Konservasi Tumbuhan Tropika: Kondisi Terkini dan ...

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UPT Balai Konservasi Tumbuhan Kebun Raya Cibodas. Konservasi Tumbuhan Tropika: Kondisi Terkini dan Tantangan ke Depan. Prosiding Seminar/UPT Balai.
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©2011 Indonesian Institute of Sciences (LIPI) UPT Balai Konservasi Tumbuhan Kebun Raya Cibodas

Konservasi Tumbuhan Tropika: Kondisi Terkini dan Tantangan ke Depan. Prosiding Seminar/UPT Balai Konservasi Tumbuhan. – Cibodas, 2011. xx + 564 hlm.; 21 x 29,7 cm

ISBN 978-979-99448-6-3 1. Konservasi 2. Tumbuhan Tropika

Penelaah

: Didik Widyatmoko, D.M. Puspitaningtyas, R. Hendrian, Irawati, Izu A. Fijridiyanto, Joko R. Witono, Risna Rosniati, Siti Roosita Ariati, Sri Rahayu, Titien Ng. Praptosuwiryo. Setting dan Layout : Musyarofah Zuhri, Neneng Ine Kurnita, Suluh Normasiwi, Masfiro Lailati, Destri, Wiguna Rahman. Desain Sampul : Kusetiawan

*UPT Balai Konservasi Tumbuhan Kebun Raya Cibodas Lembaga Ilmu Pengetahuan Indonesia (LIPI) Sindanglaya, Cipanas, Cianjur, Jawa Barat 43253 Telp.: +62263 512233, 520419; Fax.: +62263 512233 Email: [email protected] www.krcibodas.lipi.go.id

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PROSIDING Seminar Nasional “Konservasi Tumbuhan Tropika: Kondisi Terkini dan Tantangan ke Depan” Cibodas, 7 April 2011

ISBN : 978-979-99448-6-3

Penelaah: Didik Widyatmoko D.M. Puspitaningtyas R. Hendrian Irawati Izu A. Fijridiyanto Joko R. Witono Risna Rosniati Siti Roosita Ariati Sri Rahayu Titien Ng. Praptosuwiryo

Penyelenggara: UPT Balai Konservasi Tumbuhan Kebun Raya Cibodas – LIPI Bekerjasama dengan Perhimpunan Biologi Indonesia (PBI), Balai Besar Taman Nasional Gunung Gede Pangrango (BBTNGGP), dan SEAMEO BIOTROP

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PROSIDING Seminar Nasional “Konservasi Tumbuhan Tropika: Kondisi Terkini dan Tantangan ke Depan” Cibodas, 7 April 2011

Tidak dibenarkan mengutip ataupun memperbanyak seluruh maupun sebagian isi buku ini kemudian mendistribusikannya, tanpa izin tertulis dari penerbit.

Diterbitkan oleh : UPT Balai Konservasi Tumbuhan Kebun Raya Cibodas – LIPI Sindanglaya, Cipanas, Cianjur, Jawa Barat 43253 Telp.: +62263 512233, 520419; Fax.: +62263 512233 Email: [email protected] www.krcibodas.lipi.go.id cetakan 2011© ISBN : 978-979-99448-6-3

Penelaah : Didik Widyatmoko, D.M. Puspitaningtyas, R. Hendrian, Irawati, Izu A. Fijridiyanto, Joko R. Witono, Risna Rosniati, Siti Roosita Ariati, Sri Rahayu, Titien Ng. Praptosuwiryo. Setting & Layout : Musyarofah Zuhri, Neneng Ine Kurnita, Suluh Normasiwi, Masfiro Lailati, Destri, Wiguna Rahman. Desain Sampul : Kusetiawan

Seminar Nasional HUT Kebun Raya Cibodas Ke-159

ISBN 978-979-99448-6-3

SURVIVORSHIP AND GROWTH OF EIGHT NATIVE TREE SPECIES DURING THEIR EARLY STAGE AT A RESTORED LAND WITHIN GEDE PANGRANGO NATIONAL PARK, INDONESIA Wiguna Rahman1, Fitri Kurniawati1, Eka A.P. Iskandar1, Imawan W. Hidayat1, Didik Widyatmoko1, Siti Roosita Ariati2 1

UPT Balai Konservasi Tumbuhan Kebun Raya Cibodas, LIPI; 2 Pusat Konservasi Tumbuhan Kebun Raya Bogor, LIPI E-mail: [email protected] Abstrak

Kebun Raya Cibodas-LIPI pada tahun 2009 telah melakukan restorasi hutan seluas 4 ha di kawasan Resort Bodogol, Taman Nasional Gunung Gede Pangrango. Keragaan delapan jenis pohon lokal sebagai framework species untuk melakukan restorasi hutan telah dimonitor. Jenis-jenis pohon tersebut yaitu Altingia excelsa Noronha (Rasamala), Alstonia scholaris (L.) R.Br. (Lame), Castanopsis argentea A.DC. (Saninten), Dacrycarpus imbricatus (Blume) de Laub. (Jamuju), Magnolia blumei Prantl. (Manglid), Syzygium lineatum (DC.) Merr. & L.M. Perry. (Ki Sireum), Schima wallichii Choisy (Puspa), dan Sloanea sigun (Blume) K.Schum. (Beleketebe). Keragaan tanaman dinilai berdasarkan kesintasan dan laju pertumbuhan tanaman. Hasil pengamatan selama satu tahun pertama menunjukkan bahwa rata-rata kesintasan tanaman yaitu 85.71%. Jenis pohon yang memiliki kesintasan paling tinggi yaitu Ki Sireum (96.66%), sedangkan yang terendah yaitu Jamuju (66.66%). Untuk pertumbuhan tanaman, terdapat perbedaan yang nyata pada laju pertumbuhan tinggi tanaman (F(7,205)=12.711), lebar tajuk (F(7,205)=7.494), dan diameter leher batang (F(7,205)=13.251) antar jenis. Secara keseluruhan, keragaan terbaik di tahun pertama ditunjukkan oleh Jamuju, diikuti oleh Ki Sireum, Rasamala, Lame, Puspa, Manglid, dan Saninten. Jenis Beleketebe menunjukkan keragaan yang kurang baik. Perbedaan ukuran semai pada saat ditanam mempengaruhi laju pertumbuhan tanaman dan keragaan tanaman. Hal ini ditunjukkan dengan adanya korelasi negatif antara ukuran tanaman pada saat tanam dengan laju pertumbuhan tanaman. Untuk itu diperlukan pengujian lanjutan untuk menentukan ukuran optimum semai sebagai bahan restorasi. Kata kunci: Restoration, Native trees, Gede Pangrango National Park INTRODUCTION Land use changes have been projected to become one of the major drives for biodiversity loss and threats (Sala et al., 2000). In many places in the tropics, natural habitats have been converted into agricultural lands and a large proportion of them have seriously been degraded. Global annual rates of deforestation range from 14% (Dobson et al., 1997). In Indonesia, deforestation rates have continuously been increasing, from 2.3% per year between 1990 and 2000 to 4.5 % per year between 2003 and 2006 indicating a serious decline in the primary forest areas (Koh & Wilcove, 2007; Pusat Inventarisasi dan Perpetaan Hutan, 2008). Some findings showed that protected areas (such as national parks) are effective refuges to stop land clearing and protect tropical biodiversity (Bruner et al.,2001). However, some evidence from Indonesia indicated that the establishment of protected areas only reduce the deforestation rates from large-scale mechanized logging but not from agricultural encroachment (Gaveau et al., 2007). Eventhough degraded protected areas are able to

maintain forest re-growth but it goes slowly, depending on the disturbance level. The slow processes of primary succession can be accelerated by conducting an artificial intervention through ecological restoration (Dobson et al., 1997). The main goal of ecological restoration is to create a self-sustaining ecosystem that has a similar degree with the reference ecosystem without further assistance (SER, 2004). Some attributes that should have existed on the target restored habitats are the presence of indigenous species and integration with the existing landscape. A feasible way to be used to accommodate those attributes is by planting native tree species. These native tree species are expected to attract seed dispersing animals that will subsequently disperse available seeds to enrich the restored area. This method is called the framework species method (Tucker & Murphy, 1997; Elliott et al., 2000; Alvarez-Aquino et al., 2004, Ramirez-Marcial et al., 2010). Gede Pangrango National Park (GPNP) is the oldest of national park in Indonesia where degraded land problems existed, particularly caused by agricultural encroachment. This park is 500

Seminar Nasional HUT Kebun Raya Cibodas Ke-159

located in West Java Province, Indonesia, with elevation ranges from 700 to 3000 m. It is the upperstream area of Cisadane and Ciliwung watersheds. Degraded lands in this area will inhibit land productivity, increase landslide risks, and increase sendiment supply to the two watersheds. This will subsequently increase flood risk at the lowerstream areas. Cibodas Botanic Garden has a unique opportunity for conducting and scaling up forest restoration activities in the facing of accelerating climate change and biodiversity loss. In 2009 Cibodas Botanic Garden initiated a program of restoration covering an area of 4 ha degraded land in the upperstream area of Cisadane watershed within Gede Pangrango National Park. This paper discusses the monitoring results conducted for eight native tree species within the restored studied site during their early stages (within a period of 12 months). METHODS Study Area The restored area is located in the Bedogol Resort of Gede Pangrango National Park (GPNP) (06o46'.241" S; 106o 50'.447" E) ranging from 620 to 709 m asl. Part of the restored area is still an active agricultural land while the rest is abandoned agricultural area. The agricultural land in this area now belongs to GPNP. Historically, this land belonged to the Perum Perhutani (Unit III), a public enterprise that has a concession to manage timber production from 1978 to 2003 in this area. Three major tree timber species have been planted monoculturely in this area, consisting of Altingia excelsa (Rasamala), Agathis damara (Damar), and Pinus merkusii (Pinus).

ISBN 978-979-99448-6-3

After harvesting time in 2003, the opened areas were since then occupied by local farmers until now, where the area is now undertaken by the GPNP. Farmers planted various annual crops, such as corn, cassava, chilli, beans, etc. The abandoned agricultural area was dominated by agricultural weeds such as Sida acuta, Mikania micrantha, Ageratum conyzoides, Stachytarpeta indica, Eupathorium odoratum, and Phragmites sp. Site characteristics are shows in Table 1. Seedling Establishment A total of 2400 seedlings of 8 native tree species were transplanted randomly on the 4 ha land 2009. The tree species were Altingia excelsa, Alstonia scholaris, Castanopsis argentea, Dacrycarpus imbricatus, Magnolia blumei, Schima walichii, Sloanea sigun, and Syzygium lineatum. Two hundred and forty individual plants were sampled proportionally (i.e. 30 individuals of each species) in order to measure the plant survival and growth. Each sampled plant (individual) was tagged with a plastic label and the position was recorded and mapped. Measurement of Seedling Growth Seedling survival, plant height, crown width, and root colar diameter were periodically monitored (3 times within a period of 12 months). Survivorship was estimated from the proportion of seedling survived at the final measurement. Plant height was measured using a ruler from root colar to the apical meristem. Crown width was measured using a ruler at the widest range. Diameter of root colar was measured using a dial calliper at the stem base.

Table 1. Characteristics of the Restored Site Soil Characteristics Soil pH

(0-10 cm) (10-20 cm) Organic Matter (%) (0-10 cm) (10-20 cm) Bulk density (g/cm3 ) (0-10 cm) (10-20 cm) Sand (%) Silt (%) Clay (%) Land Slope (o) Air temperature (oC)

Restored site

Neighbour Forested Site

5.27 4.75 6.73 6.48 0.66 0.67 9.11 49.69 41.20 48-60 23.3-33.0

5.10 4.76 9.86 10.2 0.56 0.72

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Seminar Nasional HUT Kebun Raya Cibodas Ke-159

Estimation of growth rates over the studied time is calculated by the Relative Growth Rates (RGR) by measuring growth in terms of increasing rate in size per unit of initial size. The formula used to calculate RGR follows Alvarezaquino et al. (2004):

RGR 

(ln X final  ln Xinitial ) time interval

where X final and X initial are the seedling height, crown width, and root colar diameter at initial and final measurement. We also measured Pearson’s correlation index to find relationship between initial plant size and the RGR. By combining the mean values of survival rates with % RGR will provide an index of relative performance. The relative performance index (RPI) was calculated using a modified Elliot et al. (2000): hRGR cRGR rRGR   S RPI   x x x x100 max.S max.hRGR max.cRGR max.rRGR

where S is mean percentage of survival rates, hRGR is mean percentage of height RGR, cRGR is mean percentage of crown width RGR, and rRGR is mean percentage of root colar diameter RGR. The maximum value is 100. RESULTS Plant Survival and Growth Rates Initial sizes of planted seedlings were varied among species (Fig. 1). The range of mean values of the initial seedling height, crown width, and root colar diameter were 34.30-135.92 cm, 31.53-47.15 cm, and 4.05-17.91 mm, respectively. The range of mean values of seedling height, crown width, and root colar diameter after 12 months were 85.97-181.52 cm, 49.88-116.89 cm, and 8.93-20.56 mm, respectively. Syzygium lineatum possessed the highest mean of seedling height and crown width, both of initial size and 12 month after transplanted. On the other hand, Dacrycarpus imbricatus had the shortest mean of seedling height and root colar diameter, both of initial size and at final measurement. The mean survival of planted seedlings of all species was 85.71%. The highest survival rate was recorded on Syzygium lineatum (96.66%), while the lowest survival rate occured on Dacrycarpus imbricatus (66.66%) (Table 2). Significant differences were also found in growth rates across the studied species (Table 2). The

ISBN 978-979-99448-6-3

range of mean values of height, crown width, and root colar diameter RGR were -0.08 to 0.92 cm cm-1 yr-1, 0.14 to 94 cm cm-1 yr-1, and 0.1 to 0.79 mm mm-1 yr-1, respectively. There were negative correlations between initial size and RGR values (Table 3). Overall, the correlations were fairly strong for the initial height vs height RGR and initial root colar diameter vs root colar diameter RGR, but was weak for the initial crown width vs crown width RGR. The correlation was strong on the height of Magnolia blumei and crown width of Syzygium lineatum. Overall, the best performing species was Dacrycarpus imbricatus, followed by Syzygium lineatum, Altingia excelsa, Alstonia scholaris, Schima walichii, Magnolia blumei, and Castanopsis argentea. Sloanea sigun performed poorly in this early periods. DISCUSSION Based on our evaluation, this area is not suitable to be used as an agricultural land particularly for cultivating annual crops. Based on land suitability classes for annual crops, such as corn, cassava, or chili, the land slope should be less than 30o (Djaenudin et al., 2003). If the agricultural practice continues on going, it will increase soil erosion rates and landslides. This risk will increase with the increasing trend of rainfall in this area (World Bank, 2007). Within a period of 12 months, six landslide events occurred in the site. It is necessary to plant tree species to reduce the degradation. Our data indicated that all species planted, except Sloanea sigun, performed well in this area. Those species are feasible to be planted in such degraded sites. Surprisingly, although Dacrycarpus imbricatus seems to be planted in out of its natural habitat range, but it has best perfomance. In GPNP, D. imbricatus is distributed from 1400 to 2075 m asl (Bramasto, 2008), however this species can also be found at 200 m asl as reported in Lombok (de Laubenfels, 1988). Although D. imbricatus shows best performance, it has high mortality rates. This species is vulnerable to weed competition, especially with Imperata cylindrica. Weeding becomes necessary if this species is recommended for restoration/reforestation projects.

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200

ISBN 978-979-99448-6-3

125

(A)

(B)

175 100

125

M ea n (cm )

M ean (cm )

150

100

75

50

75

50 25

25 Error bars: +/- 1,00 SE

Error bars: +/- 1,00 SE 0

0 0

6

0

12

6

12

Months After Transplanted

Months After Transplanted

(C)

25

M ean (m m )

20

15

Figure 1. Mean (±SE) of (A) Plant Height, (B) Crown Width, and (C) Root Colar Diameter Measurement, of 8 Trees Species Used in Restored Degraded Land at Gede Pangrango National Park, West Java, Indonesia.

10

5

Error bars: +/- 1,00 SE 0 0

6

12

( ( ( (

) Altingia excelsa, ( ) Castanopsis argentea, ) Dacrycarpus imbricatus, ( ) Magnolia blumei, ) Alstonia scholaris, ( ) Schima walichii, ) Sloanea sigun, ( ) Syzygium lineatum.

Months After Transplanted

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Seminar Nasional HUT Kebun Raya Cibodas Ke-159

ISBN 978-979-99448-6-3

Table 2. Percentage of Survival, Mean (±SE) Relative Growth Rates (RGR) in Height, Crown Width, Root Colar Diameter, and Relative Performance Index (RPI) of 8 Tree Species Used in Restored Degraded Land at Gede Pangrango National Park, West Java, Indonesia. The Numbers (Mean±SE) Followed by Same Superscripts Letters on Each Coloumn are not Significantly Different. Species Altingia excelsa (Rasamala) Castanopsis argentea (Saninten) Dacrycarpus imbricatus (Jamuju) Magnolia blumei (Manglid) Alstonia scholaris (Lame) Schima walichii (Puspa) Sloanea sigun (Beleketebe) Syzygium lineatum (Kisireum)

RGR in Root Colar Diameter (cm cm-1 yr-1) 0.68±0.05 cd

12.25

90

0.18±0.08 b

RGR in Crown Width (cm cm-1 yr-1) 0.76±0.09 cde

76.66

0.04±0.11 ab

0.61±0.12 bcd

0.44±0.06 b

1.20

66.66

0.92±0.07 d

0.52±0.09 bc

0.78±0.03 d

36.41

90

0.11±0.09 ab

0.63±0.13 bcde

0.66±0.06 cd

6.02

93.33

0.12±0.05 ab

0.92±0.09 de

0.79±0.08 d

11.91

90

0.45±0.10

c

0.32±0.10 ab

0.52±0.06 bc

9.86

86.66

-0.08±0.07 a

0.14±0.07 a

0.10±0.05 a

-0.14

96.66

0.28±0.04 bc

0.94±0.09 e

0.76±0.06 d

28.30

F(6,205)= 12.711; p