2022, Vol. 12, No. 2, 261 – 268 http://dx.doi.org/10.11594/jtls.12.02.12
How to cite:
Research Article
Fish Biodiversity and Water Quality of Tropical Forest Streams Adjacent to the Western Boundary of Kinabalu Park, Sabah
Chen Lin Soo 1, Hairul Hafiz Mahsol 2, Leonardo Jainih 1, Arman Hadi Fikri 1, Cheng-Ann Chen 3, Nur Syafiqah Shamsul Kamal 4
1Institute for Tropical Biology and Conservation, Universiti Malaysia Sabah, Jalan UMS, 88400 Kota Kinabalu, Sabah, Malaysia
2Faculty of Tropical Forestry, Universiti Malaysia Sabah, Jalan UMS, 88400 Kota Kinabalu, Sabah, Malaysia
3Borneo Marine Research Institute, Universiti Malaysia Sabah, Jalan UMS, 88400 Kota Kinabalu, Sabah, Malay- sia
4Forest Research Centre, Sabah Forestry Department, P.O. Box 1407, 90715 Sandakan, Sabah, Malaysia
Article history:
Submission September 2021 Revised September 2021 Accepted December 2021
ABSTRACT
Modification and degradation of habitats outside the boundaries of a national park may result in the park's integrity being compromised. Thus, the present study aims to document variation in freshwater fish and water quality of tropical forest streams ad- jacent to the western boundary of Kinabalu Park, Sabah. Concurrently, fish samples and environmental parameters were collected at six stations covering a total stream- line length of 10 km. The three most abundant species were Tor tambra (34.4%), Bar- bodes sealei (19.5%), and Lobocheilos ovalis (12.4%). Tor tambra exhibited a nega- tive allometric growth pattern (coefficient < 3) and was in poor to fair condition (0.8
< Fulton’s condition factor < 1.2). The highest fish abundance was found in down- stream stations with species addition. Metrics of diversity, such as Shannon's diversity index and the Margalef index of species richness, decreased as elevation increased from 100 to 600 metres above sea level. The water quality of the forest streams is good, classified as Class I and/or Class II by Malaysia's National Water Quality Stand- ards, except for ammoniacal nitrogen at station 6, which was classified as Class III.
Higher turbidity, orthophosphate, and ammoniacal-nitrogen values were found near the Podos village. In conclusion, the altitudinal gradient of fish biodiversity was ob- served in the forest streams near Kinabalu Park. Regular water quality monitoring of the downstream river is necessary, as indicated by the potential domestic impacts on the river.
Keywords:Biodiversity, Elevation, Freshwater fish, Forest stream, Kinabalu Park
*Corresponding author:
E-mail: [email protected]
Introduction
Kinabalu Park, gazetted in 1964 as the first na- tional park in the state of Sabah and later declared as Malaysia’s first World Heritage Site by UNESCO in 2000, is home to a diverse array of flora and fauna species [1, 2]. The park covers an area of 754 km2 with its main feature of two moun- tains, one of which is the highest mountain in Ma- laysia, Mount Kinabalu standing at 4,095.2 meters tall, and Mount Tambuyukon standing at 2,579 meters. The great altitudinal range of the Kinabalu Park provides a wide array of habitats from Dip- terocarps lowland and hill rainforest to montane
forest, sub-alpine forest, and scrub at the summit [3, 4]. Its altitudinal changes in the composition, diversity, and richness of flora and fauna have been widely recorded [5–9]. The changes are often associated with changes in environmental varia- bles related to the altitudinal gradient.
Since the nineteenth century, Vaillant's work has pioneered the documenting of freshwater fishes in Kinabalu Park[10]. In addition, more than three decades ago, researchers have been studying the distribution and population of fresh- water fish fauna within Kinabalu Park[6]. Despite
this, the survey of fish assemblages outside the boundaries of the Kinabalu Park is limited and patchy, owing to the constraints associated with conducting research in rural areas of Borneo. The boundaries of Kinabalu Park are delineated and demarcated on the ground encompassing the main bulk of Mount Kinabalu. Anthropogenic activities such as settlement, agriculture, and logging are taking place right up to the boundary of Kinabalu Park. Modifying and degrading habitats could lead to changes in fish stocks, biodiversity, and well- being[11-13].
The progressive change and degradation of ar- eas outside Kinabalu Park could lead to the loss of park integrity. In order to avoid possible detri- mental repercussions on Kinabalu Park, continu- ous monitoring and regulation of development in places outside the Park is necessary. Therefore, the purpose of this study is to explore the biodiversity of fish and selected environmental characteristics along the forest stream next to the western border of Kinabalu Park. Furthermore, the altitudinal gra- dients of mountainous forest streams directly in- fluence freshwater fish assemblages [14, 15].
Thus, the current study determined a small scale of altitudinal changes in fish assemblages and en- vironmental parameters from 100 m to 600 m above sea level (asl).
Material and Methods
The current study was carried out in forest
streams in Kadamaian, Kota Belud, Sabah. The area is located on Sabah's west coast, immediately northwest of Kinabalu Park (Figure 1). Freshwater fish samples and water quality were collected con- currently from six sampling stations located from upstream to downstream. The six stations were lo- cated within a 10-kilometer radius and ranged in elevation from approximately 100 to 600 metres above sea level. Station 1, which is the furthest up- stream, is near the Kinabalu Park boundaries. For- est streams flow through a variety of forest types, from lowland mixed dipterocarp forest, to upland mixed dipterocarp forest to lower montane forest.
Human settlements including the Podos Along the forest streams, human settlements such as the Podos Heritage Homestay and Podos village are found.
The fish samples were collected using an elec- trofishing device powered by a 1000 watts porta- ble generator (Elemax Honda SHX1000). Scoop nets (1 cm mesh size) were used to collect the stunned fish. The electroshocking procedure was carried across a 200-meter stream length. Fish were counted and identified in the field to the spe- cies level using the available taxonomic keys [16–
20]. Unidentifiable samples in the field were first fixed in 10% formalin and then preserved in 70%
ethanol for further study in the laboratory. Finally, the taxonomic status was confirmed with Fishbase [21] and Eschmeyer’s Catalog of Fishes [22].
Fresh specimens of Tor tambra, the most abundant
Figure 1. Study area and the six sampling stations located adjacent to the western boundary of Kinabalu Park, Sabah.
fish species, were measured for total length (TL) and weight (W) to the closest centimeter and gram.
Water samples were collected in triplicate us- ing acid-washed, cleaned, and dried sampling bot- tles. Nutrient analysis of orthophosphate (PO4-P) and ammoniacal-nitrogen (NH4-N) began imme- diately after sampling in the field using the ascor- bic acid method and salicylate method, respec- tively [23]. Prior to analysis, the water sample was filtered through a 0.7 µm Whatman GF/F filter pa- per. Turbidity and conductivity of water samples were measured in triplicate by using a turbidity meter (Thermo Scientific™ Orion™ AQ4500) and a multiparameter water quality meter (Xylem YSI Professional Plus), respectively.
Metrics of diversity including Shannon’s di- versity index (H) and Margalef index of species richness (D) of fish at each station were calculated using the formula below:
Shannon’s diversity index (H) [24]
H =∑NNilogeNi
N………..…… (1)
Margalef index of species richness (D) [25]
D = logS - 1
eN………...………… (2) where N = sample size, Ni = number of specimens per species, S = total number of species
The length-weight relationship (LWR) and gen- eral well-being of fish expressed by Fulton’s con- dition factor (K) of T. tambra, the most abundant fish species, were determined. The LWR of T.
tambra was established using the formula below:
W=aTLb ………...………… (3)
The LWR was expressed in the logarithmic form as below:
Log W=Log a + b Log TL ………...……… (4) The relationship's statistical significance was then determined using linear regression analysis with a p-value ≤ 0.05 and the constants ‘a’ and ‘b’ were obtained from the regression analysis. The Ful- ton’s condition factor (K) [26] was calculated us- ing the formula below:
K = W × 100
𝑇𝐿3 ………...………… (5)
Non-metric Multidimensional Scaling (NMDS) based on the Bray-Curtis similarity ma- trix was applied to compare fish assemblage struc- tures from upstream to downstream. The fish abundance data was Hellinger transformed prior to statistical analysis. Environmental variables (ele- vation, conductivity, turbidity, PO4-P, and NH4-N) were also incorporated into the NMDS. Stress value in NMDS was used to measure the goodness of fit where a stress value less than 0.2 was con- sidered a good fit. The Spearman's Rank-Order Correlation was performed to elucidate the signif- icant relationship between environmental parame- ters and fish biodiversity at a p-value ≤ 0.05. All the statistical analyses were carried out using the Paleontological Statistics software package (PAST, Palaeontological Association, 2001) and Statistical Software for Social Sciences (SPSS Version 24, SPSS Inc., 1995).
Results and Discussion
In the forest streams next to the Kinabalu Park's boundary, 281 fish individuals belonging to four families, 12 genera, and 14 species were col- lected (Table 1). T. tambra (34.5%), Barbodes sealei (19.6%), and Lobocheilus ovalis (12.5%) were the three most abundant Cyprinidae species.
T. tambra, also known as Pelian in Sabah, is a high-priced edible fish. In the current study, a few individuals with a long mental lobe were ob- served, and the fish was identified as T. tambra ra- ther than Tor tambroides by assuming synonymy between the two species [27–30]. The decrease in T. tambra abundance from upstream to down- stream direction supports previous findings that T.
tambra distribution is often restricted to the up- stream [31]. T. tambra was recently found in abun- dance in the upper Baleh River in Sarawak, where it was the most dominant species (18.1%) in the river [31]. Besides, Tor spp. is known to exhibit highly potamodromous behaviors with upstream spawning migrations [32].
The LWR analysis of T. tambra is expressed as W = 0.016TL2.768 in the present study (Figure 2). Significant linear regression with R2 close to 1 indicated that the total length and weight of T.
tambra fitted well into the linear model. T. tambra exhibited a negative allometric growth as indi- cated by the equation parameter ‘b’ value < 3.
Length-weight relationship of T. tambra in the Sa- bah forest stream is similar to those in the Sarawak forest stream [31] and rivers from the western re-
gion of Aceh Province, Indonesia [33]. The pre- sent study also demonstrated that approximately 69% and 22% of K values of T. tambra were found in the range between 0.8 and 1.0 and between 1.0 to 1.2 which indicates the fish were in poor and fair conditions, respectively [34]. The condition factor of T. tambra in the present forest stream is found similar to that recorded in the upper Baleh River, Sarawak [31]. Despite the significant eco- nomic and ecological importance of T. tambra, there is a considerable lack of knowledge about it,
and it is currently classified as ‘data deficient in the IUCN Red List [35]. However, the authors [35] suspected that the wild population of T. tam- bra is in decreasing trend due to overfishing, hab- itat modification, and pollution as consequences of logging, deforestation, and agriculture activities.
Hence, preserving the upper section of this forest stream is critical as a living habitat for T. tambra, which is abundant in the area.
Figure 3 depicts differences in fish community structure, with downstream stations (stations 5 and
Figure 2. Length-weight relationship analysis of Tor tambra caught from forest streams adjacent to the western boundary of Kinabalu Park, Sabah.
Figure 3. Ordinations of sampling stations by nonmetric multidimensional scaling (NMDS) based on the Bray- Curtis similarity matrix using fish species abundance data. A second matrix of environmental varia- bles was incorporated into the NMDS. The stress is goodness-of-fit metrics.
6) distinguished from upstream and midstream stations (station 1 to station 4). The present study showed that the number of species, Shannon’s di- versity index (H), and Margalef index of species richness (D) of fish increased with increasing dis- tance from the boundary of Kinabalu Park. The fish abundance was the highest in the downstream stations where a total of 88 and 101 individuals were caught at station 5 and station 6, respectively.
Species addition from one to three species count at high altitude stations (> 380 m asl) to more than ten species in downstream stations with low eleva- tion (≈ 117 m asl) had resulted in the highest fish
abundance at downstream stations, as supported by positive and significant correlations between fish abundance and number of species, Shannon’s diversity index (H), and Margalef index of species richness (D) (Table 2, Pearson’s R = 0.922 to 0.957, p-value < 0.05).
Altitude plays a major role in determining fish assemblages in the present forest stream adjacent to the Kinabalu Park. Elevation was significantly and negatively correlated with the number of spe- cies, Shannon’s diversity index (H), and Margalef index of species richness (D) (Table 2, Pearson’s R = -0.923 to -0.950, p-value < 0.05).
Table 1. Summary of fish assemblages in forest streams adjacent to Kinabalu Park's western boundary in Kadamaian, Kota Belud, Sabah
Species Station 1 Station 2 Station
3 Station 4 Station 5 Station 6
Kadama- ian area
N % N % N % N % N % N % N %
Cyprinidae
Barbodes sealei 0 0.0 0 0.0 0 0.0 0 0.0 42 47.7 13 12.9 55 19.6 Garra borneensis 0 0.0 0 0.0 0 0.0 0 0.0 6 6.8 6 5.9 12 4.3 Lobocheilus ovalis 0 0.0 0 0.0 0 0.0 0 0.0 5 5.7 30 29.7 35 12.5 Nematabramis ev-
eretti 0 0.0 0 0.0 0 0.0 0 0.0 7 8.0 2 2.0 9 3.2
Osteochilus chini 0 0.0 0 0.0 0 0.0 0 0.0 1 1.1 0 0.0 1 0.4 Paracrossochilus
acerus 0 0.0 0 0.0 0 0.0 0 0.0 0 0.0 14 13.9 14 5.0 Rasbora argyrotae-
nia 0 0.0 0 0.0 0 0.0 0 0.0 6 6.8 3 3.0 9 3.2
Rasbora hubbsi 0 0.0 0 0.0 0 0.0 0 0.0 10 11.4 0 0.0 10 3.6 Rasbora sp 0 0.0 0 0.0 0 0.0 0 0.0 0 0.0 1 1.0 1 0.4 Tor tambra 32 91.4 27 100.0 7 77.8 19 90.5 4 4.5 8 7.9 97 34.5 Gastromyzontidae
Gastromyzon mon-
ticola 3 8.6 0 0.0 2 22.2 1 4.8 6 6.8 21 20.8 33 11.7 Protomyzon gris-
woldi 0 0.0 0 0.0 0 0.0 1 4.8 0 0.0 0 0.0 1 0.4
Mastacembelidae Macrognathus kei-
thi 0 0.0 0 0.0 0 0.0 0 0.0 0 0.0 1 1.0 1 0.4
Nemacheilidae Nemacheilus oliva-
ceus 0 0.0 0 0.0 0 0.0 0 0.0 1 1.1 2 2.0 3 1.1
Number of species 2 1 2 3 10 11 14
Fish abundance 35 27 9 21 88 101 281
Shannon’s diversity
index (H) 0.3 0.0 0.5 0.4 1.8 1.9 1.9
Margalef index of
species richness (D) 0.3 0.0 0.5 0.7 2.0 2.2 2.3
The NMDS plot also demonstrates the relationship between elevation and fish abundance in the forest streams. The loss of fish diversity and richness as altitude increases is most likely due to a reduction in available habitat at high altitude stations. Be- sides, elevation was significantly and negatively correlated with conductivity (Table 2, Pearson’s R
= 0.813, p-value < 0.05). The variation in stream conductivity is most likely due to dissolved ions
influenced by the area's unique geological charac- teristics and anthropogenic interactions at the downstream stations [15]. Altitudinal changes in the composition and biodiversity of fish fauna have also been recorded recently in the Baleh River, Sarawak [15]. Nonetheless, the current study found an opposite trend in Sarawak Forest streams, where fish abundance was highest at high altitudes in the Sarawak Forest stream.
Table 2. The correlation between environmental and fish fauna factors in forest streams next to the western border of Kinabalu Park, Sabah
Eleva- tion (m)
Con- ductiv-
ity (µS/cm
)
Turbid- ity (NTU)
PO4-P (mg/L)
NH4- N (mg/
L)
Num- ber of species
Abun- dance
Shan- non’s diver- sity in- dex (H)
Margalef index of
species richness
(D)
Elevation (m) 1.000
Conductivity
(µS/cm) 0.813* 1.000
Turbidity
(NTU) -0.785 -0.486 1.000
PO4-P
(mg/L) -0.720 -0.425 0.545 1.000
NH4-N
(mg/L) -0.256 -0.138 -0.267 0.570 1.000
Number of
species -0.923* -0.575 0.840* 0.880* 0.301 1.000
Abundance -0.780 -0.392 0.783 0.936* 0.311 0.957* 1.000 Shannon’s
diversity in- dex (H)
-0.939* -0.611 0.821* 0.858* 0.295 0.989* 0.923* 1.000 Margalef in-
dex of spe- cies richness (D)
-0.950* -0.611 0.841* 0.837* 0.287 0.994* 0.922* 0.991* 1.000
* p-value ≤ 0.05
Table 3. Environmental parameters of forest streams adjacent to the western boundary of Kinabalu Park, Sa- bah, and classification of the parameters in accordance with Malaysia's National Water Quality Stand- ards (NWQS)
Station Elevation (m)
NH4-N (mg/L)
Class Conduc- tivity (µS/cm)
Class Tur- bidity (NTU)
Class PO4-P (mg/L)
Class
1 615 0.193 II 165.70 I 0.58 I 0.03 I
2 565 0.207 II 94.90 I 0.33 I 0.03 I
3 379 0.210 II 62.47 I 0.46 I 0.02 I
4 381 0.240 II 89.60 I 0.71 I 0.02 I
5 123 0.063 I 53.27 I 2.36 I 0.06 I
6 111 0.480 III 59.03 I 1.20 I 0.09 I
Table 3 summarized the environmental param- eters of the forest stream adjacent to the western boundary of Kinabalu Park, Sabah. The water quality of the forest streams is good, as most of the parameters studied are classified as Class I and/or Class II according to the National Water Quality Standards (NWQS) for Malaysia, except NH4-N at station 6 which is Class III. The water in the forest streams is clear, as evidenced by extremely low turbidity values, with an average of 0.9 NTU. The values are substantially lower than those recorded in Sarawak forest streams subjected to logging, where turbidity as high as 1000 NTU has been re- ported [36]. In NMDS ordination space, stations located at the downstream segment were associ- ated with high PO4-P and turbidity values. The higher concentrations of those parameters are most likely due to the proximity of the down- stream segment to the Podos village. The effects of domestic discharges on the water quality of a nearby body of water are well documented [37–
39].
Conclusion
Altitudinal changes in fish biodiversity and environmental parameters were discovered in for- est streams adjacent to the Kinabalu Park's west- ern boundary at elevations ranging from 100 m to 600 m above sea level. With increasing elevation, fish abundance, number of species, Shannon's di- versity index (H), and Margalef index of species richness (D) all decreased. The highest fish abun- dance was found in downstream stations with spe- cies addition. T. tambra (34.4%), B. sealei (19.5%), and L. ovalis (12.4%) were the three most abundant Cyprinidae species discovered in this study. The water quality of the forest streams adjacent to the Kinabalu Park's western boundary is good as indicated by Class I water quality for turbidity and PO4-P. Nonetheless, downstream stations near the Podos village had higher turbid- ity, PO4-P, and NH4-N values indicating the poten- tial impact of domestic wastes.
Acknowledgment
The authors gratefully acknowledge the field assistance from Simon Kuyun, Maxwell Kwang Sing Ginol, and Azrie Alliamat. The authors would like to thank the Universiti Malaysia Sabah (UMS) for funding this study through Accultura- tion Grant Scheme; SGA0099-2019. The authors would also like to thank the Institute of Tropical
Biology and Conservation (ITBC), Universiti Ma- laysia Sabah (UMS) and Sabah Parks for organiz- ing the Borneo Geographic Expedition 2019:
Kadamaian – Kinabalu Park in October 2019, and the expedition funder UMS through Grant No.
SDK0082-2019. This study was conducted with the approval of the Sabah Biodiversity Council [Access License Ref. - JKM/MBS.1000-2/1 JLD.3 (248)].
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