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International Journal of Agriculture and Crop Sciences. Available online at www.ijagcs.com 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). 525 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). 526 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 527 Intl J Agri Crop Sci. Vol., 7 (9), 524-531, 2014 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 528 Intl J Agri Crop Sci. Vol., 7 (9), 524-531, 2014 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. 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