Potensi chironomidae sebagai penunjuk biologi di sungai rekreasi terpilih Janda Baik, Pahang, Semenanjung Malaysia

Satu kajian ke atas kepelbagaian chironomid (Diptera: Chironomidae) dalam ekosistem bebas cemar telah dijalankan di Janda Baik, Pahang, Semenanjung Malaysia. Kajian ini adalah untuk mengenalpasti penyebaran dan komposisi Chironomidae di tujuh sungai rekreasi terpilih di Janda Baik. Chironomid disampel menggunakan jaring Surber dan enam parameter kualiti air telah dianalisis iaitu oksigen terlarut (DO), permintaan oksigen biokimia (BOD5), permintaan oksigen kimia (COD), ammoniakal nitrogen (NH3-N), jumlah pepejal terampai (TSS) dan pH. Hasil kajian menunjukkan famili Chironomidae di Janda Baik diwakili oleh tiga subfamili iaitu Chironominae, Orthocladiinae dan Tanypodinae dengan jumlah individu sebanyak 10421. Chironominae dikenal pasti sebagai subfamili yang paling dominan iaitu sejumlah 9168 individu, manakala subfamili Tanypodinae (849 individu) merupakan kedua tertinggi diikuti dengan Orthocladiinae (404 individu). Polypedilum (Chironominae), Rheocricotopus (Orthocladiinae) dan Rheotanytarsus (Chironominae) adalah genus yang dominan di Janda Baik. Polypedilum spp. mendominasi enam daripada tujuh sungai kajian, manakala Rheocricotopus spp. didapati mendominasi satu sungai iaitu Sg. Kerul. Ujian CCA memperlihatkan pengaruh kandungan DO yang kuat dengan taburan Polypedilum dan potensinya untuk dijadikan sebagai penunjuk biologi untuk sungai kelas II ke atas

Biodiversity of benthic macroinvertebrates in Air Terjun Lata Kinjang, Chenderiang, Perak, Malaysia

A study on benthic macroinvertebrate diversity was conducted in Air Terjun Lata Kinjang, Chenderiang, Perak, Malaysia. Five stations were selected with a distance of approximately 500 metre interval. Three replicates of benthic macroinvertebrates and water samples were taken from each station. Result indicates that Air Terjun Lata Kinjang is in class I condition based on Malaysian water quality index. A total of two phyla, three classes, eight orders, 30 families, and 1177 individuals were successfully identified. The average Shannon Diversity Index, (H’) is 2.07, Pielou Evenness Index, (J’) is 0.46, and Margaleff Richness Index, (DMg) is (3.08). These values describe Air Terjun Lata Kinjang as in good conditions but macroinvertebrates are not uniformly distributed between stations. Biological Monitoring Working Party (BMWP) and Family Biotic Index (FBI) score are 150 and 4.75, respectively which also explain this stream as having good water quality. The CCA test was conducted to show environmental factors towards benthic macroinvertebrate distribution. The presence of Baetidae with a high abundance of the families shows the potential to be used as biological indicators of a clean ecosystem

Ketoksikan akut arsenik, kromium dan selenium terhadap moluska air tawar di Malaysia; Filopaludina sumatrensis dan Corbicula fluminea

Masalah pencemaran sumber air tawar dan kesan ketoksikan logam telah mendapat perhatian di serata negara. Dua spesies organisma air tawar daripada filum moluska Filopaludina sumatrensis dan Corbicula fluminea didedahkan kepada tiga logam terpilih iaitu arsenik (As) kromium (Cr) dan selenium (Se) pada kepekatan berbeza selama 96 jam di dalam makmal terkawal. Kadar kematian dinilai serta kepekatan kematian median (LC50) dan masa kematian median (LT50) dihitung. Nilai LC50 dan LT50 didapati menurun dengan pertambahan masa dan kepekatan pendedahan bagi kedua-dua spesies dan kesemua logam. Keputusan daripada kajian ini memperlihatkan ketoksikan logam As, Cr dan Se semakin meningkat dengan peningkatan kepekatan dan masa pendedahan logam kepada F. sumatrensis dan C. fluminea. Nilai LC50 96 jam As, Cr dan Se bagi F. sumatrensis adalah 4.22, 3.78 dan 45.92 mg/L dan 11.84, 2.23 dan 35.63 mg/L masing-masing bagi C. fluminea. Keputusan menunjukkan Cr adalah logam paling toksik terhadap F. sumatrensis dan C. fluminea. Trend ketoksikan logam bagi kedua-dua moluska ini adalah sama iaitu Cr > As > Se

Hydrological change effects on Sungai Langat Water quality

This study attempts to assess the impact of various types of land use along Sungai Langat and describes hydrological change and water quality variation along this river. This study also determines water quality of Sungai Langat based on low flow dry period Q100,7 using the application of QUAL2K. Dissolved oxygen (DO), pH, temperature and conductivity were measured in situ. Biochemical oxygen demand (BOD5), ammonia nitrogen (NH3-N) and total suspended solid (TSS) were analysed according to the standard methods (APHA). Water quality data was referred to National Water Quality Standards for Malaysia (NWQS) proposed by Malaysian Department of Environment (DOE) to estimate Sungai Langat water quality status. Four important water quality parameters namely DO, BOD5, NH3-N and TSS were simulated with QUAL2K version 2.07 for 83.67 km. As regard to individual parameter, DO classified this river into class III, BOD5 in Class II, NH3-N in Class IV and TSS in Class I. Based on QUAL2K simulation for low flow scenario, the results clearly demonstrates a gradually reduction of DO and BOD5 whereas NH3-N and TSS display opposite. Only NH3-N was found significantly increase which cause low water quality class towards the downstream. Three parameters namely DO, BOD5 and NH3-N show effects of industrial which approximately located at the middle of river stretch. The TSS was contributed to the river system at the upstream and downstream of the river stretch which most likely from sand mining activity which located at Sungai Long, Cheras (near R5) and Sungai Semenyih (R11)

Penggunaan spesies ikan air tawar terpilih sebagai penunjuk biologi pencemaran kromium dan selenium di Malaysia

Tiga spesies ikan air tawar iaitu Rasbora sumatrana (Cyprinidae), Poecilia reticulata (guppy; Poeciliidae) dan Carrasius auratus telah didedahkan kepada kromium (Cr) dan selenium (Se) yang mempunyai julat kepekatan yang berbeza selama 4 hari (96 jam) di dalam makmal. Kadar kematian dicatatkan dan kepekatan kematian ambang (LC50) dan masa kematian ambang (LT50) dihitung. Nilai LC50 kepekatan kematian median (LC50) dan masa kematian median (LT50) didapati berkurang dengan peningkatan kepekatan logam dan masa pendedahan bagi kesemua spesies ikan. Nilai LC50 bagi pendedahan selama 96 jam bagi R. sumatrana, P. reticulata dan C. auratus kajian ini masing-masing bagi Cr adalah 20.91, 19.85, 28.31 mg/L dan bagi Se pula 0.21, 3.03, 0.24 mg/L. Se mempamerkan ketoksikan paling tinggi terhadap tiga spesies ikan air tawar ini apabila mempunyai nilai LC50 96 jam paling rendah jika dibandingkan dengan Cr

Water Quality and Heavy Metal Pollution Status in the Rupat Strait, Indonesia

Rupat strait is located in the north of Dumai, Riau, Indonesia. Rupat strait is the center of shipping, industry, farming, and urban activities. The vast activities are expected to give pressures to Rupat strait ecosystem and its water quality. This study aims to identify the status of Rupat strait water contamination via determination of the degree of heavy metal pollution in Rupat strait water. Samples was taken from 10 location across Rupat strait while the remaining 1 location is the reference location. Sampling was conducted according to SNI 6964.8:2015 in both dry and wet seasons in 2022. The respective physical and chemical parameters were also measured during sampling. Based on the measurement, significant distinction of physical and chemical parameters other than water salinity, TSS, and turbidity (p>0.05) were observed in between wet season and dry season. Rupat strait water was moderately polluted in dry season with Pij 4-8 and mildly polluted in wet season with Pj 3-5. For heavy metal contamination, Rupat strait water was mildly polluted for the whole year with PLI 0.3-0.6. This finding is expected to contribute as references for the surrounding community to maximize the socioeconomic productivity in Rupat strait

The biodiversity of larval chironomidae within limestone springs

EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Flow permanence and macroinvertebrate community diversity within groundwater dominated headwater streams and springs

The response of aquatic macroinvertebrate communities to flow permanence within limestone springs and headwater streams was examined across the English Peak District. At the regional scale, macroinvertebrate communities of perennial and intermittent springs displayed significant differences in the number of taxa, macroinvertebrate community abundance, diversity indices (Shannon and Simpson indices) and the Berger–Parker dominance index at intermediate discharge. However, no significant difference was recorded between intermittent and perennial sites at high discharge or when all sampling occasions were pooled. At the catchment scale, the number of taxa, community abundance and Bray–Curtis similarity coefficients within the River Lathkill differed significantly between intermittent springs and other habitats. At both the regional and catchment scale the macroinvertebrate communities of intermittent springs were characterised by a small number of taxa displaying life cycle adaptations to intermittent aquatic habitats, particularly Trichoptera

Kepelbagaian ikan di Tasik Chini,Pahang,Malaysia

A study on fish diversity and distribution in Lake Chini was undertaken using gill net as capture tools. Eight sampling stations (various habitats) were chosen within the lake system and random sampling was undertaken at selected area. A total 24 fish species were recorded during the sampling, which comprises of 944 individuals. Majority of fish were represented by the Cyprinidae and Thynnichthys thynnoides, Cyclocheilichythys apogon and Notopterus notopterus were the most family dominance species recorded in Lake Chini. Paired t-test analysis demonstrates that there is a significant fish density difference between day time and night time sampling (p = 0.01, α = 0.05) and predators were dominant during night time. Fish diversity and density were high during monsoon season catch, as a result of immigrant fish of Sungai Pahang to Lake Chini through Chini River

A new model for organic contamination assessments using benthic macroinvertebrates as biological indicators

The main goal of this study was to develop a model for organic pollution assessment. Seven sampling sites in six rivers in the Rawang sub-basin, Selangor River, Malaysia, were selected with one reference site. The sampling sites near the fish farm were used to develop the model. SR2 was used for the validation of the developed model. Benthic macroinvertebrates and water sampling were conducted from April 2019 to March 2020. The Principal Components Analysis (PCA) and regression were conducted to select the most representing benthic macroinvertebrates family. Based on the score value (variance coefficient) of each benthic macroinvertebrates family, the cumulative score value of each sampling site was calculated (i.e., 18=6 sampling sites x 3 replicates). The nine benthic macroinvertebrate families (Baetidae, Libellulidae, Protoneuridae Chironomidae, Curbicullidae Hydropchysidae, Tubificidae, Lumbriculiade, and Naididae) were identified using PCA and regression. The cluster analysis and mean confidence intervals were used to classify water quality classes precisely. Finally, three different value scales were produced to represent the level of contamination (i.e., 0.87 as clean status). The newly developed model was validated. The results produced after validation were better than the water quality status from other studies based on the BMWP/BMWP score. This study concludes that the developed model can evaluate river organic contamination successfully