**3. Results and discussions**

*MB* = 0.136 (*Ms*)1.070 (2)

**Forest types Locality Coordinates Slope Elevation Soil series**

28.100′ E to 0 4° 31.058' N, 102° 27.934′ E

24.469′ E to 04° 23.872' N, 102° 24.534′ E

04° 31.507' N, 102° 28.130′ E to 04°27.690' N, 102° 29.196′ E

Kuala Keniam 04° 31.148' N, 102°

= \_\_\_\_\_\_\_\_\_\_\_ <sup>1</sup> 0.124(Ms

*AGB* = *Ms* + *MB* + *ML* (4)

*BGB* = 0.0262 × *D*2.497 (5)

0.794) <sup>+</sup> \_\_\_1

<sup>125</sup> (3)

0–56° 133–139 m above sea level

0–40° 102–115 m above sea level

30–79° 292–340 m above sea level

Telemong

Telemong and Pagi

Gol and Tahan

ML

**Table 1.** Study area, forest types, locality, coordinates, slope, elevation and soil series in PNP.

\_\_\_1

**Figure 1.** Study areas of LDF, RF and HDF in PNP.

126 National Parks - Management and Conservation

2 Riparian Along Keniam and

Tembeling River

3 Hill dipterocarp Teresek Hill 04°23.888' N, 102°

**Study area**

1 Lowland

dipterocarp

#### **3.1. The total AGB, BGB and TTB for different types of forests**

The total AGB, BGB and TTB for lowland dipterocarp, riparian and HDF are shown in **Table 2**. From the **Table 2**, it appears that HDF recorded the highest AGB, BGB and TTB among study areas. This is because HDF consists of higher trees (*n* = 579) and number of trees with DBH of more than 80 cm was higher than the other two forests (14 trees/ha) (**Table 3**). Furthermore, dominant family in HDF based on basal area was Dipterocarpaceae with tree count of 58 from 579 trees (**Table 3**). These dipterocarp trees have diameter ranges from 10.8 to 103.5 cm. RF recorded the lowest AGB, BGB and TTB among the three forests as it recorded contains less number of trees (*n* = 285) and most of trees in RF have smaller diameter. Big-sized trees in RF with diameter more than 80 cm was lower than LDF and HDF (3 trees/ha) thus less contributed to tree biomass of RF.

As comparison with the previous studies, Cairns et al. [12] presented the AGB for 195 sampled trees with diameter of more than 10 cm in dry forest of Mexico's Yucatan Peninsula with value of 191.5 t/ha. Hikmat [13] conducted a study in three virgin jungle reserves in Mata Ayer, Bukit Bauk and Gunung Pulai each in 2 ha plot. A total of 2341, 2702 and 2070 trees with diameter greater than 5 cm were enumerated in Mata Ayer, Bukit Bauk and Gunung Pulai, respectively. From this study, he found that the AGB of each forest was 402.6, 551 and 320.57 t/ha, respectively. The BGB in Hikmat's [13] study was computed following method


**No. Family No. of individuals No. of genera No. of species**

Biomass and Carbon Stocks Estimation of Lowland Dipterocarp, Riparian and Hill Dipterocarp…

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129

**Table 2.** Total AGB, BGB and TTB in LDF, RF and HDF of PNP.

from [14] in which the root biomass was estimated to be one tenth of the AGB. In this case, the BGB values in Mata Ayer, Bukit Bauk and Gunung Pulai were 40.26, 55.12 and 32.06 t/ ha, respectively. The summation of AGB and BGB in the three study areas resulted in total tree biomass of 415.11, 323.33 and 579.05 t/ha. A study at Bangi Permanent Forest Reserve by Lajuni and Latiff [4] revealed that the AGB in 1 ha study plot was 362.13 t/ha derived from 1018 trees of more than 5 cm diameter. Most of trees in their study were distributed in class 5.0–14.90 cm (65.71%) causing the biomass value to be quite low than other studies.

#### **3.2. The analysis of mean of AGB, BGB and TTB between forests**

**Table 4** shows results from the analysis of AGB, BGB and TTB (t/ha) of lowland dipterocarp, riparian and HDF of PNP. Values presented in **Table 4** are mean values of AGB, BGB and TTB per plot. Result from ANOVA revealed that HDF recorded significantly higher mean of AGB, BGB and TTB than LDF and RF with the values of 499.97, 85.27 and 585.25 t/ha, respectively (p ≤ 0.05). This is because HDF comprises the highest number of tree and basal area compared to LDF and RF. Family Dipterocarpaceae contributed 10% from the total individuals in HDF. Mostly, dipterocarp trees in this forest especially *Shorea curtisii* have tree height ranges from 30 to 45 m and form the emergent layer of the forest. Even though Dipterocarpaceae was not the highest in term of tree density in the forest, they contributed the most in basal area with value of 13.91 m<sup>2</sup> /ha as these trees have larger diameter and height as compared to the other family. This value was the highest compared to LDF and RF. Therefore, this contributed to the higher values of AGB, BGB and TTB in HDF. Generally, basal area indicates the cross section of tree stem at breast height. Therefore, this value can be assumed as proportional to the stem biomass of a tree which also indicates the productivity of a forest [4]. This was supported by a result from Proctor and Newberry [15] in their study in four types of lowland forest in Gunung Mulu. They reported that TTB values in each forest types were in accordance to the value of mean basal area.

As for LDF, family Euphorbiaceae recorded the highest density (90 trees/ha), more than the highest family in HDF. However, the basal areas contributed only 3.10 m<sup>2</sup> /ha, considerably lower than family Dipterocarpaceae from HDF. Euphorbiaceae is known as a pioneer species and commonly have small diameter at the range of 10 to 30 cm in this forest. RF on the other hand, recorded the lowest number of trees compared to the other two forests (285 trees). Family Meliaceae recorded 26% (75 trees) from the total of 285 trees in RF and mostly composed of small trees with diameter 10 to 30 cm and seldom can exceed more than 40 cm, thus causing the tree biomass in RF to be lower than LDF and HDF.

Biomass and Carbon Stocks Estimation of Lowland Dipterocarp, Riparian and Hill Dipterocarp… http://dx.doi.org/10.5772/intechopen.76699 129


from [14] in which the root biomass was estimated to be one tenth of the AGB. In this case, the BGB values in Mata Ayer, Bukit Bauk and Gunung Pulai were 40.26, 55.12 and 32.06 t/ ha, respectively. The summation of AGB and BGB in the three study areas resulted in total tree biomass of 415.11, 323.33 and 579.05 t/ha. A study at Bangi Permanent Forest Reserve by Lajuni and Latiff [4] revealed that the AGB in 1 ha study plot was 362.13 t/ha derived from 1018 trees of more than 5 cm diameter. Most of trees in their study were distributed in class

**Study area AGB (t/ha) BGB (t/ha) TTB (t/ha)** Lowland dipterocarp forest (n = 419) 354.01 61.10 415.11 Riparian forest (n = 285) 276.13 47.21 323.33 Hill dipterocarp forest (n = 579) 493.77 85.27 579.05

**Table 4** shows results from the analysis of AGB, BGB and TTB (t/ha) of lowland dipterocarp, riparian and HDF of PNP. Values presented in **Table 4** are mean values of AGB, BGB and TTB per plot. Result from ANOVA revealed that HDF recorded significantly higher mean of AGB, BGB and TTB than LDF and RF with the values of 499.97, 85.27 and 585.25 t/ha, respectively (p ≤ 0.05). This is because HDF comprises the highest number of tree and basal area compared to LDF and RF. Family Dipterocarpaceae contributed 10% from the total individuals in HDF. Mostly, dipterocarp trees in this forest especially *Shorea curtisii* have tree height ranges from 30 to 45 m and form the emergent layer of the forest. Even though Dipterocarpaceae was not the highest in term of tree density in the forest, they contributed the most in basal area

other family. This value was the highest compared to LDF and RF. Therefore, this contributed to the higher values of AGB, BGB and TTB in HDF. Generally, basal area indicates the cross section of tree stem at breast height. Therefore, this value can be assumed as proportional to the stem biomass of a tree which also indicates the productivity of a forest [4]. This was supported by a result from Proctor and Newberry [15] in their study in four types of lowland forest in Gunung Mulu. They reported that TTB values in each forest types were in accordance

As for LDF, family Euphorbiaceae recorded the highest density (90 trees/ha), more than the

lower than family Dipterocarpaceae from HDF. Euphorbiaceae is known as a pioneer species and commonly have small diameter at the range of 10 to 30 cm in this forest. RF on the other hand, recorded the lowest number of trees compared to the other two forests (285 trees). Family Meliaceae recorded 26% (75 trees) from the total of 285 trees in RF and mostly composed of small trees with diameter 10 to 30 cm and seldom can exceed more than 40 cm, thus

highest family in HDF. However, the basal areas contributed only 3.10 m<sup>2</sup>

causing the tree biomass in RF to be lower than LDF and HDF.

/ha as these trees have larger diameter and height as compared to the

/ha, considerably

5.0–14.90 cm (65.71%) causing the biomass value to be quite low than other studies.

**3.2. The analysis of mean of AGB, BGB and TTB between forests**

**Table 2.** Total AGB, BGB and TTB in LDF, RF and HDF of PNP.

128 National Parks - Management and Conservation

with value of 13.91 m<sup>2</sup>

to the value of mean basal area.


**Table 3.** Number of families, individuals, genera, and species of HDF in PNP.

Kueh and Lim [16] estimated lower AGB value in comparison with this study. The study was conducted in the logged-over Air Hitam Forest Reserve where the pioneer species such as *Macaranga* spp., *Sapium* spp. and *Endospermum malaccense* were present in high density in the study area with an average DBH of 20.6–25.8 cm. The AGB for Air Hitam Forest Reserve was in the range of 83.69 to 232.39 t/ha. The lower value than the present study might suggest that the forest stand is in an early stage of succession and in the process of recovery after disturbances. Cummings et al. [17] revealed a result from their study in Brazilian Amazon Forest whereby mean of total AGB for open, dense and acetone forests were 313, 377 and 350 t/ha, respectively.

uniformly increased according to diameter class. HDF attained the highest total tree biomass for most diameter class except for diameter class 40.0–69.9 cm. RF achieved the lowest total tree biomass except for diameter class 50.0–69.9 cm whereas LDF only obtained the highest total tree biomass for diameter class 40.0–49.9 cm. With respect to **Figure 2**, lowland dipterocarp, riparian and HDF acquire highest biomass for diameter class of more than 70 cm with biomass value of 83.39, 70.58 and 202.72 t/ha, respectively. The biomass value for class >70 cm dominated 34, 38 and 35% of the total tree biomass in lowland dipterocarp, riparian and HDF, respectively. This indicates that tree diameter is a deciding factor for producing high biomass

Notes: Values are expressed as mean ± standard deviation. Means with same letter indicate no significant different.

**Riparian forest**

Biomass and Carbon Stocks Estimation of Lowland Dipterocarp, Riparian and Hill Dipterocarp…

**Hill dipterocarp forest (n = 20)**

131

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**n = 20)**

356.79 ± 121.01<sup>b</sup> 276.12 ± 35.59<sup>b</sup> 499.97 ± 221.70<sup>a</sup>

61.19 ± 586.60<sup>b</sup> 47.16 ± 24.58<sup>b</sup> 85.27 ± 160.61<sup>a</sup>

Total tree (TTB) (t/ha) 417.98 ± 200.54<sup>b</sup> 323.28 ± 35.89<sup>b</sup> 585.25 ± 236.06<sup>a</sup>

**Table 4.** Analysis of AGB, BGB and TTB between LDF, RF and HDF of PNP.

**Figure 2.** TTB by diameter classes in LDF, RF and HDF of PNP.

value in a forest.

Above ground (AGB)

Below ground (BGB)

(t/ha)

(t/ha)

**Biomass (t/ha) Lowland dipterocarp forest (n = 20)**

The total AGB of a study from Shanmughavel et al. [18] was 352.5 t/ha while root biomass was 69.9 t/ha. In contrast, Laurance et al. [9] estimated slightly higher AGB at lowland forest of Pasoh Forest Reserve which is 475 t/ha. A review by Malhi et al. [3] on carbon balance of different forest types i.e. Amazonian tropical rainforest, North American deciduous temperate forest and Canadian boreal forest revealed a variation in the AGB value between forests. The AGB value for tropical, temperate and boreal forests were 330–370 t/ha, 155–170 t/ha and 50–60 t/ha, respectively. The heterogeneity in the AGB values between forests was attributed to the climatic factors that affected the soil nutrients in the forest. In this case, due to the seasonality and temperature of boreal forest, nutrient availability is limited by slow decomposition in cold and water-freeze soil. Tropical forest on the other hand, even though has all year warm temperature but have poor soil nutrient and water availability as a result from high soil porosity and heavily leach soil. In general, higher tree biomass is expected on fertile soil simply because there are more resources available for tree growth. According to Laurance et al. [19] a high fraction of forest biomass could be associated with the most fertile soils as well as the tree size. Castilho et al. [20] claimed that texture was strongly associated with the variation in AGB value in their study area at Amazon Forest rather than soil nutrients. Soil texture influences the soil moisture, nutrient availability and nutrient cycling as well.

#### **3.3. The AGB, BGB and TTB distribution according to diameter classes**

**Figure 2** shows the above ground, below ground and total tree biomass in LDF, RF and HDF of PNP, respectively. Based on **Figure 2**, the total tree biomass in the study areas were not Biomass and Carbon Stocks Estimation of Lowland Dipterocarp, Riparian and Hill Dipterocarp… http://dx.doi.org/10.5772/intechopen.76699 131


**Table 4.** Analysis of AGB, BGB and TTB between LDF, RF and HDF of PNP.

Kueh and Lim [16] estimated lower AGB value in comparison with this study. The study was conducted in the logged-over Air Hitam Forest Reserve where the pioneer species such as *Macaranga* spp., *Sapium* spp. and *Endospermum malaccense* were present in high density in the study area with an average DBH of 20.6–25.8 cm. The AGB for Air Hitam Forest Reserve was in the range of 83.69 to 232.39 t/ha. The lower value than the present study might suggest that the forest stand is in an early stage of succession and in the process of recovery after disturbances. Cummings et al. [17] revealed a result from their study in Brazilian Amazon Forest whereby mean of total AGB for open, dense and acetone forests were 313, 377 and 350 t/ha,

Total 579 85 149

**No. Family No. of individuals No. of genera No. of species**

 Sterculiaceae 7 1 1 Theaceae 4 1 2 Trigoniaceae 1 1 1 Ulmaceae 1 1 1 Verbenaceae 10 1 1

**Table 3.** Number of families, individuals, genera, and species of HDF in PNP.

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The total AGB of a study from Shanmughavel et al. [18] was 352.5 t/ha while root biomass was 69.9 t/ha. In contrast, Laurance et al. [9] estimated slightly higher AGB at lowland forest of Pasoh Forest Reserve which is 475 t/ha. A review by Malhi et al. [3] on carbon balance of different forest types i.e. Amazonian tropical rainforest, North American deciduous temperate forest and Canadian boreal forest revealed a variation in the AGB value between forests. The AGB value for tropical, temperate and boreal forests were 330–370 t/ha, 155–170 t/ha and 50–60 t/ha, respectively. The heterogeneity in the AGB values between forests was attributed to the climatic factors that affected the soil nutrients in the forest. In this case, due to the seasonality and temperature of boreal forest, nutrient availability is limited by slow decomposition in cold and water-freeze soil. Tropical forest on the other hand, even though has all year warm temperature but have poor soil nutrient and water availability as a result from high soil porosity and heavily leach soil. In general, higher tree biomass is expected on fertile soil simply because there are more resources available for tree growth. According to Laurance et al. [19] a high fraction of forest biomass could be associated with the most fertile soils as well as the tree size. Castilho et al. [20] claimed that texture was strongly associated with the variation in AGB value in their study area at Amazon Forest rather than soil nutrients. Soil texture

influences the soil moisture, nutrient availability and nutrient cycling as well.

**Figure 2** shows the above ground, below ground and total tree biomass in LDF, RF and HDF of PNP, respectively. Based on **Figure 2**, the total tree biomass in the study areas were not

**3.3. The AGB, BGB and TTB distribution according to diameter classes**

respectively.

uniformly increased according to diameter class. HDF attained the highest total tree biomass for most diameter class except for diameter class 40.0–69.9 cm. RF achieved the lowest total tree biomass except for diameter class 50.0–69.9 cm whereas LDF only obtained the highest total tree biomass for diameter class 40.0–49.9 cm. With respect to **Figure 2**, lowland dipterocarp, riparian and HDF acquire highest biomass for diameter class of more than 70 cm with biomass value of 83.39, 70.58 and 202.72 t/ha, respectively. The biomass value for class >70 cm dominated 34, 38 and 35% of the total tree biomass in lowland dipterocarp, riparian and HDF, respectively. This indicates that tree diameter is a deciding factor for producing high biomass value in a forest.

**Figure 2.** TTB by diameter classes in LDF, RF and HDF of PNP.

As comparison between diameter class, sample trees at class 10.0–19.9 cm recorded the highest number of trees which is 256, 157 and 344 trees in lowland dipterocarp, riparian and HDF, respectively. However, this diameter class recorded lower biomass even though the number of trees was high. Diameter class >70.0 cm recorded the highest biomass though the number of trees was lower which are 5, 6 and 14 sample trees in lowland dipterocarp, riparian and HDF, respectively. Higher biomass value in diameter class >70.0 cm in HDF was due to large trees from family Dipterocarpaceae that constitute 11 trees of the total 14 trees from this diameter class.

A comparison with other studies indicated a similar result whereby a larger diameter class achieved a higher biomass in the study area. For example, a study from Kusin [21] at Jengka Forest Reserve found that trees at diameter class >65 cm dominated 36.64% of the total tree biomass in the study area with the biomass value of 247.12 t/ha. This diameter class comprised of 36 large trees from family Dipterocarpaceae. A study by [13] also obtained a result where large diameter class (≥75 cm) contained higher proportion of AGB in three virgin jungle reserves (VJR) in Peninsular Malaysia. The AGB values for diameter class ≥75 cm in Mata Ayer VJR, Bukit Bauk VJR and Gunung Pulai VJR were 143.21, 184.32 and 24.74 t/ha, respectively. Most of AGB values from his study were higher than the present study because trees with diameter ≥ 75 cm in his study areas were higher of which more than 20 trees.

statistically significant in the mean of AGB among families (p ≤ 0.05). This result indicated that there were no significant main effects of forest types on the values of AGB. There were, however, significant main effects of families on the AGB values, suggesting that families

2.96 ± 3.31 (n = 6)

3.61 ± 4.81 (n = 58)

**Forest (t/ha) Anacardiaceae Burseraceae Dipterocarpaceae Euphorbiaceae Leguminosae**

2.572 ± 5.76 (n = 17) 0.56 ± 0.99

Biomass and Carbon Stocks Estimation of Lowland Dipterocarp, Riparian and Hill Dipterocarp…

(n = 78)

0.60 ± 0.90 (n = 47)

0.37 ± 0.69 (n = 72)

0.73 ± 0.92 (n = 22)

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1.15 ± 2.26 (n = 30)

0.3823 ± 0.33 (n = 6)

1.04 ± 1.63 (n = 28)

1.83 ± 1.49 (n = 2)

0.64 ± 0.98 (n = 43)

The non-significant interaction between forest types and tree families is shown graphically in **Figure 3** which indicated by parallel line trend of mean of AGB distribution among families in each forest (P > 0.05). This indicates that the five families in the forest types in this study

From **Table 5**, the significantly different value of AGB between families (p ≤ 0.05) might due to the unbalanced sample trees in each family. Euphorbiaceae dominated the AGB among the five families in lowland dipterocarp, riparian and HDF. This is in agreement with the study by Ewel et al. [23] whereby Euphorbiaceae was the dominant species in alluvium, upland poor soil and intermediate quality soil forests in three young second growth forests in Sarawak.

**Figure 3.** Action between forest types and similar tree families in LDF, RF and HDF of PNP.

influence the AGB in any forest type in this study.

**Table 5.** Means AGB of similar families in LDF, RF and HDF of PNP.

respond similarly towards the forest types.

1.90 ± 2.98 (n = 11)

(n = 3)

(n = 25)

Riparian 2.51 ± 2.16

Hill dipterocarp 1.20 ± 2.55

Lowland dipterocarp

In contrast, Ewel et al. [22] reported a different result in hill forest of Ibam Forest Reserve, Pahang. The highest AGB value was recorded by diameter class 30.1–35.0 cm (30.51 t/ha), slightly lower than diameter class >70 cm (30.17 t/ha) in his study. The lower AGB value than the present study might be due to the lower number of trees in >70 cm diameter class. Similarly, Kueh and Lim [16] revealed that diameter class of 30.0–39.9 cm recorded the highest TTB in Air Hitam Forest Reserve. The TTB value of diameter class 30.0–39.9 cm was 232.73 t/ ha whereas for diameter class >70 cm was 151.54 t/ha. The differences of TTB values between diameter classes in their study were due to the different in tree density. Furthermore, the TTB value in their study for five compartments was higher than LDF and RF from the present study because higher number of trees at diameter > 70 cm (15 trees) compared to this study (five trees). A study by [18] at tropical seasonal rainforest in Xishuangbanna, China found that TTB value for diameter class >70 cm was 115.01 t/ha. This value was higher than LDF and RF but lower than HDF in this study. This might be attributed to the different forest type and environmental factor that cause the biomass to be higher.

#### **3.4. A comparison of similar tree families between forests**

In factorial ANOVA experiment, forest and families are considered as two types of treatments. In each treatment, forest for example, consist of three levels; lowland dipterocarp, riparian and HDF while family has five levels; Anacardiaceae, Burseraceae, Dipterocarpaceae, Euphorbiaceae and Leguminosae. Therefore, in this study, the factorial design is 3 × 5 factorial.

**Table 5** presents a result of comparison of five similar families based on AGB between lowland dipterocarp, riparian and HDF of PNP. From analysis of variance, there are no significant differences in the mean of AGB values among the forest types (p > 0.05) but


As comparison between diameter class, sample trees at class 10.0–19.9 cm recorded the highest number of trees which is 256, 157 and 344 trees in lowland dipterocarp, riparian and HDF, respectively. However, this diameter class recorded lower biomass even though the number of trees was high. Diameter class >70.0 cm recorded the highest biomass though the number of trees was lower which are 5, 6 and 14 sample trees in lowland dipterocarp, riparian and HDF, respectively. Higher biomass value in diameter class >70.0 cm in HDF was due to large trees from family Dipterocarpaceae that constitute 11 trees of the total 14 trees from this diameter

A comparison with other studies indicated a similar result whereby a larger diameter class achieved a higher biomass in the study area. For example, a study from Kusin [21] at Jengka Forest Reserve found that trees at diameter class >65 cm dominated 36.64% of the total tree biomass in the study area with the biomass value of 247.12 t/ha. This diameter class comprised of 36 large trees from family Dipterocarpaceae. A study by [13] also obtained a result where large diameter class (≥75 cm) contained higher proportion of AGB in three virgin jungle reserves (VJR) in Peninsular Malaysia. The AGB values for diameter class ≥75 cm in Mata Ayer VJR, Bukit Bauk VJR and Gunung Pulai VJR were 143.21, 184.32 and 24.74 t/ha, respectively. Most of AGB values from his study were higher than the present study because trees with diameter ≥ 75 cm in his study areas were higher of which more than 20 trees.

In contrast, Ewel et al. [22] reported a different result in hill forest of Ibam Forest Reserve, Pahang. The highest AGB value was recorded by diameter class 30.1–35.0 cm (30.51 t/ha), slightly lower than diameter class >70 cm (30.17 t/ha) in his study. The lower AGB value than the present study might be due to the lower number of trees in >70 cm diameter class. Similarly, Kueh and Lim [16] revealed that diameter class of 30.0–39.9 cm recorded the highest TTB in Air Hitam Forest Reserve. The TTB value of diameter class 30.0–39.9 cm was 232.73 t/ ha whereas for diameter class >70 cm was 151.54 t/ha. The differences of TTB values between diameter classes in their study were due to the different in tree density. Furthermore, the TTB value in their study for five compartments was higher than LDF and RF from the present study because higher number of trees at diameter > 70 cm (15 trees) compared to this study (five trees). A study by [18] at tropical seasonal rainforest in Xishuangbanna, China found that TTB value for diameter class >70 cm was 115.01 t/ha. This value was higher than LDF and RF but lower than HDF in this study. This might be attributed to the different forest type and

In factorial ANOVA experiment, forest and families are considered as two types of treatments. In each treatment, forest for example, consist of three levels; lowland dipterocarp, riparian and HDF while family has five levels; Anacardiaceae, Burseraceae, Dipterocarpaceae, Euphorbiaceae and Leguminosae. Therefore, in this study, the factorial design is 3 × 5 factorial. **Table 5** presents a result of comparison of five similar families based on AGB between lowland dipterocarp, riparian and HDF of PNP. From analysis of variance, there are no significant differences in the mean of AGB values among the forest types (p > 0.05) but

environmental factor that cause the biomass to be higher.

**3.4. A comparison of similar tree families between forests**

class.

132 National Parks - Management and Conservation

statistically significant in the mean of AGB among families (p ≤ 0.05). This result indicated that there were no significant main effects of forest types on the values of AGB. There were, however, significant main effects of families on the AGB values, suggesting that families influence the AGB in any forest type in this study.

The non-significant interaction between forest types and tree families is shown graphically in **Figure 3** which indicated by parallel line trend of mean of AGB distribution among families in each forest (P > 0.05). This indicates that the five families in the forest types in this study respond similarly towards the forest types.

From **Table 5**, the significantly different value of AGB between families (p ≤ 0.05) might due to the unbalanced sample trees in each family. Euphorbiaceae dominated the AGB among the five families in lowland dipterocarp, riparian and HDF. This is in agreement with the study by Ewel et al. [23] whereby Euphorbiaceae was the dominant species in alluvium, upland poor soil and intermediate quality soil forests in three young second growth forests in Sarawak.

**Figure 3.** Action between forest types and similar tree families in LDF, RF and HDF of PNP.

Since Euphorbiaceae was a fast-growing pioneer species, therefore most of the biomass in their study was recorded by species in this family.

Zani and Suratman [24] attained a similar result in which there was no significant different detected in the mean of AGB between five transect lines (20 × 100 m) in LDF of Kuala Keniam at PNP. In another study, Rayachhetry et al. [25] observed a similar result in a study to quantify the dry weight of the above ground components of *Melaleuca quinquenervia* trees in three different localities (dry, seasonally flooded, and permanently flooded) at southern Florida. From their study, the effects of locality on the above ground components (total wood, trunk, branch, leaf, seed capsule, and seed) were found to be no significant.

> Based on **Figure 4**, there was significant interaction between forest and species (p ≤ 0.05). This indicates that there is a variation in the AGB value among species. That is to say, species

Riparian 0.7770 (n = 1) 1.6045 ± 1.08 (n = 3) 5.2016(n = 1) 0.0908 (n = 1) 7.1628 ± 0.2 (n = 2)

*Ochanostachys amentacea*

Biomass and Carbon Stocks Estimation of Lowland Dipterocarp, Riparian and Hill Dipterocarp…

0.1998 (n = 1) 1.1029 ± 1.72

1.6559 ± 1.84 (n = 7)

*Pimelodendron griffithianum*

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0.6214 ± 2.15 (n = 4)

(n = 8)

*Shorea leprosula*

135

2.6389 ± 1.87 (n = 6)

0.6894 ± 0.85 (n = 11)

*Elateriospermum* 

0.9387 ± 1.51 (n = 26)

0.2989 ± 0.42 (n = 25)

*tapos*

Based on **Table 6**, *Shorea leprosula* from family Dipterocarpaceae appeared as the species with the higher AGB value among the five-similar species in lowland dipterocarp, riparian and HDF with the AGB of 0.69, 7.16 and 2.64 t/ha, respectively. Even though the presence of *Shorea leprosula* in each forest was not the highest, *Shorea leprosula* managed to attain higher AGB value due to the large DBH of sample trees. The presence of big trees with diameter of more than 80 cm contributed to the higher AGB values especially in the HDF. The mean AGB of *Shorea leprosula* in RF was higher than LDF and HDF because this forest consists of only two sample trees of *Shorea leprosula* therefore, mean AGB value per tree was higher. In fact, both sample trees of *Shorea leprosula* in this forest have large diameter of 69.0 and 69.1 cm that caused of higher AGB values for *Shorea leprosula* in RF. The higher AGB of *Shorea leprosula* in the RF is anticipated because the species is most common in lowland forest. That is to say, *Shorea leprosula* found in RF might be located at the continuum between lowland and RF. That is why only two trees of *Shorea leprosula* with large diameter were found in the RF plots.

Among the five species, *Elateriospermum tapos* recorded the highest number of trees in LDF and HDF but greatly lower in RF. Based on this result, it might suggest that *Elateriospermum tapos* grows abundantly in LDF and HDF rather than RF. However, mean AGB in RF was significantly higher than HDF (p ≤ 0.05) but not significant to LDF. This is due to similar reason

The AGB values and tree density varies among five similar species between lowland dipterocarp, riparian and HDF might be due to the environmental factors in the study areas (e.g., soil nutrient, topography, water, light). Each species adapts and respond differently to the limiting factors in the area Shono et al. [26]. For example, *Elateriospermum tapos* favors forest soil that is dry and less preferable on soil that often wet. This might be the reason the tree density

These five-similar species that can be found in all forests in this study were due to the adaptability of these species to the environmental factors in the areas. For example, *Shorea leprosula* is a dipterocarp species that can easily adapt to full sunlight and fast growing once the seeds have been germinated whereas C*anarium littorale* was capable to survive in full sunlight and

of *Elateriospermum tapos* in RF was lower than the other two forests.

behaves differently in different forest types.

**Table 6.** Biomass and carbon stocks of LDF, RF and HDF of PNP.

**Forest** *Canarium* 

Lowland dipterocarp

Hill dipterocarp *littorale*

2.4779 ± 3.05 (n = 5)

1.6048 ± 2.52 (n = 3)

as stated in the case of *Shorea leprosula*.

#### **3.5. A comparison of similar tree species between forests**

The result of comparison of five similar species between forests namely *Canarium littorale (*Burseraceae), *Elateriospermum tapos* (Euphorbiaceae), *Ochanostachys amentacea* (Olacaceae), *Pimelodendron griffithianum* (Euphorbiaceae) and *Shorea leprosula* (Dipterocarpaceae) based on AGB in lowland dipterocarp, riparian and HDF of PNP is presented in **Figure 4**. **Table 6** shows mean of AGB for five similar species in lowland dipterocarp, riparian and HDF of PNP. From analysis of variance, there are statistically significant differences in the mean of AGB values both in the forest types and species (p ≤ 0.05). This result indicated there were significant main effects of forests types and species on the AGB value suggesting that the AGB was influenced by the forest types and families.

**Figure 4.** Interaction between forest types and similar tree species in LDF, RF and HDF of PNP.

Biomass and Carbon Stocks Estimation of Lowland Dipterocarp, Riparian and Hill Dipterocarp… http://dx.doi.org/10.5772/intechopen.76699 135


**Table 6.** Biomass and carbon stocks of LDF, RF and HDF of PNP.

Since Euphorbiaceae was a fast-growing pioneer species, therefore most of the biomass in

Zani and Suratman [24] attained a similar result in which there was no significant different detected in the mean of AGB between five transect lines (20 × 100 m) in LDF of Kuala Keniam at PNP. In another study, Rayachhetry et al. [25] observed a similar result in a study to quantify the dry weight of the above ground components of *Melaleuca quinquenervia* trees in three different localities (dry, seasonally flooded, and permanently flooded) at southern Florida. From their study, the effects of locality on the above ground components (total wood, trunk,

The result of comparison of five similar species between forests namely *Canarium littorale (*Burseraceae), *Elateriospermum tapos* (Euphorbiaceae), *Ochanostachys amentacea* (Olacaceae), *Pimelodendron griffithianum* (Euphorbiaceae) and *Shorea leprosula* (Dipterocarpaceae) based on AGB in lowland dipterocarp, riparian and HDF of PNP is presented in **Figure 4**. **Table 6** shows mean of AGB for five similar species in lowland dipterocarp, riparian and HDF of PNP. From analysis of variance, there are statistically significant differences in the mean of AGB values both in the forest types and species (p ≤ 0.05). This result indicated there were significant main effects of forests types and species on the AGB value suggesting that the AGB was influenced

their study was recorded by species in this family.

134 National Parks - Management and Conservation

branch, leaf, seed capsule, and seed) were found to be no significant.

**Figure 4.** Interaction between forest types and similar tree species in LDF, RF and HDF of PNP.

**3.5. A comparison of similar tree species between forests**

by the forest types and families.

Based on **Figure 4**, there was significant interaction between forest and species (p ≤ 0.05). This indicates that there is a variation in the AGB value among species. That is to say, species behaves differently in different forest types.

Based on **Table 6**, *Shorea leprosula* from family Dipterocarpaceae appeared as the species with the higher AGB value among the five-similar species in lowland dipterocarp, riparian and HDF with the AGB of 0.69, 7.16 and 2.64 t/ha, respectively. Even though the presence of *Shorea leprosula* in each forest was not the highest, *Shorea leprosula* managed to attain higher AGB value due to the large DBH of sample trees. The presence of big trees with diameter of more than 80 cm contributed to the higher AGB values especially in the HDF. The mean AGB of *Shorea leprosula* in RF was higher than LDF and HDF because this forest consists of only two sample trees of *Shorea leprosula* therefore, mean AGB value per tree was higher. In fact, both sample trees of *Shorea leprosula* in this forest have large diameter of 69.0 and 69.1 cm that caused of higher AGB values for *Shorea leprosula* in RF. The higher AGB of *Shorea leprosula* in the RF is anticipated because the species is most common in lowland forest. That is to say, *Shorea leprosula* found in RF might be located at the continuum between lowland and RF. That is why only two trees of *Shorea leprosula* with large diameter were found in the RF plots.

Among the five species, *Elateriospermum tapos* recorded the highest number of trees in LDF and HDF but greatly lower in RF. Based on this result, it might suggest that *Elateriospermum tapos* grows abundantly in LDF and HDF rather than RF. However, mean AGB in RF was significantly higher than HDF (p ≤ 0.05) but not significant to LDF. This is due to similar reason as stated in the case of *Shorea leprosula*.

The AGB values and tree density varies among five similar species between lowland dipterocarp, riparian and HDF might be due to the environmental factors in the study areas (e.g., soil nutrient, topography, water, light). Each species adapts and respond differently to the limiting factors in the area Shono et al. [26]. For example, *Elateriospermum tapos* favors forest soil that is dry and less preferable on soil that often wet. This might be the reason the tree density of *Elateriospermum tapos* in RF was lower than the other two forests.

These five-similar species that can be found in all forests in this study were due to the adaptability of these species to the environmental factors in the areas. For example, *Shorea leprosula* is a dipterocarp species that can easily adapt to full sunlight and fast growing once the seeds have been germinated whereas C*anarium littorale* was capable to survive in full sunlight and water stress [26]. According to Pereira Da Silva et al. [27], many factors influence the tree growth in the forest. Usually, tropical tree species exhibits different behavior under different environmental conditions regardless of species or families. Macdicken and Brewbaker [28] agreed with this finding in which they found a significant different between site location and species interactions which indicate different environmental requirements for each species. In support to these findings, Brackand and Wood [29] provided a fact that tree growth was influenced by the environmental factors in the forest. Factors such as climatic, soil, topographic and competition combine to create a site. Therefore, the biomass value in a forest is indirectly affected by these factors because tree biomass value depends on the tree diameter.

The differences of estimated carbon storage among tropical forests might be due to some limiting factors such as species composition, soil fertility, disturbance history, successional stage and climate Kang et al. [31]. The AGB in the secondary forest would not be the same as the primary forest. Primary forest contains old-growth and large trees since this forest have never been disturbed whereas secondary forest that had been logged or naturally disturbed contains trees with smaller diameter. Therefore, the tree biomass in secondary forest is less than the primary forest. This was supported by Kang et al. [31] who conducted a study to quantify carbon stocks in primary and secondary forests of Bukit Timah Nature Reserve in Singapore. The result from their study revealed that primary forest obtained higher carbon stock than secondary forest with value of 337 and 274 t/ha, respectively. The values in their study were

Biomass and Carbon Stocks Estimation of Lowland Dipterocarp, Riparian and Hill Dipterocarp…

http://dx.doi.org/10.5772/intechopen.76699

137

In this chapter, the AGB, BGB and TTB of lowland dipterocarp, riparian and HDF have been estimated. Analysis of AGB, BGB and TTB between forests showed that means of AGB, BGB and TTB values in HDF were significantly higher than LDF and riparian (p ≤ 0.05). The distribution of AGB, BGB and TTB according to diameter class revealed higher AGB, BGB and TTB values in >70 cm class for all forests. HDF was highest in most diameter class except for 40.0–69.9 cm. LDF obtained highest biomass in 40.0–49.9 cm whereas RF for 50.0–69.9 cm. There was no significant interaction between lowland dipterocarp, riparian and HDF and five similar families (i.e. Anacardiaceae, Burseraceae, Dipterocarpaceae, Euphorbiaceae and Leguminosae) with (p > 0.05). However, the interaction between lowland dipterocarp, riparian and HDF and five similar species (i.e. *Canarium littorale (*Burseraceae), *Elateriospermum tapos* (Euphorbiaceae), *Ochanostachys amentacea* (Olacaceae), *Pimelodendron griffithianum* (Euphorbiaceae) and *Shorea leprosula* (Dipterocarpaceae) was significant at (p ≤ 0.05). The estimation of carbon storage in the study areas demonstrated HDF attained the highest carbon value in above ground, below ground and total tree with value of 246.88, 42.64 and

and Nazlin Asari1,2\*

lower than LDF and HDF but higher than RF from this study.

Nor Farika Zani1,2, Mohd Nazip Suratman1,2, Adzmi Yaacob<sup>3</sup>

\*Address all correspondence to: nazlin0023@salam.uitm.edu.my

1 Faculty of Applied Sciences, Universiti Teknologi MARA, Shah Alam, Malaysia

2 Centre of Biodiversity and Sustainable Development, Universiti Teknologi MARA,

3 Faculty of Plantation and Agrotechnology, Universiti Teknologi MARA, Shah Alam,

**4. Conclusions**

289.52 t/ha, respectively.

**Author details**

Shah Alam, Malaysia

Malaysia

#### **3.6. Carbon stocks**

Global climate change is the current major threat to the earth. Due to the rapid deforestation and land clearing and conversion that have been actively taking place since 1850 [3] the emission of CO2 keeps increasing. Referring to the report from National Research Council [30], these activities contribute 17% from the total CO<sup>2</sup> released to the atmosphere. However, it was reported that forests can remove twice the amount that is lost by deforestation. It was estimated that the total carbon pool in the forest ecosystems approximately 1150 Gt, of which 14% in temperate forests, 37% in tropical forests and 49% is in the boreal forests [3].

**Table 7** exhibits the carbon storage of lowland dipterocarp, riparian and HDF in PNP. The estimation of carbon storage within each forest was not greatly varies between different species or tree components. The carbon storage in HDF at 289.52 t/ha was higher than LDF and RF. LDF was 207.88 t/ha whereas the lowest was RF at 161.67 t/ha. Meanwhile, above ground carbon in HDF was 246.89 t/ha, in LDF was 177.29 t/ha while RF was 138.07 t/ha, respectively (see **Table 7**).

The carbon storage in HDF was the highest due to the higher biomass in this forest. This is because the tree density in HDF was higher compared to the other two forests types (*n* = 579).

As comparison to other study, Hikmat [13] found nearly the same result in three virgin jungle reserves (VJR) in Peninsular Malaysia. Carbon storage in Mata Ayer VJR, Bukit Bauk VJR and Gunung Pulai VJR recorded 221.43, 303.16 and 176.33 t/ha, respectively. In another study, [16] estimated carbon storage in Air Hitam Forest Reserve was 89.57 t/ha. This value was considerably lower than the present study because Air Hitam Forest Reserve was recovering from the past disturbances. Therefore, most of the sample trees were composed of small diameter trees with average diameter of 24.0 cm.


**Table 7.** Biomass and carbon stocks of LDF, RF and HDF of PNP.

The differences of estimated carbon storage among tropical forests might be due to some limiting factors such as species composition, soil fertility, disturbance history, successional stage and climate Kang et al. [31]. The AGB in the secondary forest would not be the same as the primary forest. Primary forest contains old-growth and large trees since this forest have never been disturbed whereas secondary forest that had been logged or naturally disturbed contains trees with smaller diameter. Therefore, the tree biomass in secondary forest is less than the primary forest. This was supported by Kang et al. [31] who conducted a study to quantify carbon stocks in primary and secondary forests of Bukit Timah Nature Reserve in Singapore. The result from their study revealed that primary forest obtained higher carbon stock than secondary forest with value of 337 and 274 t/ha, respectively. The values in their study were lower than LDF and HDF but higher than RF from this study.
