The world's forests are the focus of international attention because
of the many environmental issues being discussed recently. According to
FAO (2002), cited from Rashid (2004), the world’s forests are estimated
to cover 3.9 billion hectares or 29.8% of the earth’s land surface.
From this total, an estimated 1,751 million hectares or 44.9% are located
in the developed countries while the balance of 2,149 million hectares
or 55.1% are within the developing countries. About 95% of these forests
are natural forests while 5% being plantation forests.
As globalization increases, the forest plantation has the potential to
contribute to industrial wood and fiber in the coming decades. However,
natural forest will not be able to supply all the demands. Therefore,
plantations are expected to provide an increasing share of total industrial
requirements and may even contribute a larger than natural forests by
the end of this period (Hummel, 2001). Forest rehabilitation by introduction
enrichment plants is commonly practiced in Malaysia in regenerating degraded
land forest. However, the selection of the right species played a very
important in determining the successful rehabilitate of the degraded forest
land. The degraded forest land is referred to forests where trees are
removed and are being farmed in an unsuitable manner.
Rehabilitation using indigenous timber species on a larger scale usually
encountered the following obstacles; irregular supply and recalcitrance
of seeds and high variability in growth of seedlings of as yet unknown
genetic potential, as seedlings are raised from stumps or wildings (Wyatt-Smith,
Reforestation of logged over forests has been successfully implemented
in some Forest Reserves Areas in Selangor, Perak and Negeri Sembilan (Lall
Singh, 1970). Rehabilitation efforts in degraded land, was one of the
main agenda in the country forest replanting programme. Sabah Forestry
Development Authority (SAFODA) was chiefly created in 1976 to implement
the reafforestation of wastelands in shifting cultivation areas. Up to
date an area of 50,000 ha was planted with the Acacia mangium plantation.
This programme also established several trials plots to determine the
practicability of enrichment planting (Domingo, 1979). The experiments
were not successful with an average survival rate of only 20%. The best
trial showed an overall survival rate of 59%. The most abundant species
surviving was Dryobalanops lanceolata (Kapur) 74%, Dipterocarpus
caudiferus (Keruing) 61% and Parashorea tomentella (White seraya)
The current studies also focus on the enrichment planting but on a different
site with different soil characteristics. It aims on identifying on the
best species for plantation and rehabilitation among selected wood species.
Apart from that it also evaluates the quantitative information and to
identify the growth and survival rates of selected indigenous species
planted. Criteria for evaluation are based on good growth performance,
high survival rate and also maintenance costs.
Materials and Methods
Five indigenous species were selected for the study. These are the dipterocarp
and non-dipterocarp species comprising of Azadirachta excelsa, Cinnamomum
iners, Intsia palembanica, Hopea pubescens and Shorea leprosula.
The study area was located in Pasoh Forest Reserve Area, Negeri Sembilan
(about 120 km from Kuala Lumpur). It covers an area of 2,450 hectares
and was a logged and clear felled area (using the crawler tractor and
left idle). The experimental plot chosen (42 ha.) was a degraded logged-over
forest established in August, 1995. Various indigenous timber species
were planted. The mean annual rainfall for a ten years period (1994 to
2003) was 1233.83 mm and the area experiences rainy season in November,
October and April. The mean daily temperature was 20.3 to 30.7°C.
The mean monthly relative humidity of the area was about 80%. The soil
composed mainly of the Paleozoic sedimentary rocks, which is principally
characterized by limestone, quartize and shale (Wyatt-Smith, 1963). The
vegetation of the area was predominated by Intsia palembanica, Sindora
spp., Shorea spp. and Dipterocarpus spp., Macarangga
gigantea, Trema orientalis and Melastoma malabatricum (Johari,
An experimental design of Randomized Complete Block Design (RCBD) was
used to analyze the data obtained from three replications of 30x150 m
block. Each block subdivided into 30 subplots with 5x10 m each. In each
subplot, a total of 15 seedlings were line-planted at a spacing of 2x2
m. The total number of potted-seedlings planted was 1,350. Open planting
technique had been used.
The growth criteria measured were the diameters at breast height and
the total height of the planted wood spp. Diameter breast height (DBH)
taken at 1.3 m from root collar by using Digmatic Diameter Calliper. The
height of the plants measured from the root collar to the base of the
top bud by using Height poll and Haga. Measurement of the data was recorded
to two decimal points. The survival percentage of each species was also
Data was subjected to the analysis of Variance and Duncan’s Multiple
Range Test. An Analysis of Variance was used to evaluate the growth performance
of the species.
Table 1 shows the mean diameter at breast height (DBH),
mean total height, mean diameter and mean height increment of the Azadirachta
excelsa, Cinnamomum iners, Intsia palembanica, Hopea pubescens
and Shorea leprosula evaluated.
Survival Rate of Trees
From the results obtained the survival rate of all the 5 species studied
shows some variation after 9 years of cultivation. The survival rate varies
from species to species. The results as exhibited in Table
1 and Fig. 1 showed that the survival rate of Cinnamomum
iners (76.3%) was the highest followed by Azadirachta excelsa
(74.1%), Intsia palembanica (48.2%) and Hopea pubescens
(44.4%). The Shorea leprosula recorded the lowest survival rate
at only 20.7%. Of the five species studies, the non dipterocarp species
showed better survival rates as compared to the dipterocarp species.
||Survival rate of nine years old of five tree species
planted at open area
||Mean for total Diameter at Breast Height (cm), total
height, diameter and height increment after 9 years old of five tree
|All data taken from mean of three replicates. * Mean
for total DBH, total height and increment height (by column) are significantly
different (p≤0.05) by Duncan’s New Multiple Range Test
Growth Diameter Trees
From the Table 1, the highest mean increment of
diameter at breast height (DBH) for two years periods (2002-2004) (recorded
when the trees were at ages 7 to 9 years) by Azadirachta excelsa
which is 2.11 cm, followed by Shorea leprosula, Hopea pubescens,
Cinnamomum iners and Intsia palembanica which are 2.05, 2.02,
1.96 and 1.93 cm respectively. However, statistical analysis conducted
showed no significant difference (p = 0.05) between the increments of
Growth Height Trees
The highest mean increment of height (Table 1) for
two years periods (2002-2004) (recorded when the trees were at ages 7
to 9 years) was recorded by Azadirachta excelsa at 2.75 m and followed
by Shorea leprosula, Hopea pubescens, Intsia palembanica
and Cinnamomum iners at 2.32, 2.07, 1.61 and 1.54 m, respectively.
Statistical analysis showed a significant difference (p≤0.05) between
the increments of height except C. iners and I. palembanica.
A. excelsa also had the highest mean annual increment of height
is 1.38 m year-1. Meanwhile, S. leprosula, H. pubescens,
I. palembanica and C. iners have gained 1.16, 1.04, 0.81 and
0.77 m year-1, respectively.
The survival rate of the cultivated species depends very much on the
genetic and their adaptability to the environment. However, there are
two factors that influenced growth performance of species in forestland,
which are by edaphic and climatic factors. Edaphic factors refer to soil
properties such as soil texture, moisture content, bulk density, particle
density, organic matter and nutrient content. Environment factors like
weather condition, pest attack and animal distribution, planting technique,
weed competition and poor soil condition are the factors possibly lead
to variation in survival rate and growth performance (Evans et al.,
1992). In addition, growing space also contribute to the growth performance
(Zaki et al., 1998). According Zaki et al. (1999) the rehabilitation
of tropical rainforests: some experiences in Indonesia and Malaysia. growth
in terms of height and diameter increment are influenced by the big growing
space. However, this would most likely to promote weed or climbers to
grow and invade the site.
The mean increment in diameter and the tree height shows an almost similar
pattern except in the species of C. iners and I. palembanica
where they change places from mean diameter to tree height. Similar results
were obtained by Appanah and Weinland (1993) in their studies on same
indigenous wood species in ex-mining land.
The previous data collected in 2002 (Sainih, 2003) show the mean annual
increments height of 1.34, 1.83, 0.98, 0.74 and 0.65 m year-1,
respectively. In the present study, however, decreases in the mean annual
increment of height were observed. Appanah and Weinland (1993) also obtained
similar results in the annual increment in height for S. leprosula
and I. palembanica.
Cinnamomum iners (76.3%) shows the highest survival rate, followed
by Azadirachta excelsa (74.1%), Intsia palembanica (48.2%)
and Hopea pubescens (44.4%).
Azadirachta excelsa has the highest mean increament of diameter
at DBH at 2.11 cm, followed by Shorea leprosula, Hopea pubescens, Cinnamomum
iners and Intsia palembanica which are 2.05, 2.02, 1.96 and
1.93 cm, respectively.
Azadirachta excelsa possess the highest increament of height at
2.75 m and followed by Shorea leprosula, Hopea pubescens,
Intsia palembanica and Cinnamomum iners at 2.32, 2.07,
1.61 and 1.54 m, respectively.
Overall performance indicates that Azadirachta excelsa and Cinnamomum
iners have good performance both in survival rate and growth in the
open planting technique.