Evaluation of Water Quality Using Physicochemical Parameters and Aquatic Insects Diversity

Abstract

Biomonitoring studies focus on the component of biodiversity, its natural habitats, and species populations which display the ongoing variations in ecosystem and landscape. Physicochemical parameters are important water quality parameters of river water i.e., pH, temperature, turbidity, conductivity, total dissolved solids, total suspended solids, total alkalinity, sulfate, nitrate, heavy metals, and phosphate. This chapter focuses on assessing water quality through Physicochemical Parameters and Aquatic Insects Diversity. The case study investigated the effect of pollutants produced by the human dwelling, agricultural and industrial activities on aquatic invertebrate communities of water of part of Soan River, Pakistan. Four sites were selected based on variation in microhabitat accessibility to examine the pollution in water. Samples were collected from these sites during spring, 2015. Water samples for physio-chemical analysis and macroinvertebrates were collected from all sites. Results showed that conductivity, dissolved oxygen, sodium, and cadmium at all sites were higher than the drinking water quality of WHO standards while potassium, chromium, and manganese were higher in concentration at most downstream sites. However, all other studied parameters were within recommended range of WHO standards. A total of 412 individuals of aquatic insects were collected from the studied sites, belonged to 6 orders and they were the most abundant in April. Total abundance was used to estimate the quality of water at the sites. Most biotic indexes showed that water was of good quality at upstream stations rather than downstream stations, while water quality index (WQI) showed fair water quality at downstream sites. This study showed that aquatic insects could be useful as bioindicators for biomonitoring of water quality along with physiochemical parameters.

1. Introduction

1.1 Physicochemical problems and emergences of biomonitoring

Common methods that rely on chemicals to monitor river pollution are increasingly suitable for monitoring systems as they can detect physical and environmental pressures occurring over time and on multiple scales [1, 2, 3, 4, 5]. However, concepts, and principles of biomonitoring, which are more efficient and effective than traditional methods, have been developed and widely used worldwide to monitor river pollution. Compared to common and uncommon species, bioindicators are more tolerant to environmental change. They are sensitive enough to detect environmental change thanks to their tolerance, but they are also resilient enough to deal with some variability and represent the overall biotic response [6]. However, this new initiative has liberated tropical areas by allowing the model and adaptation of current geologically developed non-tropical species using natural freshwater organisms. These bio-monitoring indicators are often developed for specific regions to respond to regional variables using local biotic collections that reflect regional variability based on sensitivity or biological tolerance. Such variations may affect the strength, performance, and reliability of biomonitoring indicators developed in non-tropical areas (mean temperature between 21 and 30°C and rainfall 100 inches a year) when used in tropical rivers (mean temperatures above 18°C and monsoonal patterns rainfall 79 to 394 inches) [7]. Similarly, modification of non-thermal bio-monitoring indicators used in tropical areas is often captured by incomplete taxonomical resolution and unknown levels of tropical taxa [4]. Abiotic variables or physiochemical samples are problematic in identifying a change or impact in some environmental conditions. For example, contamination can be present in toxic quantities or bio-accumulated, which causes adverse biological deterioration. However, contaminated concentrations may be too small to be detected using this procedure [8]. Consequently, changes in behavioral or pathological responses, population dynamics, environmental pollution, and impacts have been measured using biological rather than physic-chemical indicators by many scientists because of the direct interaction of an organism with the ecosystem [9, 10, 11].

1.2 Importance of biologic index

The use of biological indicators to assess the health of the river ecosystem has become increasingly important because the function of life, biodiversity, population density, human settlement, and the activity of aquatic organisms are affected by all changes in the water ecosystem. River life decisions can be made based on biodiversity and quantity. Many aquatic species such as fish [12, 13], algae [14], plankton [15], and benthic macroinvertebrates [16, 17] are common biologic indicators of water pollution and are used in biotic reliability for the aquatic ecosystem [18, 19, 20, 21]. The types of indicators are those taxes that are known to be more sensitive to certain environmental factors so that changes that occur or in large quantities can directly reflect local change [22]. The usage of biomonitoring techniques in river ecosystems have many advantages compared to physiochemical techniques [23]. Freshwater organisms play an important role in the continuously monitoring water quality and pollutants that enter at different time intervals. In most cases, the disorder occurs during at least one stage (egg, larva, caterpillar, adult) of the invertebrate animal life cycle. If this category is affected by the disruption, changes will be seen in the community structure if sampled over time [24]. Macroinvertebrates are also sensitive to stress; it can be natural or human-based. This change will lead to an impaired community. The aquatic insects show the effect of point and non-point contaminants, physical habitat alteration, and pollutant accumulation over the life cycle [25].

2. Estimation of physiochemical and biological index, a case study of Soan River

2.1 Study site

Sampling sites have been selected that vary in their physiochemical characteristics of the Soan River, Pakistan, at the time of spring 2015. These sites were named A (N 33°43.120, E 073°20.44), B (N 33°37.133, E 073°17.88), C (N 33°33.174, E 073°08.547), and D (N 33°32.906, E073°05.844) which was starts from site A and end at D site as mentioned in [26]. Their positions are shown on the map (Figure 1). The starting point was Simply dam, and the sampling sites were selected thereafter. Photos for Site A (Figure 2), Site B (Figure 3), Site C (Figure 4), and Site D (Figure 5) are presented. In addition, the site descriptions are listed in Table 1. Site A was considered upstream, site B and C considered mid-stream, while all the sites were categorized with respect to major water pollution entry in the river. i.e., site A has no major pollution activities; site B receives poultry farms wastage; site C receives industry pollution wastage without treatment; site D is a dumping point of sewage from Rawalpindi and Islamabad. After that, no major pollution point was spotted.

Figure 1.

Map of study area and location of sampling sites at Soan River, Pakistan.

Figure 2.

Site A.

Figure 3.

Site B.

Figure 4.

Site C.

Figure 5.

Site D.

Study site	Location	Site description
A	Simly Dam	Rich fauna with a greater number of riparian places
B	Aari Syedan	A moderate number of riparian and fast-flowing of water
C	Hummak	No riparian, industrial dumping, and waste product lying on the bank of the river
D	Soan Adae	No riparian, the waste of Rawalpindi and Islamabad was dumped into that point

Table 1.

The geographical position of sampling sites at Soan River.

2.2 Sampling and analysis procedure

From each site, ten water and macroinvertebrates samples were collected. Physical parameters of the area was also recorded. pH, conductivity, total suspended solids (T.D.S), and the water temperature were measured in the field using a portable instrument (HANNA HI 9811-5), and dissolved oxygen (DO) was calculated by using DO-510. The other parameters recorded in Table 2 were determined in the laboratory using a flame (air-acetylene) atomic absorption spectrophotometer (Hitachi, Model Z-5000) and tritremetric methods following standard procedure [27, 28, 29, 30, 31].

Tests	Sampling sites				WHO Standards
	A	B	C	D
pH	7.75(0.05)	7.55(0.15)	7.85(0.05)	8.25(0.15)	6 to 8
Conductivity (μS)	451.5(1.5)	427.5(5.5)	477.0(2.0)	437.0(1.0)	200 to 400
T.D.S (mg/l)	673(2)	677.5(2.50)	682.0(2.0)	653.5(3.5)	500 to 1000
Water Temperature (°C)	26.45 (0.54)	26.04(0.33)	27.13(0.66)	25.21(1.53)
D.O (mg/l)	1.88(0.035)	1.93(0.01)	1.56(0.025)	2.255(0.025)	>4
Chloride (mg/l)	26.50(1.50)	28.5(1.50)	26.50(0.50)	24.5(1.5)	< = 250
Sulfate (mg/l)	32.0(2.0)	35.0(1.00)	27.50(1.50)	32.0(2.00)	< =250
Nitrate (mg/l)	2.06(0.05)	1.81(0.08)	2.20(0.08)	2.25(0.04)	<=10
Calcium (mg/l)	26.85(0.05)	25.6(0.30)	27.60(0.40)	26.60(0.20)	< = 100
Magnesium (mg/l)	18.95(0.15)	18.80(0.20)	19.0(0.10)	18.65(0.15)	< = 50
Total Hardness (mg/l as CaCO3)	312.50(2.50)	322.5(2.50)	317.50(2.5)	302.0(1.0)	100 to 500
Sodium (mg/l)	20.85(0.05)	20.70(0.20)	20.50(0.10)	23.0(2.0)	< = 20
Potassium (mg/l)	8.25(0.15)	7.75(0.15)	10.35(0.25)	11.55(0.15)	< = 10
Aluminum (μg/ml)	0.056(0.003)	0.056(0.002)	0.087(0.0015)	0.012(0.001)	< 0.1–0.2
Cadmium (μg/ml)	0.145(0.025)	0.167(0.002)	0.180(0.01)	0.173(0.002)	< 0.003
Chromium (μg/ml)	0.047(0.002)	0.046(0.002)	0.0530(0.002)	0.064(0.001)	< 0.05
Copper (μg/ml)	0.405(0.015)	0.375(0.015)	0.455(0.017)	0.548(0.018)	< 2
Manganese (μg/ml)	0.394(0.003)	0.374(0.002)	0.565(0.015)	0.589(0.002)	< 0.5

Table 2.

Physio-chemical analysis of water samples collected from Soan River.

A: Simly Dam; B: Aari Syedan; C: Hummak; D: Soan Adae: WHO: World Health Organization; S.E in brackets. Bold indicates that the values didn’t follow the WHO Standards.

2.3 Sampling of aquatic insects

Macroinvertebrates were collected by D-net of 30 cm × 30 cm × 60 cm with 0.5 mm mesh. The net was held vertically right angle to the current. The collection was done by shaking the net at a depth of the river for 1 minute. The collection was done in the morning for 1 week. The collection was done from upstream (A) to downstream (D). For maximizing the complete assemblage of samples, ten replicates from each site were selected every day according to the geographic conditions of the surrounding, i.e., anthropogenic interference and natural causes. After the collecting of water and macroinvertebrates, samples were carried out into 500 ml plastic bottles with enough water, so that samples were not damaged during transportation.

In the laboratory, macroinvertebrates were preserved within a few hours of collection in 90% alcohol. The collection was sorted within a month by RIVPACS (River Invertebrate Prediction and Classification System) standard procedure (Environment Agency, 1997) using taxonomic keys [32]. Small aquatic insects were sorted under a dissecting microscope, whereas large insects were sorted with naked eyes. All samples were then kept in properly labeled vials containing 90% alcohol.

Biotic Index, Biological Monitoring Working Party-Average Score Per Taxon (BMWP-ASPT), The HBI (Hilsenhoff Biotic Index) or Family Biotic Index (FBI), Ephemeroptera, Plecoptera, and Trichoptera (EPT) Index and Water Quality Index were assessed using the data gathered. Small description for each of the indexes are also given as follows.

3. Biotic index

Aquatic insects of the freshwater river and stream ecosystems have frequently been examined to assess the species-habitat relationship concerning the water quality of the habitat [33]. Aquatic insects can indicate the water quality of streams, rivers, and lakes. Once aquatic insects are collected, and after analysis, the data can be compared between different sites by using four standard indices, i.e., Hilsenhoff’s Biotic Index [34], EPT (Ephemeroptera, Plecopterans, and Trichopterans) Index [35], the Benthic Index of Biotic Integrity [25] and Beck’s Biotic Index [36]. The EPT Index stands for Ephemeroptera, Plecopterans, and Trichopterans, three orders of Class Insecta which can easily be sorted, identified, and commonly used as water quality indicators. The EPT index is based upon a high-quality stream ecosystem with a great species richness. Biotic Index shows the quality of the environment by the presence of different organisms present in it, this index is also known as the “Family Biotic Index”. This index is commonly used for river water quality. Biotic Index shows four basic water quality, i.e., (Excellent, Good, Fair, or Poor) measured as 1 to 10. 1 is good, and 10 is poor.

3.1 Biological monitoring working party-average score per taxon (BMWP-ASPT)

Biological Monitoring Working Party-Average Score Per Taxon (BMWP-ASPT) is a biotic index method. That index also estimates the diversity of organisms concerning pollution level. According to different indexes, specimens are placed at various levels from 1-to 10. Plecoptera (rock fly larvae), Ephemeroptera (mayfly larvae), and Crustacea (pole shrimp) are on level 10, Gastropoda (freshwater limpet), Odonata (kini – kini) are at level 8, Trichoptera (caddisfly larvae) at level 7, Odonata (dragonfly larvae), Crustacea (freshwater shrimp) and Bivalvia (shell) at 6 levels, Hemiptera (backswimmer), Diptera (fly larvae), Trichoptera and Coleoptera (water scorpion, diving beetle) at 5, Arachnida (water mite) and Platyhelminthes (flatworm) at four levels, Syrphidae (rattail maggot), Hirudinea (leech), Gamaridae (water pig bug), Gastropoda (snail) and Bivalvia (shell) at 3, Chironomidae (mosquito larvae) at level 2 and Oligochaeta (worm) at level 1. The sequence starts from 10 as excellent and 1 as poorer. Many aquatic species are pollutants intolerant, i.e., levels 10–7 and absent in polluted water bodies. The greater the pollution, the lower the number of insects because few species are tolerant to pollutants, i.e., level 1. The BMWP score equals the sum of the tolerance score of all families in the sample. ASPT was calculated by taking the average number of the tolerance scores of all families of macroinvertebrates which varies from 0 to 10.

3.2 The HBI (Hilsenhoff biotic index) or family biotic index (FBI)

The HBI (Hilsenhoff Biotic Index), also known as the family biotic index (FBI) calculates the level of tolerance in the community of a specific area and the categorization of each taxonomic group by relative abundance. Organisms are grouped with a tolerance number 0–10, and 10 is the most tolerant, while 0 is the most sensitive to organic pollutants [1, 37, 38, 39]. The tolerance values were modified for macroinvertebrates for application in the Modified Family Biotic Index.

The family biotic index (FBI) is calculated as [37].

$$\mathrm{F}\mathrm{B}\mathrm{I}=\Sigma \left({\mathrm{xi}}^{\ast }\mathrm{t}\mathrm{i}\right)/\left(\mathrm{n}\right)\text{,}$$

Where a xi is the number of individuals within a taxon, ti is the tolerance value of a taxon, and n is the total number of organisms in the sample. If the value is between 0.00–3.75, then excellent, 3.76–4.25 very good, 4.26–5.00 good, 5.01–5.75 fair, 5.76–6.50 fairly poor, 6.51–7.25 poor, and 7.26–10.00 very poor.

3.3 Ephemeroptera, Plecoptera, and Trichoptera (EPT) index

EPT index was estimated by summing a total number of individuals group Ephemeroptera (Mayflies), Plecoptera (Stoneflies), and Trichoptera (Caddisflies). If the EPT number is greater than 7 per sample, then it is considered excellent, between 2 and 7 is good, and below 2 is considered poor [40].

4. Water quality index

Water quality was identified based on the water quality index (WQI) [41].

$$\mathrm{W}\mathrm{Q}\mathrm{I}=100-\surd \left({{\mathrm{F}}_1}^2+{{\mathrm{F}}_2}^2+{{\mathrm{F}}_3}^2\right)/1.73$$

Where,

F₁= [Water variables that do not meet objectives/Total number of water variables]*100

F₂= [Number of tests that do not meet objectives/Total number of tests]*100

F₃ = nse/0.01 nse + 0.01

Where,

nse (normalized sum of excursions) = Σⁿ departure/number of tests.

The variables that do not meet objectives are those parameters that exceed the WHO permissible limits. At the same time, the number of tests that do not meet objectives is the number of replicates that do not fall between permissible limits. WQI, the score was scaled between 0 to 100; higher values represent better quality of water, e.g., excellent >80, good 60–80, fair 60–40, and poor <40.

5. Results

The water quality parameters of the upstream section of Soan river tested in this study are summarized in Table 2. The pH was normal in all sites except in site D. Conductivity, D.O, sodium, and cadmium had high values concerning the standards. While, T.D.S, chloride, sulfate, nitrate, calcium, magnesium, total hardness, potassium, aluminum, and copper did not exceed the limit, and fell within the normal range. Potassium, chromium, and manganese show the normal range at sites A & B while surpassing ranges at sites C & D. The water temperature was 25–27°C from upstream to downstream.

A total of 412 individuals of macroinvertebrates were captured, which represents 7 orders. Site A has shown more variety of insects than all the other sites. Total abundance was higher at site C. The variety of insects drops from upstream to downstream stations and only limits to order Diptera (Table 3). In the biotic index, the FBI shows good water quality in upstream stations (sites A & B) while quality decreases fairly in site C and becomes very poor at the last site. The BMWP shows the same trend just like FBI but starts from fair biological quality to very poor biological quality from upstream to downstream. The ASPT represents good water quality at site A and decreases the status to very poor at site D. The EPT only shows good water quality at site A and poor in all remaining sites. In the Physicochemical index, the WQI shows good water quality at sites A & B while fair in sites C & D (Table 4).

Order	Tolerance value	A	B	C	D
Ephemeroptera	5	6.61	0	0	0
Plecoptera	2	1.61	0	0	0
Trichoptera	4	3.22	0	0	0
Hemiptera	5	22.84	45.62	56.8	0
Coleoptera	5	65.72	54.38	35.2	0
Diptera	8	0	0	8	100

Table 3.

Percent composition (%) of aquatic insects in four different stations of Soan River, Pakistan.

Study site	Biotic index								Physicochemical index
	FBI		BMWP		ASPT		EPT index		WQI
	Value	Class	Value	Class	Value	Class	Value	Class	Value	Class
A	4.6	Good	54	Fair biological quality	6	Good	7	Good	71.28	Good
B	4.49	Good	30	Poor biological quality	5	Fair	0	Poor	68.36	Good
C	5.23	Fairly	17	Poor biological quality	4.25	Poor	0	Poor	59.82	Fair
D	10	Very poor	0	Very poor biological quality	0	Very poor	0	Poor	55.57	Fair

Table 4.

The water quality of the Soan River is based on biological indices and water quality index.

Notes: FBI = Family Biotic Index; BMWP = Biological Monitoring Work Party; ASPT = Average Score Per Taxon; EPT = Ephemeroptera, Plecoptera and Trichoptera; Water Quality Index = WQI.

6. Discussion

In this study, water quality was examined using chemical, physical, and biomonitoring methods. In chemical analysis, different parameters were tested, such as magnesium, chromium, aluminum, copper, cadmium, dissolved oxygen (DO), nitrogen (N), and phosphorous (P) [42]. Physical parameters include pH, total suspended solids (T.D.S), conductivity, chloride, sulfate, nitrate, calcium, total hardness, sodium, and potassium. In bio-monitoring FBI, EPT, ASPT, and BMWP were calculated to determine water quality.

The concentration of metals was almost normal but some of them were high such as cadmium, sodium, potassium, and chromium. The pH values were low at the start and exceeded in site D. This shows that Organic influx wastage in the monsoon season may lower the water pH at that site D. The pH affects the biochemical process as well. It also indicates water quality and the extent of pollution in the watershed [42]. Among the different heavy metals, Cd shows a higher level of concentration which did not support any life or for drinking purposes (3 μg L⁻¹) [43]. Cd is the typical anthropogenic metal affected by human activities [44] and showed enrichment. It is shown that Cd is associated to a greater extent with colloidal materials in surface runoff which can easily be transported into river flow [45]. Metals, such as Cu, Zn, and Pb, have a high affinity to human substances present in organic matter. The presence and quality of organic matter differentially influence the binding of metals within the sediments, reducing the adsorption of Cd and Co and increasing the adsorption of Zn [46]. Discharge of industrial, sewage, and poultry waste largely untreated forms may cause the elevation of metals in the water [47, 48, 49]. The water quality shows poor quality at those sites which drain sewage of the twin cities, while at downstream sites, the natural process shows some recovery from stress conditions due to the huge amount of sewage waste from the urban [50]. Activities of humans can change the smallest change in the ecosystem, especially downstream of the Soan River. The poor quality of water at downstream rather than upstream stations can result from several human activities, sewage, nutrient, sedimentation, and agriculture pesticides residue run-off. Wahizatul et al. [51] also studied in the Sekayu stream and found that agricultural and recreational activities were directly related to the destruction of aquatic species diversity in the Sekayu recreational forest. The higher organism abundance at site A is related to greater availability of coverage of riparian vegetation, which offers them a great supply of hiding places, allochthonous material, and food availability. Roque et al. [52] pointed out that the area with greater vegetation coverage has greater taxonomic richness. Although, at sites C and D, low diversity is found which could be related to the loss of riverbank vegetation and replaced by waste material, shrubby, exotic vegetation, and a lower quantity of heterogeneous substrate. This phenomenon was noted by [53]. Adamu Mustapha and Geidam [54] reported that high nutrients loading at urban sites are due to discharge of sewage wastewater of Rawalpindi and Islamabad.

Chironomidae (Diptera) were most abundant at downstream of the Soan River. They show no variation and are found in all stations. Yule and Sen [32] reported that in Malysia, Chironomidae is probably the most abundant and diverse group of all macroinvertebrate’s streams. The sandy or muddy areas and slow-flowing or standing streams with a high number of sediment particles are the best areas where Chironomidae can excel [32, 55]. Due to heavy rainfall, the flood affected the macroinvertebrates from all the sites. Thus, effect seasonal taxa richness. The member of Chironomidae was most affected by the flood. The mayflies (Ephemeroptera) and true bug (Hemiptera) did not show any response to heavy rainfall because they are morphologically better adapted, attachment abilities to stones, mobility in water and behavioral pattern during mating. Holomuzki and Biggs [56] studied the behavioral pattern in response to the flood. The fluctuation of water level in the winter season remained very low. This is the major stressing factor for littoral organisms. Nairn et al. and Gopal [57, 58] also recorded a similar finding on littoral destruction. The macroinvertebrate density in the Soan River was found to be the lowest when the monsoon season starts and increases when the monsoon stops. Wallace et al. and Jakob et al. [59, 60] pointed out that monsoon floods decrease macroinvertebrates’ density, especially Chironomid species known as two-winged flies. EPT was not found abundantly in any collection points, especially downstream. EPT members are known to be the most sensitive insects to environmental stress. Therefore, the presence of EPT upstream indicates a relatively clean environment [61, 62]. Therefore, the EPT can be used for potential bioindicator purposes. The BMWP index shows poor results for all the sampling sites, but some sites show fair biological quality at site A as well as ASPT [62]. Therefore, the presence and absence of macroinvertebrates along with water physicochemical analysis at upstream and downstream shows the influence of anthropogenic and natural influences. This suggests that aquatic insects can be used to access the water management in Pakistan as the role of potential bio-indicators.

7. Conclusion

The biological and WQI index shows water quality was good at upstream rather than at downstream stations. The biotic index shows a clear variation throughout the sites. While the physicochemical index shows the same trend at site D and it shows fair water quality despite the biotic index is Poor. The biotic index is detailed and efficient while the individual can gather information on the spot, but physicochemical parameters are costly, laboratory intensive, and time-consuming. These two indexes can be used alternatively concerning the situation.

Acknowledgments

This study was sponsored by the World Wildlife Fund (WWF) Pakistan through the young Ecologist Scholarship. Special funds for a multipurpose water analysis kit were provided by the University of the Punjab, Lahore. The authors are extremely thankful to both organizations.