Co esponding au ho : John O uoma
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Ea ly-s age es o a ion ou comes unde ac i e and passi e ehabili a ion
in e en ions in a humid opical o es
John O uoma 1, *, Mag a e M Kaigongi 2, Humph ey Age i 3, Ne eoh Leley 4, Samson Ojunga 1 and Judy Ogenche 1
1 Kenya Fo es y Resea ch Ins i u e, Lake Vic o ia Basin Eco- egion Resea ch P og amme, P. O. Box 5199 - 40108, Kisumu,
Kenya.
2 Kenya Fo es y Resea ch Ins i u e, Cen al Highlands Eco- egion Resea ch P og amme, P. O. Box 20412 - 00200, Nai obi,
Kenya.
3 Depa men o Biological Sciences, Masinde Muli o Uni e si y o Science and Technology, P. O. Box 190 – 50100,
Kakamega, Kenya.
4 Kenya Fo es y Resea ch Ins i u e, Ri Valley Eco- egion Resea ch P og amme, P. O. Box 382 - 20203, Londiani, Kenya.
Wo ld Jou nal o Ad anced Resea ch and Re iews, 2025, 26(02), 1880-1888
Publica ion his o y: Recei ed on 28 Ma ch 2025; e ised on 05 May 2025; accep ed on 08 May 2025
A icle DOI: h ps://doi.o g/10.30574/wja .2025.26.2.1716
Abs ac
Res o a ion o deg aded o es s and landscapes is eme ging as a global conse a ion p io i y. Opinion is di ided,
howe e , whe he ac i e es o a ion is a be e app oach han passi e in e en ion in o es ecosys em ehabili a ion.
We assessed he a ia ion in woody species composi ion and s and s uc u e du ing he i s i e yea s o bo h ac i e
and passi e es o a ion in e en ions in a deg aded humid o es in wes e n Kenya. Passi e es o a ion en ailed na u al
egene a ion, while ac i e es o a ion comp ised plan ing a 5m, 1m and 0.3m spacing. The plo s we e p o ec ed om
epea incidences o dis u bance using enclosu es. Na u al egene a ion egis e ed a signi ican ly highe woody species
ichness (36.75±6.97) han ac i e es o a ion (12.75±1.75). I had a highe Shannon-Wiene di e si y index (3.05) han
ac i e es o a ion (2.32). Despi e up o 10,000 seedlings pe ha being plan ed unde ac i e es o a ion, woody s em
densi y was signi ican ly highe unde na u al egene a ion (21,789±7,087 s ems ha-1) han ac i e es o a ion
(13,118±1,857 s ems ha-1). Mean sapling heigh was highe unde na u al egene a ion (2.60±0.31 m) han ac i e
es o a ion (1.38±0.30 m). The esul s sugges ha passi e es o a ion in e en ions may be supe io o ac i e
es o a ion app oaches in ehabili a ing deg aded o es landscapes in he humid opics i epea incidences o
dis u bance a e con olled. The long-held iew ha ac i e es o a ion leads o g ea e woody species di e si y and
s and s uc u e may ha e been spu ed by he ac ha ecological es o a ion in e en ions a e o en ca ied ou in open
si es ha a e exposed o con inual incidences o dis u bance, which ends o hampe he ec ui men and su i al o
na u al eg ow h.
Keywo ds: Fo es deg ada ion; Ea ly-s age es o a ion; Na u al egene a ion; Ac i e es o a ion
1. In oduc ion
Fo es and landscape es o a ion has eme ged as one o he global p io i ies in he e a o he clima e change and
biodi e si y loss. I has a g ea po en ial o mi iga e some o he eme ging nega i e global impac s on mankind and
ecosys em se ices [1, 2]. In his ega d, he global communi y has come up wi h ambi ious in e na ional commi men s
o es o e a leas 350 million ha o deg aded lands by 2030 [3, 4]. Res o a ion e o s unde his ini ia i e appea o be
bea ing posi i e ou come, wi h he la es global o es esou ce assessmen epo indica ing a 9.6% decline in he ne
a e o o es loss du ing he pe iod 2010 – 2020 [5]. Despi e an o e all ne global o es loss o 4.7 million ha pe yea
du ing he pe iod, Asia, Oceania and Eu ope eco ded posi i e esul s [5, 6], while A ica and Sou h Ame ica e u ned
Wo ld Jou nal o Ad anced Resea ch and Re iews, 2025, 26(02), 1880-1888
1881
ne losses [7, 8]. The esul s om A ica and Sou h Ame ica sugges ha he opics could s ill be g appling wi h
achie ing a s able balance among sus ainable na u al esou ce o ake, selec ing sui able es o a ion me hods and
dedica ing adequa e esou ces o landscape es o a ion e o s. Key d i e s o ege a ion loss in he opics ha e been
iden i ied as weak con ols in o es y sec o go e nance, enc oachmen o subsis ence ag icul u e in o o es land,
inadequa e con ols in esou ce o ake, poo choice o es o a ion echniques and low in es men in o es es o a ion
in e en ions [9, 10, 11].
The Global Fo es Resou ces Assessmen 2020 demons a es ha app oxima ely nine y- h ee pe cen o global o es s
comp ise na u ally egene a ed a eas, while abou se en pe cen (an equi alen o 290 million ha) accoun s o plan ed
o es [5]. The epo iden i ies na u al egene a ion as a majo sou ce o o es es o a ion a he global le el, and o e s
a window o oppo uni y o passi e es o a ion as a p ima y landscape es o a ion in e en ion o esou ce-sca ce
con inen s, such as A ica, Sou h Ame ica and Asia. Opinion is di ided, howe e , whe he passi e es o a ion is a mo e
e ec i e o es es o a ion echnique han ac i e es o a ion [12, 13, 4].
I is gene ally ag eed ha bo h passi e and ac i e es o a ion echniques achie e good ou comes in ega d o enhancing
biodi e si y s a us and ecosys em se ices [4, 14]. Howe e , he wo es o a ion echniques come wi h unique
equi emen s and associa ed cos s. Passi e es o a ion is o en conside ed less expensi e, bu i equi es he p o ec ion
o he es o a ion si e om epea incidences o dis u bance, such as g azing, ampling, i es and wood ha es ing [15,
16, 17, 18]. I also ends o h i e in si es o less se e e dis u bance, which in mos cases e ain po en ial sou ces o
na u al eg ow h, such as emnan ees, li e ee s umps, a ich soil seed bank and emnan o es s ands in he icini y
[19, 12, 18]. The success o passi e es o a ion ends o diminish wi h inc ease in he se e i y o si e deg ada ion, which
in mos cases leads o loss o po en ial sou ces o na u al eco e y [12, 1, 20]. Ac i e es o a ion, on he o he hand,
o en equi es ela i ely mo e inancial and ope a ional esou ces o suppo he sou cing o ee seeds and
consumables o a ee nu se y, ee seedling p oduc ion, managing he seedlings un il hey a ain sui able plan ing size,
anspo ing he seedlings o he plan ing si e, and plan ing and main enance o he es o a ion si e un il he plan ed
seedlings can su i e on hei own [4, 6]. Gi en he many s ages and p ocesses in ol ed, ac i e es o a ion ends o cos
ela i ely mo e han passi e es o a ion. None heless, mos people s ill p e e i o na u al egene a ion [1, 5].
Despi e a gene al p e e ence o ac i e es o a ion by o es manage s, ew s udies ha e conduc ed a side-by-side
compa ison o he wo es o a ion echniques [13, 4, 6]. The ew s udies conduc ed ha e shown con adic ing esul s.
Some ha e epo ed highe plan di e si y o ac i e es o a ion [e.g., 13], while o he s ha e epo ed simila plan
di e si y o bo h passi e and ac i e es o a ion in e en ions [e.g., 17]. In his pape , we assessed he a ia ion in
woody species composi ion and s and s uc u e du ing he i s i e yea s o bo h ac i e and passi e es o a ion
in e en ions in deg ada ion ho spo s in he Kakamega-Nandi Fo es Ecosys em in wes e n Kenya. Findings o his
s udy a e expec ed o imp o e he unde s anding o he compa a i e ad an ages o bo h passi e and ac i e es o a ion
in he ehabili a ion o deg aded o es lands. Fu he , hey will ac as a guide o es o a ion manage s on how o in es
limi ed esou ces in o es and landscape es o a ion ini ia i es.
2. Ma e ial and me hods
2.1. S udy a ea
The s udy was ca ied ou in Kibi i in Vihiga Coun y and Kobujoi in Nandi Coun y be ween Ap il 2018 and Ma ch 2023.
The wo si es all wi hin he Kakamega-Nandi Fo es Ecosys em in wes e n Kenya. The o es ecosys em is he
eas e nmos block o he Guineo-Congolian ain o es [21, 18]. I is loca ed 0° 10’ N & 0º 21’ N and 34º 47’ E & 34º 58’
E a 1,600 o 1,700 m abo e sea le el [18]. The eas e n po ion o o es ecosys em, which is e e ed o as Sou h Nandi
Fo es , is loca ed in a ansi ion zone be ween he ain o es and he opical A omon ane o es [22, 23]. This ansi ion
zone is loca ed 0o 00´ & 0o 15´N and 34o 45´& 35o 07´E [24] and ises o an ele a ion o 2,000 m abo e sea le el [25]. The
a ea expe iences a ho and we clima e wi h a diu nal empe a u e ange 19oC o 25°C and an annual p ecipi a ion o
1,500 o 2,000 mm [26, 27].
The o es ecosys em is es ima ed o ha e o e 986 species o plan s, app oxima ely 300 species o bi ds and abou
se en endemic p ima e species [28]. The ain o es ege a ion comp ises a dis u bed p ima y o es , old-g ow h
seconda y o es , ela i ely younge seconda y o es s ands in di e en s ages o eco e y, comme cial o es
plan a ions and some open ields [25, 18]. O e 112 woody species ha e been eco ded in he old-g ow h o es and
hese include An ia is oxica ia Lesch. S ombosia sche le i Engl., Fun umia a icana (Ben h.) S ap , Cel is gomphophylla
Bake , Ficus exaspe a a Vahl and C o on megaloca pus L. [29, 28]. The g adual inc ease in ele a ion om opical
ain o es o opical a o-mon ane o es leads o a mino shi in plan species cha ac e is ics [23]. Some o he unique
woody species ha one encoun e s in he ansi ion zone o he a o-mon ane o es include Maca anga
Wo ld Jou nal o Ad anced Resea ch and Re iews, 2025, 26(02), 1880-1888
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kilimandscha icum, and Tabe naemon ana s ap iana, [24]. The o es ecosys em is classi ied as an Impo an Bi d A ea
wi h new bi ds species s ill being encoun e ed o e and abo e he 300 species eco ded so a [23]. App oxima ely
300,000 people bo de he o es ecosys em and di ec ly de i e hei sus enance om i [30]. Some o he esou ces
ha hey ob ain om he o es include pas u e o li es ock, uel wood, cons uc ion ma e ials, he bal medicine, ibe ,
and wild ui s and ege ables [21].
2.2. S udy design
The s udy employed a spli -plo expe imen al design. The main plo was si e p o ec ion using enclosu es. Sub-plo s
we e he a ious ee espacemen s unde ac i e es o a ion. Si e p o ec ion was in ended o s imula e na u al
egene a ion by elimina ing epea incidences o si e dis u bance and any o m o ex e nal in e e ence. I is impo an
o no e ha he same enclosu es also p o ec ed ac i e es o a ion plo s. The unp o ec ed a eas su ounding he
es o a ion plo s se ed as he con ol. Ac i e es o a ion plo s comp ised h ee spacing ea men s: 0.3 m, 1 m and 5
m spacing. Ele en woody species we e plan ed in he ac i e o es es o a ion plo s. The species comp ised ligh -
demanding seconda y succession pionee s, shade- ole an in e media es and la e-s age successional species. Thus,
oge he wi h na u al egene a ion and he con ol, he s udy consis ed o i e ea men s. Assessmen was ca ied ou
as desc ibed by Kaigongi e al. [31] in a 20m by 10m main plo o woody species wi h a diame e a b eas heigh (DBH)
la ge han 10 cm. Woody species wi h s em DBH less han 10 cm we e assessed in 10m by 5m sub-plo s. Seedlings and
saplings less han 1.5m in heigh we e assessed in 2m by 1m sub-plo s. The sub-plo s we e nes ed in he le -hand co ne
o he main plo . The ea men s we e eplica ed h ee imes in each o he wo si es.
2.3. Da a collec ion
Da a collec ion a ge ed woody species. Da a we e collec ed on species names, s em diame e a b eas heigh (DBH)
and sapling heigh on an annual basis. Seedlings and saplings o less han 1.5 m in heigh we e eco ded by species and
coun o s ems. Woody species ha could no be iden i ied by bo anic names we e eco ded by local names and hei
specimens ca ied o he he ba ium o con i ma o y iden i ica ion.
2.4. Da a analysis
Da a we e en e ed in Mic oso Excel o p ocessing and desc ip i e analysis o species ichness, woody s em densi y,
mean DBH, DBH size-class dis ibu ion and mean sapling heigh . The di e ence in woody species di e si y be ween
ac i e and passi e es o a ion was analyzed using he Shannon-Weine di e si y index [32, 18]. In-dep h da a analysis
was conduc ed in Gens a s a is ical so wa e e sion 21 o de e mine he signi icance o a ia ions in woody species
ichness, s em densi y, DBH and sapling heigh using analysis o a iance (ANOVA) a 5% signi icance le el. Pos -hoc
es s we e ca ied ou o sepa a e means using he Ryan–Eino –Gab iel–Welsch Mul iple Range Tes a 5% signi icance
le el [33].
3. Resul s
3.1. Flo is ic composi ion
3.1.1. Woody species ichness
A o al o 54 woody species om 29 amilies we e eco ded. These included ele en woody species ha had been plan ed
o ac i e es o a ion o he deg aded o es si es. The addi ion o 43 new woody species h ough na u al o es
egene a ion led o a signi ican a ia ion in woody species ichness among he i e es o a ion ea men s (F(1,4) =
13.85; p < 0.001). Pos hoc es s indica ed ha he a ia ion was a ibu ed o a signi ican ly highe woody species
ichness in plo s unde passi e es o a ion (Figu e 1). Apa om he ele en plan ed species, woody species ichness o
ac i e es o a ion plo s did no inc ease much. I was he e o e no signi ican ly di e en om con ol plo s.
Wo ld Jou nal o Ad anced Resea ch and Re iews, 2025, 26(02), 1880-1888
1883
Figu e 1 Va ia ion in woody species ichness in es o a ion plo s in he Kakamega-Nandi Fo es Ecosys em. AR5m =
Ac i e es o a ion a 5m spacing, AR1m = Ac i e es o a ion a 1m spacing, AR0.3m = Ac i e es o a ion a 0.3m
spacing, PR = Passi e es o a ion, and Con = Con ol plo
3.1.2. Woody species di e si y
The Shannon-Wiene di e si y index o woody species di e si y anged be ween 1.13±0.01 and 3.05±0.72 (Table 1).
Passi e es o a ion plo s had he highes Shannon-Wiene di e si y index. Among, ac i e es o a ion plo s, 0.3m spacing
had he highes Shannon-Wiene di e si y index. Con ol plo s had a ela i ely highe Shannon-Wiene di e si y index
han 5m and 1m ac i e es o a ion plo s.
Table 1 Woody species di e si y in es o a ion plo s in he Kakamega-Nandi Fo es Ecosys em
3.2. S and s uc u e
3.2.1. S em densi y
S em densi y anged be ween 396±29 and 21,789±7,087 a Yea 5 (Table 2). The a ia ion in s em densi y among he
i e es o a ion ea men s was no s a is ically signi ican (F(1,4) = 1.60; p = 0.226). Howe e , passi e es o a ion
egis e ed a ela i ely highe s em densi y han ac i e es o a ion.
Res o a ion in e en ion
Shannon-Wiene di e si y index
Ac i e es o a ion (5m spacing)
1.13±0.01
Ac i e es o a ion (1m spacing)
1.67±0.45
Ac i e es o a ion (0.3m spacing)
2.32±1.26
Passi e es o a ion (unplan ed, p o ec ed plo s)
3.05±0.72
Con ol (unp o ec ed, unplan ed a ea)
1.77±0.42
Wo ld Jou nal o Ad anced Resea ch and Re iews, 2025, 26(02), 1880-1888
1884
Table 2 S em densi y in es o a ion plo s in he Kakamega-Nandi Fo es Ecosys em
Res o a ion in e en ion
S em densi y (s ems pe ha)
Ac i e es o a ion (5m spacing)
396±29a
Ac i e es o a ion (1m spacing)
2,450±1,523a
Ac i e es o a ion (0.3m spacing)
13,118±1,857a
Passi e es o a ion (unplan ed, p o ec ed plo s)
21,789±7,087a
Con ol (unp o ec ed, unplan ed a ea)
2,017±569a
l.s.d. = 20,722.2 p = 0.226
3.2.2. Sapling heigh
Mean sapling heigh anged be ween 0.50±0.18 m and 2.60±0.31 m (Table 3). The di e ence led o a signi ican a ia ion
in sapling heigh among he es o a ion ea men s (F(1,4) = 7.76; p = 0.001). Pos -hoc es s e ealed ha passi e
es o a ion and ac i e es o a ion a 0.3 m spacing had signi ican ly g ea e sapling heigh s han he o he h ee
ea men s (Table 3).
Table 3 Mean sapling heigh in ehabili a ed deg ada ion ho spo s in he Kakamega-Nandi Fo es Ecosys em
Res o a ion in e en ion
Mean sapling heigh (m)
Ac i e es o a ion (5m spacing)
1.32±0.29ab
Ac i e es o a ion (1m spacing)
1.38±0.30ab
Ac i e es o a ion (0.3m spacing)
2.54±0.46b
Passi e es o a ion (unplan ed, p o ec ed plo s)
2.60±0.31b
Con ol (unp o ec ed, unplan ed a ea)
0.50±0.18a
l.s.d. = 0.97 p = 0.001
*Di e en le e s nex o nume ical esul s in he mean sapling heigh column deno e signi ican di e ence o mean
3.3. G ow h pe o mance o woody species in ac i e and passi e es o a ion
Table 4 Compa ing he g ow h pe o mance o se en bes pe o ming woody species in ac i e and passi e es o a ion
plo s in he Kakamega-Nandi Fo es Ecosys em. AR = ac i e es o a ion, PR = passi e es o a ion
T ee species
Mean ee heigh (m)
Mean ee DBH (cm)
AR
PR
AR
PR
Albizia gummi e a
1.71
2.25
0.73
0.40
C o on mac os achyus
1.65
2.21
1.05
0.73
C o on megaloca pus
3.14
3.23
0.98
0.90
Ha ungana madagasc iensis
2.90
3.77
1.56
1.60
Khaya an ho heca
2.17
2.00
0.60
0.50
Ma khamia lu ea
1.42
1.11
0.64
0.38
Spa hodea campanula a
3.26
3.31
1.23
1.01
A compa ison o he g ow h pe o mance o he ele en ee species used o aided o es es o a ion indica ed ha
Ha ungana madagasca iensis, Spa hodea campanula a, C o on megaloca pus, Khaya an ho heca and C o on
mac os achyus we e he as es g owing species. Being a ligh -demanding la e successional pionee , Ha ungana
madagasca iensis ou pe o med all he species in ac i e es o a ion plo s. The ou woody species oge he wi h Albizia
Wo ld Jou nal o Ad anced Resea ch and Re iews, 2025, 26(02), 1880-1888
1885
gummi e a and Ma khamia lu ea also happened o ha e ec ui ed na u ally in passi e es o a ion plo s. A compa ison
o he se en species in ac i e and passi e es o a ion plo s showed ha hey we e ela i ely alle in passi e es o a ion
plo s ha in ac i e es o a ion plo s excep o Khaya an ho heca and Ma khamia lu ea (Table 4). Despi e being alle ,
all he species had ela i ely smalle s em DBH in passi e es o a ion plo s han he case in ac i e es o a ion plo s
excep o Ha ungana madagasca iensis.
4. Discussion
4.1. Role o passi e es o a ion in pos -dis u bance o es eg ow h
The esul s o his s udy sugges ha passi e es o a ion pe o ms be e han ac i e es o a ion in s imula ing he
ec ui men and g ow h o na i e woody species. This is illus a ed by he signi ican ly highe woody species ichness
in passi e es o a ion plo s compa ed o he ma ginal inc ease in plo s in all he h ee ea men s unde ac i e
es o a ion. The negligible numbe o woody species in he con ol a ea sugges s ha passi e es o a ion is highly
dependen on si e p o ec ion om epea incidences o si e dis u bance. Si e p o ec ion is, howe e , no only c i ical o
na u al egene a ion, i is impo an also o ac i e es o a ion. The obse a ion also ends o explain he long s anding
deba e whe he delay in pos -dis u bance o es eg ow h is caused by si e quali y limi a ions o epea incidences o
dis u bance, such as g azing, ampling, i e o cu ing o saplings [1, 2]. The spon aneous inc ease in woody ec ui s,
sapling heigh and s em diame e upon he e ec ion o enclosu es in si es ha had been ba e o o e wo decades gi es
an indica ion ha he delay in pos -dis u bance o es eco e y was likely caused by epea incidences o dis u bance
a he han si e quali y limi a ions imposed by he ini ial dis u bance. I he delay had been caused by si e quali y
limi a ions, hen si e p o ec ion would no ha e had a spon aneous e ec on na u al o es egene a ion. As no ed by
Zahawi e al. [12] and Flo es & Holmg en [34], howe e , si e p o ec ion may no lead o immedia e na u al o es
eco e y in a si e ha has los na u al sou ces o egene a ion, such as li e ee s umps, emnan ees ha se e as
seed sou ces, and a iable soil seed bank.
Despi e illus a ing he me i s o si e p o ec ion in o es es o a ion, i has a key limi a ion ega ding he p ac icabili y
o e ec ing enclosu es o e la ge a eas because o he huge cos s in ol ed [12] and he likely ecological impac s on auna
[14]. In essence, o es manage s could be mo e p agma ic in iden i ying iable local o es p o ec ion s a egies ha
a e bo h a o dable and ecologically sound. In o de o succeed, he p o ec ion s a egies may ha e o add ess he
unde lying causes o o es deg ada ion [9, 10]. Fo ins ance, in an e ec o add ess uncon olled g azing, g azing
pe mi s ha a e issued o li es ock owne s may ha e o clea ly indica e he allowable li es ock ype, numbe o
li es ock pe mi ed and a eas a ailable o g azing a any gi en ime, as opposed o he cu en scena io whe e pe mi
holde s can ha e any numbe o li es ock and g aze hei li es ock in any pa o a o es . Al e na i ely, li es ock owne s
may be es ic ed o cu ing g ass in he o es and ca ying i o hei homes eads o hei li es ock. Such s a egies
would ensu e ha pos -dis u bance o es eg ow h is no impeded by manage ial decisions o lack he eo .
4.2. Passi e o ac i e es o a ion?
Al hough he Global Fo es Assessmen 2020 epo [5] sugges s ha ac i e es o a ion is p esen ly a ou ed o e
passi e es o a ion, he esul s o his s udy show ha bo h o es es o a ion echniques ha e a ole in ega d o woody
species es ablishmen and g ow h pe o mance in he humid opics. The p e e ence o any o he wo es o a ion
echniques should be guided by he ehabili a ion needs o a gi en deg aded o es si e because hey wo k bes unde
di e en si e condi ions [2, 34]. Fo ins ance, passi e es o a ion wo ks be e in deg aded o es si es which a e ich
in sou ces o egene a ion, such as emnan ees, a iable soil seed bank and / o s ump sp ou s, bu i ends o be less
e ec i e in deg aded si es whe e sou ces o egene a ion ha e been emo ed h ough p olonged cul i a ion o epea
o es i es [16, 17]. Ac i e es o a ion, on he o he hand, wo ks bes in si es ha ha e been exposed o ela i ely se e e
le els o o es deg ada ion, which end o lack po en ial sou ces o egene a ion. I can also be applied o enhance
woody species di e si y in si es whe e o es deg ada ion has signi ican ly educed ee species ichness [35, 36].
Howe e , i o en p esen s a challenge o high cos o si e es ablishmen and main enance o plan ed seedlings. The
challenge becomes mo e p onounced i plan ing is ca ied ou in a si e wi h high po en ial o na u al egene a ion
because plan ed seedlings end up being swamped by na u al eg ow h.
4.3. Selec ing sui able spacing o ac i e es o a ion
This s udy does no p o ide a conclusi e inding on a spacing egime ha can be conside ed mos sui able unde ac i e
es o a ion. The esul s sugges , howe e , ha 5 m spacing does no p o ide an imp essi e ou come in he sho e m.
The 0.3 m and 1 m spacing appea mo e p omising, bu hey aise ques ions ega ding he associa ed cos s o
es ablishmen . A spacing o 5m may be mo e sui able o assis ing na u al egene a ion o en ich woody species
Wo ld Jou nal o Ad anced Resea ch and Re iews, 2025, 26(02), 1880-1888
1886
di e si y, while 0.3 m and 1 m could be mo e ele an in si es whe e ac i e es o a ion is he only in e en ion. I would
be in e es ing o ind ou whe he ee g ow h pe o mance would a y signi ican ly a 1.5 m, 2 m and 3 m spacing
5. Conclusion
Passi e es o a ion appea s o be a mo e iable o es es o a ion me hod han ac i e es o a ion in landscapes ich in
sou ces o na u al egene a ion, such as li e ee s umps, emnan ees and a iable soil seed bank. I cos s ela i ely
less in e ms o inances and ope a ions and, ends o p ese e a g ea deal o he o iginal axa a he es o a ion si e.
Howe e , i only h i es unde condi ions o less se e e deg ada ion. Ac i e es o a ion, hough conside ed o be mo e
cos ly, becomes ine i able unde condi ions o se e e deg ada ion whe e po en ial sou ces o na u al egene a ion ha e
been los and he si e has shi ed o an al e na i e s able s a e. The choice o woody species is an impo an conside a ion
in ac i e es o a ion because mos o i s si es end o be open ields. Ligh -demanding, la e successional woody pionee s
end o pe o m be e in he ini ial s ages han shade- ole an species in ac i e es o a ion. In his ega d, a leas 20%
o he es o a ion species could be la e successional pionee species.
Compliance wi h e hical s anda ds
Acknowledgmen s
This wo k was suppo ed by he Kenya Fo es y Resea ch Ins i u e and UNEP h ough he SLM P ojec .
Au ho con ibu ions
JO and SO designed he s udy. NL and JO pa icipa ed in da a collec ion. JO and SO analyzed he da a. All he au ho s
pa icipa ed in manusc ip p epa a ion.
Disclosu e o con lic o in e es
All he au ho s decla e ha hey ha e no con lic o in e es .
S a emen o e hical app o al
The wo k p esen ed in his manusc ip deal only wi h o es ege a ion. I did no equi e e hical app o al.
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