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Seasonal changes in mayfly communities and abundance in relation to water physicochemistry in two rivers at different elevations in northern peninsular Malaysia

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A field study was performed at rivers in Gunung Jerai forest reserve (Kedah, Malaysia) to assess seasonal changes in mayfly community structure and abundance in relation to altitude and water physicochemistry. Rivers at lower (Batu Hampar River) and higher (Teroi River) elevations were visited through dry and wet seasons in September 2007 to August 2008. Monthly visits were made to 20 sites on each river, and water and aquatic insects were sampled using D-pond aquatic nets. Water was warmer, more acid, and more turbid in Teroi River during wet season. Ammonia was the only nutrient exhibiting significant seasonal variations (greater during wet season). Chemical oxygen demand content was higher in Teroi River where biochemical oxygen demand content was low during wet season. Species richness was higher in Batu Hampar River, but displayed seasonal variations only in Teroi River. Among the eight families encountered, Baetidae was the commonest. Baetid abundance was usually high during wet season, and those belonging to the dominant genus (Baetis) were more abundant in Teroi River. Heptageniidae was the second commonest family; its predominant genus, Thalerospyrus was more abundant in Teroi River during dry season. Caenidae, Leptophlebiidae and Oligoneuriidae were only found in Batu Hampar River where their abundances peaked during dry season, i.e., Habrophlebiodes sp. and Isonychia sp. Ephemerellidae and Teloganodidae occurred only in Teroi River, with the first found only during dry season. Mayflies were recorded under very distinct physicochemical conditions, illustrating their potential usefulness for assessing water quality. Caenids, leptophlebids, oligoneurids ephemerellids and teloganodids seem to be particularly sensitive to temperature, acidity, turbidity, chemical oxygen demand and biochemical oxygen demand, parameters that varied with river altitude.
... In Malaysia, ephemeropterans' larvae have been incorporated as freshwater biomonitoring tools in rivers of Gunung Jerai, Kedah (Suhaila et al., 2011), Telipok River, Sabah (Kamsia et al., 2007), Langat River, Selangor (Azrina et al., 2006), Semenyih River, Selangor, (Yap et al., 2003), and Kerian River Basin, Perak (Che Salmah et al., 2001). Out of all the ephemeropterans, genus Baetis is classified as the most sensitive group (Arimoro & Muller, 2010). ...
... In this present study, the greatest abundances of Baetis species was collected from Sungai Ara followed by Sungai Jelai, Kurau and Ayer Itam and was confirmed by the attribute values. Large number of Baetis sp. was collected from Sungai Ara suggesting that this ephemeropterans are tolerant to the environmental differences (Suhaila et al., 2011). Different types of human activities at the nearby area might cause changes in abundances and composition of Baetis species (Arimoro et al., 2011;Arimoro & Ikomi, 2008). ...
... Another important factor affecting the abundances and distribution of Baetis sp. is the concentration of dissolved oxygen (Ward, 1992). B. illiesi, B. laetificus and B. minutus were positively correlated with the concentration of dissolved oxygen in the river similar to finding from Suhaila et al. (2011) that reported Baetis was strongly associated with DO levels in rivers running down from Gunung Jerai, Kedah. ...
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The abundance and distribution of seven Baetis sp. (Baetis gombaki, Baetis idei, Baetis illiesi, Baetis laetificus, Baetis lepidus, Baetis minutus and Baetis mirabilis) from Order Ephemeroptera (Family: Baetidae) in four rivers from Bukit Merah catchment area, Perak were studied. From this study, Sungai Ara was classified as the most preferred habitat and hotspot area for all the Baetis sp. Out of seven species, B. illiesi (120 individuals) was the dominant species while B. laetificus was the most sensitive taxa. This study indicates that abundance, distribution and composition of Baetis sp. in each river appeared to respond to the water quality parameters. B. idei showed positive correlation with water temperature (r=0.723, P=0.00) and Biochemical Oxygen Demand (r=0.719, P=0.00). B. gombaki was the least sensitive species as it is only correlated with water temperature (r=0.499, P=0.001). Sungai Kurau was considered as the less preferred habitat for Baetis. Copper (Cu) was positively correlated with the abundance of B. idei, B. lepidus and B. minutus (P<0.05) at a tolerable concentration (mean 0.64±0.4 ppm). It can be concluded that chemical parameters of the rivers do affect the abundance and diversity of Baetis species.
... In wet season, the abundance of ephemeropterans genera such as Baetis, Platybaetis, Campsoneuria and Thalerosphyrus increased tremendously. During the wet season in Teroi River, ephemeropterans such as Epeorus, Baetis, Platybaetis, Centroptilum, Tricorythus, Teloganodes and Crinitella were present (Suhaila et al. 2011). The improvement in water quality through reduction in organic matter or pollutant concentration (Bispo et al. 2006) provided more suitable environment for the ephemeropterans. ...
... The improvement in water quality through reduction in organic matter or pollutant concentration (Bispo et al. 2006) provided more suitable environment for the ephemeropterans. However, higher total suspended contents have increased survivorship of Thalerosphyrus, Campsoneuria, Epeorus, Baetis, Platybaetis, Centroptilum, Tricorythus, Teloganodes and Crinitella species (Suhaila et al. 2011). Suspended particles can serve as carriers of nutrients thus have effect on food availability (Dahlgren et al. 2004). ...
... Edmunds (1972) recognized Baetidae as the most opportunistic family. The greater abundance of Baetis present in Teroi River was probably attributed to the stable bedrock surfaces (Suhaila et al. 2011). For Thalerosphyrus, the flattened body and streamlined dorsum help them to scrape off periphyton on substrate surface (Rice & Greenwood 2001). ...
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Seasonal changes in Ephemeroptera, Plecoptera and Trichoptera (EPT) community was studied at rivers in Gunung Jerai Forest Reserve, Kedah, Malaysia. The rivers were visited monthly from September 2007 to August 2008 to sample aquatic insects using D-pond nets. More EPT were found in the wet season (10664 individuals) compared with the dry season (6599 individuals). In all rivers, ephemeropteran populations was highest during the wet season (z=-2.465, p=0.014). Meanwhile, the plecopteran population was low and almost constant throughout seasons in all rivers (z=-2.280, p=0.023). Trichopterans exhibited the highest peak of abundance in the dry season (z=-6.096, p=0.00). Concomitantly, higher diversity was recorded in the dry season (29 taxa) compared with 25 taxa recorded in wet season from all rivers. Tupah River had the most diverse EPT assemblage during the dry season. In wet season, the abundance of ephemeropterans genera such as Baetis, Platybaetis, Campsoneuria and Thalerosphyrus increased tremendously especially in Teroi River.
... Several studies have been conducted regarding seasonal influence on insects' population in tropical region for long time ago while the interest on seasonal effects in Peninsular Malaysia mostly is focused on Ephemeroptera, Plecoptera and Trichoptera (Suhaila et al. 2011(Suhaila et al. , 2014. This study took place in five selected rivers of Belum-Temengor Forest Complex (BTFC), one of the biggest protected areas in Perak state of Peninsular Malaysia. ...
Article
The plausible effect of seasonal change (wet and dry) on the structure of aquatic insect community was investigated at rivers in Belum-Temengor Forest Complex (BTFC), Perak, Malaysia. The amount of rainfall received was considered as seasonal changes in the tropical regions. The rivers were visited twice in dry and wet seasons to sample aquatic insects using rectangular aquatic nets. Their abundance and richness varied significantly between both dry and wet seasons (P = 0.000; Mann-Whitney U test). More aquatic insect was collected in dry seasons (17,633 individuals) compared to wet seasons (6,542 individuals). The aquatic insect abundance decreased tremendously during the wet seasons (45% reduction) and diversity showed fewer species richness in the wet season (98 genera) compared to the dry season (114 genera). The most affected taxa caused by the heavy water flow were Ceratopsyche sp. (family Hydropschidae and subfamily Limoniinae which huge reduction in density occurred during the wet season. Water temperature, BOD3, DO and COD were significantly different between seasons (Kruskal Wallis test, P < 0.05). The presence of phosphorus and ammonia-nitrogen in water during dry season had major influence on the aquatic insect composition while rainfall was the main factor that regulated the insect communities in wet seasons. ABSTRAK Kesan perubahan musim kering dan basah terhadap struktur komuniti serangga akuatik di kaji di sungai kompleks Hutan Belum-Temengor, Perak, Malaysia. Jumlah taburan hujan yang diterima dianggap sebagai perubahan musim bagi negara di rantau tropika. Sungai yang dipilih telah dilawati sebanyak dua kali pada musim kering dan musim basah bagi tujuan persampelan serangga akuatik dengan menggunakan jaring akuatik berbentuk segiempat tepat. Kelimpahan dan kekayaan spesies serangga akuatik adalah sangat ketara di kedua-dua musim kering dan basah (P = 0.000; Mann-Whitney U test). Lebih banyak serangga akuatik dikumpul pada musim kering (17,633 individu) berbanding musim basah (6542 individu). Kelimpahan serangga akuatik menunjukkan penurunan yang mendadak pada musim basah (45% Serangga 2020, 25(3): 101-115 Dhiya Shafiqah et al. ISSN 1394-5130 102 penurunan) dan kepelbagaian spesies juga adalah kurang pada musim basah (98 genus) berbanding musim kering (114 genus). Taksa yang paling terjejas disebabkan oleh arus air sungai yang deras adalah Ceratopsyche sp. (famili Hydropschidae), manakala subfamilii Limoniinae mengalami pengurangan individu yang tertinggi semasa musim basah. Suhu air, BOD3, oksigen terlarut dan COD menunjukkan perbezaan signifikan antara musim (Kruskal Wallis test, P < 0.05). Kehadiran fosforus dan ammonikal-nitrogen dalam air pada musim kering memeberikan kesan utama terhadap komposisi serangga akuatik, manakala kadar hujan pula merupakan faktor utama dalam mengawal komuniti serangga akuatik pada musim basah. Kata kunci: Bioindikator, pemantauan biologi, perubahan musim, sungai tidak terganggu.
... DO concentration is an essential limnological factor for the characterisation of aquatic ecosystems and the survival of aquatic life (Moura et al., 2011). Preceding research conducted at the Teroi and Batu Hampar rivers of Gunung Jerai forest reserve, Kedah by Hamid et al. (2011) reported that genus Baetis (family Baetidae) had a positive correlation with DO. Nevertheless, based on a study conducted in the lower catchment of the Kinabatangan River, Sabah, Harun et al. (2015) reported that Coenagrionidae and Libellulidae were declined in the high concentrations of DO. ...
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This study aimed to evaluate benthic macroinvertebrates assemblages using the application of ecological indices in the Rawang sub-basin of the Selangor River with reference to determining the impacts of aquaculture practices on benthic macroinvertebrates. In total, seven sampling sites were selected, namely Guntong (SR1), Guntong’s tributaries (SR2, control site), Kuang (SR3 and SR7), Gong (SR4), Buaya (SR5) and Serendah (SR6) Rivers. Sites were selected using a random sampling technique and the accessibility and proximity to aquaculture farms. Macroinvertebrates were sampled from April 2019 to March 2020 using an aquatic kick net, a hand spade, and a D-frame dip net. Water samples were also taken. Twenty-seven families belonging to the Annelida, Mollusca and Athropoda phyla were identified using taxonomic keys. Tubificidae was found to be the most dominant family (36.79%) followed by Chironomidae (28.84%). The highest number of individuals from family Tubificidae was recorded in Gong River, where effluent was discharged from an aquaculture farm. The total abundance of benthic macroinvertebrates increased with increased proximity to the aquaculture farm. Based on Biological Monitoring Working Party score value, the water quality of sampling sites in close proximity to the aquaculture farm was polluted as compared to the control location. Family Biotic Index score showed that all sites were substantially polluted with organic pollution, with the control site being much less polluted. In conclusion, benthic macroinvertebrates assemblage was affected by effluent originating from aquaculture farm outlets. It is therefore necessary to conduct aquaculture farming using methods that are deemed to be environmentally friendly.
... * Again the occurrence of Baetis sp. and Offadens sp. (Baetidae, Ephemeroptera) in abundance could suggest that they are tolerant to the anthropogenic influences ( Arimoro et al 2011, Suhaila et al 2011. Baetis sp. is also considered to change its assemblages based on its tolerant capability with the surrounding environment (Margolis et al 2001). ...
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Aquatic insects are widely used as indicator of water quality for many freshwater ecosystems. The present study was conducted seasonally in four different stretches of Umrisa Stream, Shillong, Meghalaya North-east India during 2015. Insects were collected using kick net method and all out search method. Analyses were done using Past software. A total of 9 orders, 25 families and 45 genera were recorded during the study. The diversity of aquatic insects was highest during pre-monsoon. Family Biotic Index (FBI) revealed good to excellent water quality across seasons and sites. Biological Monitoring Working Party Thailand (BMWPTHA1) Score and Average Score Per Taxon Thailand (ASPTTHA1) showed moderate and doubtful to good and clean water quality respectively. SingScore inferred Umrisa stream to have excellent water quality in all the seasons and sites. SIGNAL Score revealed the stream as mildly polluted to healthy habitat. This study revealed that different biological monitoring scores though differed with their results, overall reflected good water quality with signs of initiation of disturbance in the stream.
... Riparian arthropod predators such as birds and other vertebrates constitutes a threat to the abundance of aquatic insects including Mayfly larvae, as reported by Baxter et al. (2005), Murakami and Nakano (2001) and Paetzold and Tockner (2005). In addition, the presence of high amounts of organic matter such as suspended materials during summer favored by some genera EPT to thrive in the environment (Suhaila et al. 2011). Mann-Whitney U test found there was a significant difference in the distribution of Ephemeroptera in both seasons (z = -1.964, ...
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Temporal changes of Ephemeroptera, Plecoptera and Trichoptera (EPT) communities were investigated at the study area of Gunung Pulai Recreational Forest, Johor, Malaysia. Taxa diversity were also studied to determine the seasonality impact on certain benthic communities. Sampling of aquatic insects were carried out from November 2012 to July 2013 using rectangular dip net. As a result, more EPT were found during the dry season (1533 individuals) compared to wet season (321 individuals). Concomitantly, higher diversity was also recorded in the dry season. Among these three investigated orders, Trichoptera represented the most diverse community with three families recorded, followed by Plecoptera (2 families) and Ephemeroptera (1 family). Caddisfly family Hydropsychidae were found to be abundant in the study area. Therefore, seasonality impact on EPT assemblage at Gunung Pulai Recreational Forest is extremely evident.
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