Growth and biomass production of lowland forest plantations in north of Iran

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1 Aville online t Scholrs Reserch Lirry Archives of Applied Science Reserch, 212, 4 (1): ( ISSN X CODEN (USA) AASRC9 Growth nd iomss production of lowlnd forest plnttions in north of Irn Niloufr Hghdoost, Moslem Akrini, Seyed Mohsen Hosseini Deprtment of Forestry, Fculty of Nturl Resources, Trit Modres University, Noor, Mzndrn, Irn ABSTRACT Plnttions my ply n effective role in lncing the CO 2 levels in tmosphere y cpturing nd storing the cron in iomss nd soil. There re few studies in north of Irn whit focusing on cron sequestrtion in forested lnds. Acer velutinum.boiss, Alnus sucordt.l nd Cupressus sempervirens. vr. horizontlis re the most used species in lowlnd plnttions in this region. We quntified survivl rte, growth chrcteristics nd ove- nd elowground iomss fter 18 yers of these species estlishment in Chmestn region of Mzndrn province. Results showed tht C. sempervirens hd the lowest survivl rte nd growth compred to other studied species. Bsed on higher survivl rte nd rpid growth, A. sucordt my e the est option for lowlnd plnttions in this region. Also our results indicted tht iomss production nd cron storge ws significntly higher in A. sucordt nd A. velutinum plnttions compred to C. sempervirens. The rte of iomss cron storge ws clculted round: 23.41, nd (t/h/yr) for A. sucordt, A. velutinum nd C. sempervirens respectively. These results showed tht lowlnd plnttions in this re cn e very effective on reducing the negtive consequences of glol wrming. Keywords: Aoveground iomss, elowground iomss, CO 2 mitigtion, cron storge, glol wrming. INTRODUCTION Lnd use chnges from forestry to other uses, s well s greenhouse gs emissions ssocited with exploittion of fossil fuels hve disrupted the plnet s frgile cron (C) lnce nd cused glol climte chnge [38]. Prolems cused y glol wrming which ssocited with the increse in Greenhouse Gses (GHG) re the most importnt glol environmentl issue in current century [14]. Even in the most optimistic scenrios, climte chnge cn e detrimentl to severl production chins, with strong impct on developing economies which depend lrgely on griculture [11]. Terrestril nd mrine ecosystems re estimted to sor out hlf of the CO 2 emissions from Scholrs Reserch Lirry 595

2 Moslem Akrini et l Arch. Appl. Sci. Res., 212, 4 (1): fossil fuel comustion [33]. In terrestril ecosystems, C which sored vi photosynthesis is stored in the iomss of living vegettion (leves, rnches, trunks nd roots), litter nd soil [25, 37]. Among terrestril ecosystems, forests my help contriute towrd C sequestrtion y cpturing nd storing tmospheric CO 2 where it is not immeditely re-emitted to the tmosphere [14]. Forest lnds re the primry source of terrestril C uptke, storing pproximtely two-thirds of Erth s terrestril C [3]. Such knowledge hs creted incresed interests in mnging forests for more C sequestrtion. There re numerous cron-sed stores tht recognize wide vriety of terrestril C sequestrtion ctivities s potentilly vile mens for reducing tmospheric CO 2 concentrtions [23]. Forest mngement prctices offer unique mens of offsetting greenhouse gs emissions [2]. Among forest mngement options for C sequestrtion, forest plnttions hve een known s cost-effective nd environmentlly eneficil strtegy for C sequestrtion [23, 14]. Therefore, forest plnttions hve een estlished ll over the world s C stocks [4, 13, 31, 35] to slow down the increse of tmospheric CO 2 concentrtions. A potentil expnsion is possile of 345 million h s trees re plnted in distured forest, pstures or ndoned griculture res [4]. Chnges in silviculturl mngement cn lter C stocking nd enle stored C vlution. In the cse of plnttions, increses in stored C re rought out y regimes tht enhnce long-lived wood product volume. In the cse of existing forests, C sink enhncing is relted to lower deforesttion rtes [11]. Estlishment of lrge-scle short-rottion woody crop plnttions hs een dvocted s n effective method for sequestering CO 2 nd mitigting incresed tmospheric CO 2 levels [34], through incresing long-term C storge in woody iomss [33] nd in the soil [1, 36], nd y providing n lterntive source of iomss for ioenergy [2, 36]. So estimting the production nd iomss C storge of plnttion stnds cn ply n importnt role in mngement pproches for reducing CO 2 levels in tmosphere. Forest production cn e evluted in terms of resource supplies, rtes of use, nd growth [35]. Estimtes of C pools in the vegettion component of forest ecosystems cn e otined y using llometric functions [22, 25]. Such functions llow the estimtion of plnt iomss from vriles tht re esily nd non-destructively mesured, such s plnt height nd trunk dimeter t rest height [25]. In north of Irn, Cspin forests hve een under continuous degrdtion over the lst few decdes nd there is n urgent need to mintin the functions of this unique forest ecosystem [12]. Therefore, different forms of mngement pproches re plnned for implementtion, such s documenting the forest disturnce nd mngement of the remining nturl forest ecosystems in this region [27]. Also forest plnttions were introduced to supply fuel-wood, chrcol, fodder, sticks nd uilding mterils. They were lso plnted to restore degrded lnds, to control soil erosion or to serve s uffer zones round rods nd res of nturl forests [12]. There were mny plnttions with endemic nd exotic species in north of Irn. But, unfortuntely, there is little pulished informtion on tree growth nd iomss in this region. Also results of such reserches re not consistent nd generliztions re not possile nd most of these reserches re not pulished in English lnguge. The ims of this study were to compre growth, iomss production nd iomss C storge of three prevlent species plnttions: (I) Acer velutinum.boiss, (II) Alnus sucordt.l nd (III) Cupressus sempervirens. vr. horizontlis. As mounts of C storge nd iomss ccumultion for studied species re unknown in this re. Also we introduced the most suitle species in terms of mximum iomss C storge. Scholrs Reserch Lirry 596

3 Moslem Akrini et l Arch. Appl. Sci. Res., Res. 212, 4 (1): MATERIALS AND METHODS 2.1. Study re This study ws conducted in Chmestn region t Noor County in Mzndrn province, in the north of Irn. Study sites locted t district 12 of wtershed 51 of northern forests of Irn (36o 29' N, 52o 7' E) with n ltitude of 9 m ove se level nd low slope (<5%) (Fig1). Annul rinfll verges 83 mm, with wetter months occurring etween Septemer nd Ferury, nd dry seson from April to August. Monthly Mo rinfll usully occurs <4 4 mm for 4 months. Averge o o dily tempertures rnges from 11.7 C in Ferury to 29.5 C in August. The soils hve the textures of lom nd cly lom with n cidic ph in top lyers nd in deep lyers soil textures were cly nd silt cly nd soil ph ws less cidic. 18 yers go plnttions hve een estlished (with 2m 2m m spces) in this re with three species including: A. sucordt, A. velutinum nd C. sempervirens [1]. These species re the most used in lowlnd plnttion progrms in north of Irn. We selected three sites ech with n re of 1 h to compre growth nd iomss production. NOOR Fig 1-- Study re loction in northern forests of Irn 2.2. Field mesurements Mesurements esurements were performed to compre growth nd iomss production of ove-mentioned ove plnttions,, in Novemer of 21, 21 fter finishing the growing seson. In ech sites four 1 m 1 m plots were estlished.. Then tree height (H), dimeter t rest height (DBH), dimeter of cnopy or crown in two perpendiculr directions, termed here for convenience length (L) nd width (W), stem height to the se of the crown (Hc) nd percentge of folige cover in the crown or cnopy (Fc) were mesured for ll of the trees in ech plot [26]. Also survivl rte (%) nd sl re were clculted for ech plot Biomss nd cron ccumultions ccumultion First, tree s iomss estimted in two seprte prt of oveground nd elowground, elowground then, the totl iomss ws estimted for ech site. To estimte the oveground tree iomss we used n llometric method suggested y Ponce-Hernndez Ponce et l., [26]: For methodologicl convenience, the clcultions of trees re divided in two sections ccording to tree morphology: (I)) clcultion of iomss for stem (II) ( ) clcultion of iomss for crown. To clcultion of stem iomss, first the sl re estimted y eqution 1: (1) 597 Scholrs Reserch Lirry

4 Moslem Akrini et l Arch. Appl. Sci. Res., 212, 4 (1): Where A is tree sl re, π = , nd r is the rdius of the tree t rest height (.5 DBH). Then the stem volume (V) of ech tree clculted from eqution 2: (2) Where A is tree sl re, H is the totl tree height nd K c is site-dependent constnt in stndrd cuing prctice used in forest inventory. To clcultion of crown volume (V) we used following equtions: (3) For coniferous species (4) For rodlef species Where: π = , D = dimeter of the crown (L+W/2) nd Hc = height from the ground to the se of the crown. The volume of the crown estimted y these equtions is the gross totl volume. In relity, much of this volume is empty spce. The ctul proportion of the volume occupied y rnches nd folige is estimted y stnding eneth the cnopy or crown, eside the trunk, nd otining creful visul pprecition of the cnopy structure. This proportion is then used to discount the ir spce in the crown volume: Solid volume = V proportion of rnches nd folige in crown volume Biomss (stem nd crown) in kilogrms clculted y multiplying y the wood density (WD) corresponding to ech tree species mesured through eqution 5: 1 (5) Totl oveground iomss estimted s: Totl Aoveground Biomss = Stem Biomss + Crown Biomss Becuse of the high cost of root smpling nd mesurement, non-destructive methods (such s llometric equtions) preferred to ssess the elowground iomss. On the other hnd, it is recommended tht in situtions where no empiricl eqution exists, the root volume nd iomss should e estimted s frction of the oveground iomss, s n interim mesure, in order to estimte totl iomss [26]. So following reltionships suggested y Ponce-Hernndez et l., [26] were used to estimte elowground iomss: For coniferous species: Belowground iomss =.25 Aoveground iomss For rodlef species: Belowground iomss =.3 Aoveground iomss These vlues converted to tons per hectre nd then clcultion of C stock s iomss consists of multiplying the totl iomss y conversion fctor tht represents the verge C storge in iomss. It is not prcticlly possile to seprte the different iomss components in order to ccount for vritions in C storge s function of the iomss component. Therefore, we ssumed C to equl 5% of tree s iomss [5, 9, 19, 28, 29]: Scholrs Reserch Lirry 598

5 Moslem Akrini et l Arch. Appl. Sci. Res., 212, 4 (1): C =.5 Biomss (totl) 2.4. Sttisticl nlyses The growth, iomss nd C storge of iomss mong experimentl sites were nlyzed using the rndomized lock design. Normlity of the vriles ws checked y Kolmogorov-Smirnov test nd Levene s test ws used to exmine the equlity of the vrinces. One-wy nlysis of vrince (ANOVA) ws used to compre tree growth, iomss, nd C storge of iomss dt mong experimentl sites. Duncn test were used to seprte the verges of the dependent vriles which were significntly different etween studied sites. RESULTS 3.1. Tree survivl nd growth Mesurements in the experimentl plnttion sites (t the ge of 18 yers) indicted tht A. sucordt hd the higher survivl rte (44%) compred to other studied species. Also C. sempervirens hd the lowest survivl rte (29%) mong plnttion sites (Fig 1). DBH ws significntly higher in A. sucordt in comprison to C. sempervirens ut there were no significnt differences etween A. velutinum nd other plnttion sites (Fig 2). Survivl rte (%) DBH (cm) Crown Dimeter (m) () Totl Hight (m) c () Hc (m) (c) Bsl re (m 2 /h) (d) (e) (f) Fig 2- Comprison of survivl rte (), DBH (), crown dimeter (c), totl height (d), Hc, stem height to the se of the crown (e) nd sl re (f) of three plnttion sites Crown dimeter ws significntly lower in C. sempervirens compred to other plnttions nd Scholrs Reserch Lirry 599

6 Moslem Akrini et l Arch. Appl. Sci. Res., 212, 4 (1): the highest mount of crown dimeter ws oserved in A. velutinum plnttion (Fig 1c). As cn e oserved in the results tht shown in fig 1d, the totl tree heights ws significntly different etween studied plnttion sites nd took the order: A. sucordt > A. velutinum > C. sempervirens. The highest mount of stem height to the se of the crown (Hc) ws oserved in A. sucordt plnttion site (Fig 1e). The stnd sl re, s shown in fig 1f, ws higher in A. sucordt (4.3 m 2 /h) nd C. sempervirens site hd the lowest mount of sl re (3.8 m 2 /h) in compred to other plnttion sites Biomss production The results of Duncn test of ove- nd elowground iomss etween studied plnttion sites re shown in fig 3. These results indicted tht iomss production of studied species ws significntly different fter 18 yers of plnttion. Estimted oveground iomss ws significntly higher in A. sucordt nd A. velutinum plnttion sites thn C. sempervirens site. The results of comprison of elowground iomss were similr to tht of oveground iomss nd took the order: A. sucordt > A. velutinum > C. sempervirens (Fig 3). Totl mount of iomss production (t the ge of 18 yers) in A. velutinum, A. sucordt nd C. sempervirens plnttions were estimted round , nd tons per hectre respectively. Aoveground Biomss (t/h) Belowground Biomss (t/h) Fig 3- Comprison of ove- nd elowground iomss of three plnttion sites 3.3. Biomss C storge In fig 4 significnt differences cn e oserve etween iomss C storge tht we estimted in our studied plnttion sites. Biomss C storge in C. sempervirenss plnttion site ws significntly lower thn other plnttion sites nd they took order: A. sucordt ( t/h) > A. velutinum ( t/h) > C. sempervirens (22.91 t/h). The yerly rte of C storge clculted round: 23.41, nd (t/h/yr) for A. sucordt, A. velutinum nd C. sempervirens respectively. Biomss C (t/h) Fig 4- Comprison of iomss C storge of three plnttion sites Scholrs Reserch Lirry 6

7 Moslem Akrini et l Arch. Appl. Sci. Res., 212, 4 (1): DISCUSSION 4.1. The most productive species in studied re In north of Irn, forest plnttions re estlished to provide industril wood requirements. Other generl gols of these forest plnttions re to eliminte or llevite soil erosion nd wter loss in wtersheds, to restore degrded lnds nd some other environmentl purposes. Therefore, identifiction of suitle species for such purposes in ech specific re is very essentil. In our studied re C. sempervirens hd the lowest nd A. sucordt hd the highest survivl rte. The results of comprison of DBH etween studied species were the sme nd A. sucordt nd C. sempervirens hd the highest nd lowest mount of DBH respectively. Syyd et l. [32], in Chmestn region, reported tht survivl rte of A. sucordt fter 7 yers of plnttion ws 7% which ws lower thn Populus deltoides. Also they reported tht the DBH of A. sucordt ws reduced when this species ws grown in comintion with P. deltoides s compred with monocultures ut the reltive proportion of P. deltoides did not further ffect tht result. Jcos nd Severeid [15], in southwestern Wisconsin, reported tht Americn chestnut hd more rpid height (47-77%) nd dimeter (5-14%) growth compred to lck wlnut nd northern red ok. The highest mount of crown dimeter ws oserved in A. velutinum plnttion nd it ws significntly lower in C. sempervirens. Syyd et l. [32] oserved higher crown dimeter in A. sucordt compred to P. deltoides. Our results showed tht totl height growth ws significntly different etween studied plnttion sites nd took the order: A. sucordt > A. velutinum > C. sempervirens. While, totl height growth of A. sucordt ws lower thn P. deltoides in the study tht otined y Syyd et l. [32] in this region. The mount of stem height to the se of the crown ws significntly higher in A. sucordt in comprison to other plnttion species. Also A. sucordt plnttion site hd the highest mount of stnd sl re nd the results took order: A. sucordt > A. velutinum > C. sempervirens. While, higher mount of sl re in P. deltoides compred to A. sucordt plnttion ws reported y Syyd et l. [32] in this region. Our results showed significnt differences in iomss production of studied species. Aoveground nd elowground iomss production of A. sucordt nd A. velutinum were lmost twice the iomss production of C. sempervirens plnttion. Different estimtes re ville on iomss production of common plnttion species. For exmple, in 1 yers old P. tremuloides stnd (1267 stems/h), totl oveground iomss ws reported t 25.4 (t/h) y Rurk nd Bockheim [3]. Also Jcos et l. [14] reported tht Americn chestnut hd significntly greter iomss thn northern red ok nd lck wlnut on 8 yers old sites. Our results indicte tht in studied region A. sucordt my e the est option for plnttion progrms nd A. velutinum cn e the second priority in terms of wood production. Previous study in this region indicted tht these species lso hve gret influences on soil fertility nd nutrients nd their estlishment restored degrded soils [12]. Due to the low survivl rte, growth chrcteristics nd low iomss production, we do not recommend plnting of C. sempervirens in this region nd further reserches will e helpful to find the est re for estlishment of this species The role of lowlnd plnttions in cron mitigtion Tody, progrms re developing ll over the world tht provide finncil incentives to individuls conducting forest mngement prctices tht increse the mount of C sequestered y Scholrs Reserch Lirry 61

8 Moslem Akrini et l Arch. Appl. Sci. Res., 212, 4 (1): their forest plnttions [14]. Regrding the oserved increse in the tmospheric concentrtion of CO 2 nd the glol climte question, forests offer two min options. First, the volume of tmospheric CO 2 my e reduced y incresing forest iomss. This my e chieved through n expnsion of forests-either y plnting currently unforested lnd, or y llowing the existing forests to ccumulte higher iomss. The second min pproch is to utilize forest directly s source of rw mterils for energy production, usully referred to s ioenergy, which is considered cron-neutrl energy source [6]. Duo to the lrge scle of forest plnttions nd nturl forests, north of Irn hs gret potentil for CO 2 mitigtion ctivities nd projects in the forestry sector. Soil C sequestrtion nd C stocks were estimted in few reserches [12] in this re, ut iomss C storge mong different plnttion species, regions nd mngement mesures hs not een crried out yet. Niu nd Duiker [23] found tht oveground tree iomss ccounts for out two thirds of the totl C sequestrtion potentil of fforesttion plnttions in the Midwestern U.S. The other one third of C cpcity ws pproximtely eqully distriuted over C in roots, forest floor, nd soil orgnic C pools. Our results indicted tht C. sempervirens hd lower iomss C storge thn other plnttion species. Krenzel et l. [17] estimted tree C storge in Pnmnin tek plnttion to e 126 t/h (fter 2 yers of plnttion) which is very lower thn iomss C storge tht we estimted for our studied species (fter 18 yers of plnttion). Afforesttion nd reforesttion produce lrge potentil for C sequestrtion. Niu nd Duiker [23] estimted tht out 52 (t C/h) could e sequestered in oveground tree iomss 2 yers fter fforesttion in the Midwestern U.S. The rte of iomss C sequestrtion for A. sucordt, A. velutinum nd C. sempervirens ws 23.41, nd (t/h/yr) respectively. Thus, C. sempervirens plnttions mke lower contriution to the C sequestrtion nd mitigtion of greenhouse gs emissions in this re thn other studied species. Different rtes of iomss C storge hve een reported for different species in world. For exmple, Fng et l. [6] estimted rte of (t/h/yr) for poplr plnttions in Chin. For Americn chestnut this rte ws 3.1 (t/h/yr) estimted y Jcos et l. [14] while Lmlom nd Svidge [18] estimted iomss C rte of 3.58 nd 3.3 (t/h/yr) for red nd white pine, respectively. Biomss storge rte ws estimted (t/h/yr) for Chinese fir plnttion [7] nd (t/h/yr) for Msson pine plnttion [8] in Chin. Compred to these results, our results showed tht there is gret potentil of iomss C storge in forest plnttions in north of Irn which cn hve significnt influence on CO 2 mitigtion. Mny environmentl conditions cn ffect C storge potentil even within reltively smll geogrphic re [6]. Mngement prctices (such s species selection, fertiliztion, irrigtion methods, ) cn esily ffect C storge of forest plnttions [16, 21]. Pul et l. [24] suggested tht rte of ccumultion of C ws dependent on nnul rinfll, they reported tht with verge nnul rte of sequestrtion of C in tree iomss nd litter during the first rottion of E. cldoclyx (or C. mcult) incresing from 3.68 to 4.72 (t/h/yr) s nnul rinfll incresed from out 5 to 75 mm. As with ny other ttempt to evlute rtes of terrestril C sequestrtion etween tree species or regions, vrition in oth plnting density nd site qulity mke direct comprisons regrding C uptke nd storge difficult [14]. This type of extrpoltion often occurs, however, due to the logisticl chllenge nd cost of collecting iomss informtion [39]. So sed on the lck of informtion out C storge potentil of different species nd the role of mngement options nd vried environmentl conditions on this potentil in north of Irn, more reserches will e helpful to increse our knowledge. Scholrs Reserch Lirry 62

9 Moslem Akrini et l Arch. Appl. Sci. Res., 212, 4 (1): CONCLUSION Our results showed tht lowlnd plnttions in north of Irn cn e very effective on reducing the tmospheric CO 2 concentrtions esides the role tht they ply in wood production for industries. Bsed on survivl rte, growth chrcteristic nd iomss production, we introduce A. sucordt s the est species for plnttion in this re. A. velutinum cn e the second priority due to the low significnt differences tht it showed in comprison to A. sucordt. But we do not suggest plnting of C. sempervirens in studied re nd more reserches will e helpful to find the est re for estlishment of this species. On the other hnd, compred to results of other reserches for commonplce species in the world, ll three studied species hd huge potentil for C sequestrtion in their iomss. Therefore, estlishment of such plnttions in north of Irn will ply fundmentl role in CO 2 mitigtion, environmentl protection nd incresing the ecosystem productivity. Acknowledgements The uthors would like to thnk Trit Modres University for finncil, lortory nd scientific supports. We re grteful to the Orgniztion of Forest nd Rngelnds nd Wtershed Mngement of Irn for ccess to field sites nd logisticl support. We pprecite S. Vrmesh for his dditionl helps during this reserch. REFERENCES [1] Anonymous, Oshtorvsh Forest Mngement Plnning, Orgniztion of Forest nd Rngelnds nd Wtershed Mngement, Islmic Repulic of Irn, 1994, 37 p (In Persin). [2] C.B.M. Arevlo, J.S. Bhtti, S.X. Chng, D. Sidders, Forest Ecology nd Mngement, 29, 257, 8, [3] S. Brown, C.A.S. Hll, W. Kne, J. Rich, M.C. Trexler, P. Woomer, Wter Air Soil Poll, 1993, 7, [4] M.G.R. Cnnell, Forestry, 1999, 72, [5] F. Due, E. Zgl, N. Stolpe, M. Espinos, Forest Ecology nd Mngement, 29, 257, 8, [6] S. Fng, J. Xue, L. Tng, Journl of Environmentl Mngement, 27, 85, [7] X. Fng, D.L. Tin, W.H. Xing, Scienti Silve Sinice, 22, 38, 3, [8] X. Fng, D.L. Tin, C.H. Xu, Journl of Centrl South Forestry University, 23, 23, 2, [9] M.J. Fitzsimmons, D.J. Pennock, J. Thorpe, Forest Ecology nd Mngement, 24, 188, [1] C.T. Grten, Biomss nd Bioenergy, 22, 23, [11] A.B. Guitrt, L.C.E. Rodriguez, Ecologicl Economics, 21, 69, [12] N. Hghdoost, M. Akrini, S.M. Hosseini, Y. Kooch, Annls of Biologicl Reserch, 211, 2, 5, [13] I. Hunter, Forest Ecology nd Mngement, 21, [14] D.F. Jcos, M.F. Selig, L.R. Severeid, Forest Ecology nd Mngement, 29, 258, [15] D.F. Jcos, L.R. Severeid, Forest Ecology nd Mngement, 24, 191, [16] J. Koskel, P. Nygren, F. Berninger, O. Luukknen, Implictions of the Kyoto Protocol for tropicl forest mngement nd lnd use: prospects nd pitflls. Tropicl Forestry Reports 22. University of Helsinki, Deprtment of Forest Ecology, Helsinki, 2, 13p. [17] M. Krenzel, A. Cstillo, T. Moore, C. Potvin, Forest Ecology nd Mngement, 23, 173, Scholrs Reserch Lirry 63

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