Water Quality Assessment Using Biotic Indices in the Mae Tao Creek, Mae Sot District, Tak Province in Northern Thailand

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1 Water Quality Assessment Using Biotic Indices in the Mae Tao Creek, Mae Sot District, Tak Province in Northern Thailand Witwisitpong Maneechan a,taeng On Prommi a * a) Faculty of Liberal Arts and Science, Kasetsart University, Kamphaeng Saen Campus, Nakhon Pathom Thailand Abstract The biodiversity of aquatic insects were studies for the application of bioindicator of water quality monitoring at five different stations at Mae Tao creek, Mae Sot District, Tak Province in the month of February 2011, 2012 and The Shannon-Wiener index, BMWP THAI Score and ASPT THAI were used to assess water quality. A total of 3,953 aquatic insect taxa from 52 families in 9 orders were identified. The score of BMWP THAI and ASPT THAI were the same that indicated water quality was moderately class. Principal Correspondence Analysis (PCA) indicated that ASPT THAI were related with the air temperature, oxygen dissolved, ph, orthrophosphate and ammonia-nitrogen, whereas, Shannon-Weiner index were related with water temperature, turbidity of water, electrical conductivity, total dissolved solids, alkalinity, sulfate and nitratenitrogen. Keywords: Water quality/ Biotic indices/ Aquatic insects 1. Introduction Monitoring stream ecosystems using aquatic macroinvertebrates has been an effective tool for documenting changes in community health [1]. Some macroinvertebrate indices of stream health have been identified as most useful and efficacious. These include the TBI (Trent Biotic Index) [2], the BMWP (Biological Monitoring Working Party) and the ASPT (Average Score per Taxon) [3] for the UK, the BBI - Belgian Biotic Index [4, 5] for Belgian rivers. Many of these indices have to be adapted when they are used in different regions from where they were developed. One of the most used biotic indices in Thailand is the BMWP (Biological Monitoring Working Party), which is an adaptation of the British BMWP [3]. This score was applied as BMWP THAI by Mustow [6]. The 23 study sites from 4 rivers of the Ping Watershed were sampled; the main Ping River, a highly polluted tributary (Kha Canal), a relatively unpolluted tributary (Taeng River) and an upland stream tributary (Klang River). Samples were collected from 1990 to The BMWP THAI score was therefore modified by removing 15 taxa not present in Thailand and adding 11 taxa which are more suitable to be used in Thailand. The main objective of the present study was to assess water quality of Mae Tao creek using biotic indices (BMWP THAI, ASPT THAI and Shannon-Wiener index) as a tool to evaluate ecosystem health. 2. Methodology 2.1 Study area and sampling station Mae Tao creek is located in Mae Sot District, Tak Province in northern Thailand. The area is surrounded by agriculture activities, community settlements and mining areas. The stream water was primarily to use as a source of portable water supplies to community. Also, it provides a daily source of fish and livelihood to the surrounding community. Five study sites (abbreviated as MT1 to MT5) were located along Mae Tao creek, Mae Sot District, Tak Province, northern Thailand (Figure 1). 2.2 Aquatic insects sampling and identification Field sampling was carried out in the month of February 2011, 2012, and Three replicates of aquatic insect samples were collected from the riparian vegetation, leaf litter, low gradient riffles and pools of each study site using aquatic D-hand net (with a dimension of 30 x 30 cm frame, 250 µm mesh). At each sampling site, a stretch of approximately 50 m was chosen for samples collection. The sampling time at each habitat was 3 min. All samples from randomly chosen sampling points in the reaches were preserved in 95% ethanol in the field and taken back to the laboratory for analysis. In the laboratory, aquatic insects were sorted and identified to the family level using taxonomic keys [7, 8]. All the sorted samples were kept in properly-labelled vials containing 80% ethanol. 2.3 Physicochemical water quality Water quality variables, temperature ( C), dissolved oxygen (DO, mg/l), electrical conductivity (EC, µs/cm), total dissolved solids (TDS, mg/l), and ph were measured in the field using portable meters, such as ph measured by a ph-meter Waterproof Model Testr30, temperature was measured by a handheld thermometer, dissolved oxygen was measured by a HACH Model sension 6 DO meter, total dissolved solids and conductivity were measured by a EURECH CyberScan CON110 conductivity/tds meter. Water samples from each collecting period were stored in polyethylene bottles (500 ml). The ammonia-nitrogen (NH 4 -N), sulfate (SO 4 2- ), orthrophosphate (PO 4 3- ) and nitrate-nitrogen (NO 3 -N) were determined in accordance with the standard method procedures [9]. Alkalinity and turbidity were measured by titration [9] *Corresponding Author: Tel ext. 7610; Fax: address : faastop@ku.ac.th 283

2 Figure 1: Map showing the sampling sites along Mae Tao creek (MT1-MT5), Mae Sot District, Tak Province, northern Thailand. 2.4 Data analyses Mean value and standard deviation of physicochemical water quality parameters in each sampling site was calculated. Analysis of variance (ANOVA) was used to test for statistical differences between the means of the physicochemical water quality parameters of the seven sampling sites. Duncan s Multiple Range Test (DMRT) was also used for multiple comparisons of the means of the physicochemical parameters in order to measure similarities of the sampling points. The indices used in this study were widely known and used in such similar studies elsewhere, including Shannon-Wiener Index, and Biological Monitoring Working Party (BMWP) and Average Score Per Taxa (ASPT) [6]. The BMWP system considers the sensitivity of invertebrates to pollution and families are assigned a score between 1 and 10 accordingly. The BMWP Score is the sum of the values for all families present in the sample. In general, a river with good water quality has a BMWP score of 100 [10]. ASPT was calculated as ASPT = BMWP Score/Number of scoring taxa. A high ASPT was considered indicative of a clean site containing large numbers of high scoring taxa. Principal component analysis (PCA) was applied for collected taxa to assess the impact of human activity on the Mae Tao creek. 3. Results and Discussions 3.1 Physicochemical water quality parameters The mean values and SD of the physicochemical variables are summarized in the Table 1. All sites, except MT5 (2.82 mg/l) were oxygenated ( mg/l) and within the neutral ph (7.73 to 8.61) for all of sampling sites. Mean values of air (26.30 C) and water temperature (24.07 C) were lowest at MT4 while turbidity (5.30 FTU), electrical conductivity ( μs/cm), total dissolved oxygen ( mg/l were higher at MT5. However, some variables such as alkalinity (71.66 mg/l) was higher in MT2, sulfate (35.33 mg/l) was higher in MT4. Dissolved nutrient such as nitratenitrogen was higher in MT1, orthrophosphate was higher in MT4 and MT5, and ammonia-nitrogen was higher in MT2. Air temperature, dissolved oxygen, ph, electrical conductivity, total dissolved oxygen, alkalinity, and sulfate were significantly different (P<0.05) among the sampling sites in the month of February 2011, 2012, and 2013 (Table 1). However, water temperature, turbidity, and dissolved nutrients (ammonia-nitrogen, nitrate-nitrogen, and orthrophosphate) were not significant during three years. 3.2 Diversity of aquatic insects A total of 3953 individuals of aquatic insects were recorded, distributed among 52 families and 9 orders belonging to Trichoptera (1634 individuals, 41%), Ephemeroptera (899 individuals, 23%), Hemiptera (472 individuals, 12%), Odonata (432 individuals, 11%), Diptera (249 individuals, 6%), Coleoptera (237 individuals, 6%), Megaloptera (24 individuals, 1%), Lepidoptera (4 individuals), Plecoptera (2 individuals) (Table 2). Odonata was the most diverse and abundant order which possessed 10 taxa in the Mae Tao creek. However, Odonata showed higher taxa (10 taxa) and less abundance than Trichoptera. Hydropsychidae (Trichoptera) was the most abundant family presented at all sampling sites in the high number of individual (1218) and abundant at MT5. The other key order Hemiptera possessed 9 taxa. Among them, Gerridae and Naucoridae were the most abundant family at MT3 and MT4. Total taxon richness was higher in MT3 and MT4 while was lower in the MT1, MT2, and MT5 (Table 2, Figure 2). The Shannon Weiner index (H ) was higher in MT3 ( ) and MT4 ( ) in all three years while lower at MT1 (1.435) in the year 2013, MT2 (1.947) in the year 2011, and MT (1.208, 1.199) in the years 2011 and 2012 (Figure 2). 284

3 Table 1. Mean values and SD of the physicochemical variable in Mae Tao creek, Mae Sot district, Tak Province in the month of February 2011, 2012 and Means±SD in a row followed by the same letter show no significance difference at p<0.05. Parameter/site MT1 MT2 MT3 MT4 MT5 WT ( C) 26.33±0.43 a 24.86±0.49 a 25.21±1.19 a 24.07±0.99 a 25.73±1.08 a AT ( C) 32.92±2.72 a 32.34±0.98 a 29.55±1.31 ab 26.30±0.61 b 30.16±0.83 a TUR (FTU) 4.66±1.66 a 3.33±1.66 a 3.33±1.20 a 4.33±1.20 a 5.30±3.17 a DO (mg/l) 3.34±0.32 bc 4.59±0.11 a 4.90±0.35 a 4.37±0.30 ab 2.82±0.99 c ph 7.73±0.20 b 8.46±0.12 a 8.61±0.09 a 8.51±0.66 a 8.64±0.39 a EC (µs/cm) ±54.09 b ±5.09 a ±73.75 a ±23.09 a ±94.60 a TDS (mg/l) ±9.12 b ±2.78 a ±23.01 a ±8.94 a ±36.16 a ALK (mg/l) SO 2-4 (mg/l) 51.66±2.84 b 14.66±0.33 b 71.66±2.96 a 26.66±4.24 ab 68.80±3.62 a 34.33±3.92 a 68.86±0.69 a 35.33±4.25 a 69.66±2.18 a 32.33±5.17 a NO 3 -N (mg/l) PO 3-4 (mg/l) 2.13±0.31 a 0.18±0.05 a 1.70±0.10 a 0.12±0.44 a 1.93±0.14 a 0.19±0.10 a 1.96±0.17 a 0.27±0.12 a 1.70±0.15 a 0.27±0.96 a NH 4 -N (mg/l) 0.12±0.07 a 0.96±0.06 a 0.13±0.09 a 0.13±0.10 a 0.15±0.12 a Number of taxa BMWPTHAI ASPTTHAI Species diversity index (H ) MT1_11 MT1_12 MT1_13 MT2_11 MT2_12 MT2_13 MT3_11 MT3_12 MT3_13 MT4_11 MT4_12 MT4_13 MT1511 MT5_12 MT5_13 Figure 2: Taxon richness, BMWP and ASPT, and Shannon index in the month of February 2011, 2012, and 2013 in Mae Tao creek. The Biological Monitoring Working Party (BMWP) score and corresponding Average Score Per Taxa (ASPT) in the Mae Tao creek year 2011 was 158 (6.6), 113 (6.7), 165 (6.6), 178 (6.3), 76 (5.5), respectively. The year 2012 was 130 (7.3), 154 (6.5), 164 (6.5), 157 (6.6), 159 (7.0), respectively. The year 2013 was 41 (5.9), 120 (6.7), 126 (6.7), 117 (6.9), 99 (5.9), respectively. This score is indicative of excellent water quality (Chapman, 1996). Principal Component Analysis (PCA) was used to analyze the correlation between biological indices and water quality variables of all sampling sites during three years (Figure 3). PCA indicated that ASPT THAI were related with the air temperature, oxygen dissolved, ph, orthrophosphate and ammonia-nitrogen, whereas, Shannon-Weiner index were related with water temperature, turbidity of water, electrical conductivity, total dissolved solids, alkalinity, sulfate and nitrate-nitrogen. From this correlation it can be concluded that these indices are appropriate to be used to indicate water quality in Mae Tao creek. 285

4 Table 2. Taxon richness, BMWP and ASPT, and Shannon index in the month of February 2011, 2012, and 2013 in Mae Tao creek. Order Family BMWP THAI Year 2011 Year 2012 Year 2013 MT1 MT2 MT3 MT4 MT5 MT1 MT2 MT3 MT4 MT5 MT1 MT2 MT3 MT4 MT5 Ephemeroptera Baetidae Caenidae Ephemeridae Ephemerellidae Heptageniidae Leptophlebiidae Odonata Aeshnidae 6 1 Calopterygidae Chlorocyphidae Coenagrionidae Corduliidae Euphaeidae Gomphidae Libellulidae Platycnemididae Platystictidae Lepidoptera Pyralidae Hemiptera Aphelocheiridae Gerridae Hydrometridae Mesoveliidae 5 12 Micronectidae Naucoridae Nepidae Notonectidae 5 1 Veliidae Coleoptera Dryopidae 5 2 Dytiscidae Elmidae Gyrinidae Hydrophilidae Psephenidae 8 1 Scirtidae Plecoptera Peltoperidae 10 1 Peridae 10 1 Megaloptera Corydalidae Trichoptera Calamoceratidae Ecnomidae 6 2 Glossosomatidae Hydropsychidae Hydroptilidae 6 1 Leptoceridae Lepidostomatidae Odontoceridae Philopotamidae Diptera Athericidae Chironomidae Dixidae 5 1 Empididae 5 4 Simuliidae Stratiomyidae 4 3 Tipulidae Abundance Number of taxa BMWP THAI ASPT THAI Species diversity index (H )

5 Figure 3: Principal Component Analysis (PCA) between sites, ASPT, Shannon index and environmental gradients of Mae Tao creek. Discussion The physicochemical water quality parameters in the Mae Tao creek (MT1 to MT5) were significantly different, except for water temperature, turbidity and dissolved nutrients (ammonia-nitrogen, nitrate-nitrogen, and orthrophosphate). In a lotic ecosystem, especially streams, biological condition is strongly influenced by water chemistry and habitat quality [11]. Low dissolved oxygen, high nitrate or phosphorous concentrations, and low ph can cause reduced water quality. The list of aquatic insects recorded gave an average BMWP score of 130, which indicates an unpolluted and unimpacted site with clean water. An ASPT score of 6.6 was obtained which has a category designation of excellent water quality [12. The scores for the taxa via the ASPT system are more informative than the BMWP score and relates to the average of the tolerance scores of all the aquatic insects families found in the samples. The water qualities based on the BMWP and ASPT scores for aquatic insects are considered very good mainly due to habitat diversity and lack of pollutants or additional nutrients within the creek. The creek consists of riparian areas and many sections of the creek have varying sediment, gravel, pebbles, boulders, riffles and pools. Many of the taxa associated with the fast flowing well-oxygenated water of riffles in streams were present. Aquatic insect communities of flowing water representative of streams are dominated by the aquatic stages of the insect orders Ephemeroptera, Plecoptera and Trichoptera [13]. Plecoptera are usually found in fast flowing, clean, cold and well oxygenated streams or rivers and an abundance of Ephemeroptera is generally an indication of healthy water. The families Heptageniidae and Baetidae and those species from these families are routinely used as acid sensitive indicators and are known to be vulnerable to both persistent and episodic acidification [13]. Some caddisfly larvae live in a transportable case, which is covered with various materials ranging from algae, plant and/or stones and some live without a case. Most caddisfly larvae have BMWP scores ranging from 5 to 10 and tend not to tolerate low oxygen levels and are found in unpolluted streams. The aquatic insects present in Mae Tao creek consisted mainly of common and widespread species and are typical of those found in clean and well-oxygenated water. The BMWP result is based purely on a raw score with no comparison to a reference site with similar features. Different types of watercourse support different aquatic macroinvertebrate communities and thus different BMWP scores, independent of water quality. The use of benthic macroinvertebrates has become an important tool for monitoring the quality of freshwaters and the species of Ephemeroptera and Plecoptera recorded in these groups are pollution intolerant and indicators that water quality is high. Conclusions Generally, the water quality of Mae Tao creek can be considered as clean, based on the diversity and abundance of aquatic insects and values of biological indices used in this study. The biological indices (Shannon-Weiner index, BMWP THAI and ASPT THAI ) indicated the water quality of Mae Tao creek as rather clean to excellent water quality. Perkin [13] reviewed the performance of eleven diversity indices and concluded that Shannon s index should not be used alone. PCA 287

6 (Principal Correspondence Analysis) indicated that ASPT THAI and Shannon-Wiener index were related with ph, nitrate-nitrogen, electrical conductivity, and orthrophosphate. An updated list of aquatic insects found in Mae Tao creek would be useful in determining the responses of aquatic insects to their surrounding environment. Acknowledgments Financial support for this study was supported by the Thailand Research Fund (MRG ). 4. References [1] Plafkin, J.L., M.T. Barbour, K.D. Porter, S.K. Gross, and R.M. Hughes Rapid Bioassessment Protocols for Use in Streams and Rivers. Benthic Macroinvertebrates and Fish. EPA Office of Water Regulation and Standards, U.S. Environmental Protection Agency, Washington, D.C. [2] Woodiwiss, F.S., The biological system of stream classification used by the Trent river board. Chemical industry, 14: [3] Armitage, P.D., D. Moss, J.T. Wright, M.T. Furse, The performance of the new biological water quality score system based on macroinvertebrates over a wide range of unpolluted running water sites. Water Research, 17: [4] De Pauw N and G. Vanhooren, Method for Biological Quality Assessment of Watercourses in Belgium. Hydrobiologia, 100: [5] Gabriels, W., P.L.M. Goethals and N. De Pauw, Implications of taxonomic modifications and alien species on biological water quality assessment as exemplified by the Belgian Biotic Index method. Hydrobiologia, 542: [6] Mustow, S.E., Biological monitoring of rivers in Thailand: Use and adaptation of the BMWP score. Hydrobiologia, 479: [7] Dudgeon, D., Tropical Asian Stream: Zoobenthos, Ecology and Conservation. Hong Kong University Press. Hong Kong [8] Yule, C.M. and Y.H. Sen, Freshwater invertebrates of the Malaysian region. Aura Productions Sdn. Bhd. Selangor, Malaysia. [9] APHA, Standard methods for the examination of water and wastewater, Section 5210, 18 th ed. Washington DC: American Public Health Association Water Works Association, American Water Environment Federation. [10] Mason, C.F., Biology of Freshwater Pollution, Fourth Edition. Prentice Hall, London. [11] Maddock, I The importance of physical habitat assessment for evaluating river Health. Freshwater Biology 41: [12] Chapman, D., Water Quality assessments: a guide to the use of biota, sediments and water in environmental monitoring. 2nd Edition. UNESCO, London. [13] Perkin, J.L Bioassay evaluation of diversity and community comparison indexes, Research journal of the Water Pollution Control Federation, 55: