between 75% and 85%
(Salehi et al., 2005). In Caspian forests, trees are harvested by using single-selection or group-selection system
based on forest management planning. The management objectives are conservation, rehabilitation, development
and exploitation according to sustainable forest management (SFM). The Kheyroud forest is uneven-aged
(generally middle-aged to mature forest) with mixed broadleaf trees. Oriental beech (FagusorientalisLipsky) and
hornbeam (Carpinusbetulus L.) are the dominant species.
METHOD OF COLLECTING DATA
In order to assess the effects of cattle grazing on biodiversity of regeneration Souch corral in Namkhaneh
district was considered as grazed region. 1/10000 topographic maps have been used for this study. After field visits
were identified Souch corral in study area. Then custom unit from Souch corral was determined by using custom
unit map. Then was moved from corral on four routes based on suitable slope for cattle movement to custom unit
2
boundary. Then 2.5×2 (5m ) plots was established in regeneration groups along transect.
survey of cattle grazing and physiographic effects
For study grazing effects on diversity of forest regeneration and herbaceous cover with physiographic
factors around the Souch corral four transects was selected in geographical aspectwhich includes altitude, slope
and domain. Spatial settlement of these transects is different from cattle corridors.
Height above sea level was determined by using Altimeter, percentage slope by Suunto and direction
geographical by registering exact azimuthfrom top to bottom slope.
In each plot seedling species, dominant seedling in regeneration group, herbaceous species, dominant
herbage and their cover percentage was determined (Walker et al., 2013).
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Intl J Agri Crop Sci. Vol., 7 (9), 524-531, 2014
In this study 45 sample were established in 0-500, 500-1000, 1000-1500 and 1500m horizontal distances
and 35 sample plots were established in geographical aspects. Altitude range was divided in 4 classes (700-750,
750-800, 800-850 and 850), 3 slopes classes (0-30%, 30-60% and 60%) anddirection of domain include north,
south, east and west.
METHOD OF BIODIVERSITY DATA ANALYSIS
Species richness indicates the frequency of various species and is calculated by counting the
number of speciesin specific site. In this study Simpson, Shannon-Wiener and Brillouin index were used for species
diversity and Camargo, Simpson, Modified Nee and Smith & Wilson were used for species evenness in Ecological
methodology software (Kerbs, 2013).
Also in order to calculate significance was used in ANOVA test in Spss 16.0. software.
RESULTS
The number and types of species
Totally 212 plant species were identified that belong to 161 genus and 78 familiesthat species of ferns, 42
single cotyledon species and 146 dicotyledonous species are among them (Table 1).
The results show that Phanerophytes form the highest percentage (48%) of life forms in region then form of
geophytes (18.7%), Hemicryptophytes (18.1%), Therophytes (7.2%) Chamephytes (1.5%) and other life form (.5%)
respectively.
Changes in the types of tree species
Changes in the dominant species show that the number of Carpinusbetulusand A. cappadocicum species
reduce andthe frequency of F.orientalis will increase by increasing distance from corrals. Other species include
Crataegussp, P. persica, T. begonifolia, D. lotus, Mespilusgermanica also show a decreasing trend. F.orientalis
companion speciesUlmusglabra, F.exlesior, Q. castaneifolia, A.velotinum have increasing trend (Fig 2).
Indices of species richness
Results of Species diversity show increases diversity of tree species by increasing distance from corral in 500
mdistance classes by using Brillouin, Shannon-Wiener and Simpson indices (Fig 3).
Indices of evenness
Results of evenness indices show increases evenness of species by increasing distance from corral in 500
mdistance classes by using Camargo, Simpson, Smith & Wilson and modified Nee indicators (Fig 4).
Herbaceous change in horizontal distance class
Table 2 shows thatthe dominant herbage species includeOxalisacetosella, Rubusfruticsus,
SambucusnigraandPteridiumaquilinum in 0-500 m distance. Euphorbia amygdaloides, R.fruticsus,
OplismenusundulatifoliusandGraminoidessp are dominant herbage species in 500-1000 m distance.
O.undulatifolius and Graminoidesspare dominant herbage species in 1000-1500 m distance.
Hypericumandrosaemum, Graminoidesspand Viola sylvestrisare dominant herbage species in 1500 m distance.
Tree species change in horizontal distance class
Table 3 shows that the dominant seedlings species include D.lotus, Crataegussp,C.betulus, M.germanica,
A.cappadocicum and P.persicaarein 0-500 m horizontal distance.Pronusdivaricata, A.cappadocicum, F.orientalis,
T.begonifoliaand C.betulus are dominant tree species in 500-1000 m horizontal distance.
A.velotinum, F.orientalis and Q.castaneifolia are dominant tree species in 1000-1500 m horizontal
distance. F.orientalis, A.velotinum and Fraxinus excelsior are dominant tree species in 1500 m horizontal
distance.
SIGNIFICANT RESULTS
Results of ANOVAindicate different effects of height from sea level, direction and slope on the
richnessevenness and species diversity. The results show was significant the effect of height from sea level on
diversity (P=0.030)while not significant on richness (P<0.076) and evenness (P=0.051).
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Intl J Agri Crop Sci. Vol., 7 (9), 524-531, 2014
Also the results show was significant effect of domain direction on diversity (P=0.000) and richness
(P=0.000) while not significant on evenness (P=0.94). Also results show not significant on diversity (P=0.54),
richness (p=0.43) and evenness (P=0.68).
Table1. Number of families, genus and species in groups of plant
Groups of Plant
Fern
Gymnosperms
Single cotyledon
Dicotyledonous
Total
Family
10
1
11
54
78
Genus
15
1
33
112
161
Species
23
1
42
146
212
Table2. The dominantherbagespecies at 500 m distances from corral
Distance
from corral
0-500
Route 1
Route 2
Route 3
Route 4
P. aquilinum
Euphorbia
amygdaloides
O. undulatifolius
Viola sylvestris
P. aquilinum
Oxalis acetosella -Rubusfruticsos
Sambucusnigra
500-1000
E. amygdaloides-graminoidessp
Oplismenusundulatifolius
1000-1500
1500
O. undulatifolius- graminoidessp
Hypericumandrosaemum
graminoidessp
graminoidessp
R. fruticsos
graminoidessp
graminoidessp
Table1. The dominanttreespecies at 500 m distances from cow-pens
Distance from cowpens
Route 1
Route 2
0-500
D. lotusCrataegussp
D. lotus-C.betulus
500-1000
Pronus divaricate
A.cappadocicum
1000-1500
1500
A.velotinum
F. orientalis
F. orientalis
F. orientalis
Route 3
Route 4
M.germanicaA.cappadocicum
F. orientalisT.begonifolia
Q.castaneifolia
F. orientalis
M.germanica- P.
persica
C.betulus
F. orientalis
A.velotinum
Table4. Results of ANOVA about richness, evenness and species diversity in slope classes, direction and altitude
Source of
variation
Mean square
Height from sea
level
Direction
Slope
Diversity
Richness
Evenness
Diversity
Richness
Evenness
Diversity
Richness
Evenness
1.1
119
.05
1.9
404
0
.165
35
0
Degrees of
freedom
3
3
3
2
2
2
2
2
2
F
P
3
2.4
2.8
9.3
19
.05
.6
.99
.34
.03*
.076 ns
.051 ns
**.000
**.000
.94 ns
.54 ns
.37 ns
.70 ns
**Indicates significance at 1% level, * Significant at 5% level and ns: not significant
Figure2. Location of site study
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number of seedlings
1000
F. orientalis
a.cappadocicum
C. betulus
other species
500
0
500-0
number of seedlings
1000
1000
-500 from
1500
-100 (m)1500<
distances
cowpens
F. orientalis
a.cappadocicum
C. betulus
other species
500
0
500-0
1000-500
1500-100
1500<
distances from cowpens (m)
Figure 2. Changes Types species at 500 m distances from corrals
Simpson
Shanon-Wiener
Brillouin
number of variety
index
3
2.5
2
1.5
1
0.5
0
500-0
1000-500
1500-1000
distance
from cowpen
(m)
1500<
number of evenness index
Figure 3. Changes of variety indices in the 500 m distances from corral
Camargo
Simpson
Modified Nee
Smith & Wilson
0.6
0.4
0.2
0
500-0
1000-500
1500-1000
1500<
distance from cowpen (m)
Figure 4. Change in evenness indices in the 500 m distances from corral
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DISCUSSION
The natural course of the succession to create high, uneven age and mixture forest mostly by dominance
of F.orientalis with A.velotinum, F.excelsior, Q.castaneifolia species in 700-1800 m altitude of the northern forests
of Iran.
This study showed that by increasing distance from the center of the crisis (corrals forest) and in 0-500,
500-1000, 1000-1500 and 1500 m distances the frequency of F.orientalisincreases and its companion species
and decreasesabundance of C.betulus and A.cappadocicum species and other succession pioneer species.
Results obtained in this study are consistent with(McCreary and George, 2005), (Wassie et al., 2008) and
(Vazquez, 2002) results.
So it can be said that damage is caused by livestock grazing in areascloser to the corral forest. Destruction
is devastating natural regeneration of forest species and thus is disturbing forest development. For this reason the
existing species in closer distance to corral forest include succession pioneer species such as C.betulus,
A.cappadocicum,Crataegussp, Mespilusgermanica, Pronusdivaricata. Results obtained in this research was
confirmed by (Jorritsma et al., 1999), (Tzanopolous et al., 2006)and (Kuiters and Slim, 2002) results.
Ranchers thinning the forest because there is not enough forage to feed cattle due to the multiple stories
and lack of light penetration in forest floor. The findings of this research confirm to results of studies (Wassie et al.,
2008), (Darabant et al., 2007) and (Farris and Filigheddu, 2008).
Types of invasive plants and undesirable herbage such as Pteridiumaquilinum,Rubusfruticsus,
Oxalisacetosellaappear by effects of forest thinning and girdling in the forest corral surrounding area.
When forest canopy cover will be opened and light will enter to the forest floor, other groups of herbage plants such
asO.undulatifolius and Euphorbia helioscopiaareexist by the destruction of forests and grazing of livestock. Barnes
et al. 1997 were achieved similar results.
The results of (Nouri et al., 2008) showed that the total number of tree species is 9 and 14 species in
grazed and ungrazed areas respectively. Comparing indices showed that richness indices values in grazed area
are higher than these values in the ungrazed area.
Values of species richness indices indicate increasing diversity and evenness of species with increasing
distance from corraldue to reduced grazing pressure by being away from the corral. This result is consistent with
(Buffum et al., 2008) , (Harrington, 1979) and(Gillespe et al., 1999) results.
In conditions further destruction appear thorny species such as Crataegusspin areas closer to the forest
corral that have nurse role for created regeneration. Confirms the results that have been obtained from this
research (Pollock et al., 2005),(Noack et al., 2010), (Cierjacks and Hensen, 2003), (Matsumoto et al., 1999),
(Vazquez, 2002) and (Farris andFiligheddu, 2008) results. It indicated that the relationship between ecological
groups with slope.
Direction of domain and height are different ecological groups not only for floristic properties and
biodiversity but also from physiographic characteristics.
The results of this study indicate that is significant the effect of height on diversity and richness herbaceous
cover and wooden species. In other word, have significant correlation between height and species richness. There
is increase on the amount of species richness with increased height.
In this study significant has been found relationship between species richness the dominant life forms in the
forestamong the different height classes. The results obtained in this studyare consistent with Esmaillzadeh and
Hosseini (2006) results.
Based on current study has significant effect the direction on richness and species diversity, it is more in
southern and eastern domain than western and northern domain. This effect may be drying in southern and
eastern domain than western and northern domain and therefore lower tree cover and reach more light to forest
floor in this direction.
SohrabiandAkbarinia (2005), Pausas and Austin (2001) research showed thatindicators generalexamine in
relation to physiographic factors shows that altitude has no significant effect on all species diversity indices but was
significant the slope effect on all indicators except Alatalo and Melinari indices. The effect was significant on
bilateral Simpson indices, Shannon and Hill, was not significant on Pielou, Alatalo and Melinari.
Totally, this study showed human disturbance such as grazing can affect like physiographic factors on
appearance, diversity and changing forest species in regeneration groups and herbage cover.
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Intl J Agri Crop Sci. Vol., 7 (9), 524-531, 2014
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