BIOTROPIKA Journal of Tropical Biology
https://biotropika.ub.ac.id/
Vol. 11 | No. 2 | 2023 | DOI: 10.21776/ub.biotropika.2023.011.02.04 ABUNDANCE AND POTENTIAL OF ASTEROIDEA AS BIOINDICATOR OF LEAD
(Pb) IN THE COASTAL ZONE AT BANGKALAN REGENCY, MADURA
Yusfita Kurniawati1), Arnetta Yolanda Maramis1), Istatik Mudloifah1), Dwi Anggorowati Rahayu1)*
ABSTRACT
Asteroidea is a marine invertebrate that has a role as a bioindicator, but the research related to the abundance and potential of Asteroidea as a bioindicator of lead on Madura Island is not to be done. This study aimed to analyse the effect of Pb concentration on Asteroidea population density in Bangkalan Regency. For collecting data, the transect plotting method with a plot measuring 1x1 m2 with 30 plots in the intertidal zone. Seawater sampling was divided into three stations, such as station I-0 meters (edge), station II-50 meters (middle) and station III-100 meters (deep zone), then the seawater samples were tested for lead Pb levels using the AAS method (atomic absorption spectrophotometer).
Data analysis was carried out with quantitative descriptive with Asteroidea composition including diversity index, relative density and dominance index as parameters. The results obtained were sea star species, Cryptasterina sp. and Aquilonastra coronata, with a diversity index value of 0, a relative density of 100% and a dominance index of 1. The results for Pb concentration on Tengket Beach at a depth of 0 meters, 50 meters and 100 are 0.072 ppm; 0.16 ppm; 0.61 ppm and Pantai Modung at 0.5 ppm; 0.83 ppm; 0.82 ppm.
Based on the analysis of the abundance of Asteroidea, the higher the concentration of Pb contained in the waters, the lower the density of Asteroidea. It was concluded that there was no relationship between Pb concentrations in seawater and sea star population density, found a high lead metal yield on the diversity and abundance of sea stars.
Keywords: Asteroidea, bioindicator, density, lead
INTRODUCTION
Indonesia is the largest archipelagic country in the world, with several islands reaching 13 thousand, with strategic locations and a long coastline [1]. Indonesia is a center of biodiversity in the world that has a high biodiversity index.
Indonesian water has many habitat variations of species [2]. One of the seawater that has an abundance and diversity of marine life is the Java Sea.
Madura Island has a water area of 9500 km2. One of the districts of Madura Island is the Bangkalan district. Geographically, Bangkalan Regency is located in the western part of Madura Island at position 112°40'06" - 113°08'44" East Longitude and 6°51'39" - 7°11' 39" South Latitude.
The northern boundary is bounded by the Java Sea, the east, it is bordered by the district of Sampang, and to the south and west it is bordered by the Madura Strait.
Madura is an island that is quite wide and has an abundance of marine life in its waters, especially in Bangkalan Regency. The coastal area of Bangkalan Regency covers the northern and southern areas. These coastal waters have never been done sea star, especially on the northern coast of Tengket and southern areas of Modung Beach.
The coast of Modung and Tengket Beach is rich in marine life, one of which is the phylum
Echinoderms, such as sea stars, sea urchins, sea cucumbers, and others. Echinoderms in Indonesia are found in abundance in coastal areas [3].
Coastal areas are river water that flows from various regions and is mixed with toxic materials from various activities. The number of settlements and fishing activities on the coast of Madura, such as places for manufacturers, painting boats, and tank leaks, as well as the disposal of both households and industrial waste, impacts Madura water with lead (Pb) contamination. Sources of metal pollution mostly come from mining, metal smelting, other industries and domestic waste that uses metals, as well as agricultural materials that use fertilisers that contain metals [3, 4, 5].
Leads inside water have an impact on aquatic organisms, humans, and the surrounding environment. Mass fish death that occurred in 2004 in Jakarta Bay is one of the impacts of high lead heavy metal pollution in the waters [6].
Sea star, a type of the Echinoderm, is one the biotas found in several habitats, such as fine textured sand, seagrass, coral reefs, and sea rocks.
Sea stars also play a role in the food chain cycle inside the marine ecosystem. In conditions, the density of sea star populations can disrupt the ecological balance, one of which is a reduced population of seagrasses which in turn will disturb marine animals that will use seagrass as food
Submitted : September, 8 2022 Accepted : November, 23 2022 Authors affiliation:
1)Department of Biology, Faculty of Science and Technology, State University of Surabaya
Correspondence email:
How to cite:
Kurniawati, Y, Maramis AY, Mudloifah, I, Rahayu DA. 2023. Abundance and potential of asteroidea as bioindicator of lead (Pb) in the coastal zone at Bangkalan Regency, Madura. Biotropika: Journal of Tropical Biology 11 (2): 94-100.
sources, a place to live, and a shelter due to predator attacks.
The efforts to monitor the presence of sea stars in order to manage the sea star population, basic information is needed, especially regarding the structure of sea star community and knowing the relationship between sea star and their habitat characteristics [7]. In addition, sea star has function as detritivores in the intertidal zone. The existence of sea stars is able to associate with coral reefs and beach cleaners from organic materials, so it is one of the bioindicators of a clean sea. Sea stars (Asteroidea) play an important role in the coastal environment. One of them is to eat the carcass and mollusc shells that can pollute the beach, so the sea star is known as marine cleaning animal.
The existence of sea stars is influenced by human activities, the construction of ports on several islands, and the illegal harvesting of sea stars [8]. Hadi [9] stated that the Echinoderms have the ability to determine a suitable location for its place to live. This can lead to Pb contamination and is very influential on the Echinoderms phylum’s habitat, especially sea stars (Asteroidea).
Sea star potential as bioindicators of lead (Pb) in Madura Island study has never been carried out, so this research is a starting point to explore its potential and role in the ecosystem. This study aimed to analyse Pb concentration on Asteroidea population density in Bangkalan Regency.
There is no research related to the biodiversity of sea stars on Madura Island that was used as a bioindicator of heavy metal contamination.
However, previous research was only taken from several small islands in Madura, and any further research on the activity of bioindicators of heavy metal contamination has not been accomplished.
The specific objectives to be achieved in this research are to characterise the biodiversity of sea stars typical of the coast of Madura Island and to know the potential of sea stars as bioindicators of heavy metals. The results obtained can be put to use to improve water conditions by utilising the potential of Asteroidea as a bioindicator of metal pollution.
METHODS
This research was descriptive and exploratory using field observation techniques. This study was carried out for three months, from June to August 2021. The study area was located in the northern and southern waters of Bangkalan Regency, precisely on Tengket Beach in Maneron Village and Modung Beach in Patereman Village (Figure 1). Data was taken in the form of beach conditions, diversity, sea star density, and lead (Pb) concentration in seawater at Tengket Beach and Modung Beach, Bangkalan Regency, Madura.
The data sample was carried out using the transect plotting method with 30 plots measuring 1x1 m2 in the intertidal zone. The transects used three transects with a distance between 10 meters with each plotting. Plot points were observed every 10 meters along the transect line at low tide (Figure 2). The sea stars were found in the plot divided into species and individuals. After that, sea stars were identified by observing their morphological characteristics of aboral and oral parts of the body, body structure, colour shape, and the number of arms, referring to the 1971 Clark and Rowe identification book, web wildsingapore.com, WoRMS web and several related research journals.
Figure 1. Research site map (Source: Google Earth and Google Maps)
Madura Island Research site
area Legend:
= Tengket Beach
= Modung Beach
Figure 2. Sea star sampling method
Seawater samples were divided into three observation stations that were considered representative of Station I, 0 meters depth (edge), Station II, 50 meters (middle) and Station III, 100 meters (deep) (Figure 3). Seawater samples taken from each observation location were put into bottles that had been labelled and then taken to the laboratory to be tested for lead levels of Pb using the atomic absorption spectrophotometer (AAS) method. Pb was analysed at PT. Mitralab Buana Surabaya Laboratory, East Java Province.
Figure 3. Seawater sampling method
To determine the diversity, relative abundance, and dominance of sea stars in Bangkalan Regency, use the following formula:
Diversity index Shannon-Wiener [10]
𝑯′= −∑𝑷𝒊 𝑳𝒏 𝑷𝒊
𝒔
𝒊=𝟏
Information:
H' = index of species diversity
Pi = ni/N
Ni = number of individuals of each species N = total number of individuals
Ln = natural logarithm Dominance index [10]
𝑪 = ∑ (𝒏𝒊 𝑵) ² Information:
C = dominance index
Ni = number of individuals of species N = total individuals of all species
Data on lead (Pb) levels in seawater at each beach and the relationship between lead (Pb) levels in seawater and the abundance of sea star populations were analysed using the Pearson correlation statistical test. Before performing the Pearson correlation test, normality and homogeneity tests were carried out with One-way ANOVA and continued with the Pearson correlation test using SPSS software. The results of the analysis are described by descriptive statistics and presented in the form of tables and figures.
RESULTS AND DISCUSSION
Concentration of lead (Pb). The results of the heavy metal concentration test in seawater in the Bangkalan Regency coastal zone have exceeded the seawater quality standard (>0.005 ppm). Based on seawater quality standards set by Minister of Environment No. 51 of 2004, it stated that the
seawater quality standard for lead content of Pb in waters is 0.005 ppm. Pb concentration at Tengket Beach from the lowest to the highest depth is 0.072 ppm, 0.16 ppm, and 0.61 ppm. Modung Beach has a Pb concentration of 0.5 ppm, 0.83 ppm, and 0.82 ppm. The highest Pb concentration was at Modung Beach at 0.83 ppm at a depth of 50 meters (Central) (Table 1).
Table 1. Lead (Pb) concentration at each depth
Beach
Pb Concentration
(ppm) (< 0.05) Quality Standard
(ppm) 0 m 50 m 100 m
Tengket 0.07 0.16 0.61
0.005 Modung 0.50 0.83 0.82
𝑥̅ 0.29 0.50 0.72
Based on the data obtained, it was known that the Pb concentration in seawater increases along with water depth. This result differed from a study by Eshmat et al. [11], which stated that the farther away from the coast, the lower the Pb level.
However, there are differences in the results at the sampling location at Modung Beach, where at a depth of 50 m, the lead content is greater than at a depth of 100 m.
It could be influenced by various factors, such as water currents that tend to push seawater to the deep side of the waters, which then will deposit lead in the seawater. Eshmat et al. [11] stated that another factor that could cause high concentrations of lead in seawater was the large number of suspended particles that were far from the coastal area.
Figure 4. Heavy metal concentration of lead at each depth
According to Payung et al. [12], complex activities of coastal waters and surrounding areas could be polluted by Pb, which generally comes from domestic waste and various fishery activities, fisherman transportation ports and industrial waste.
The presence of lead pollution in waters, especially
if it exceeds the standard limit, will negatively impact aquatic ecosystems. Reinforced by Darmono (1995), lead (Pb) was a metal included in the pollutant group because it had non-degradable properties and was easily absorbed by living organisms.
According to Eshmat et al. [11], Pb metal will enter the body through the gills, mouth and skin, be absorbed through digestion and accumulate in the liver and kidneys. An increase in the concentration of Pb metal in water was followed by an increase in lead concentrations in the food chain cycle that would cause acute and chronic poisoning and become carcinogenic if consumed by humans [12].
Heavy metal lead that accumulates in the body would be fixed and difficult to be excreted, causing the accumulation of Pb in the body of organisms in the long term [13]. Tertyl-Pb compounds could cause lethal side effects in organisms in the form of acute poisoning in the central nervous system. Pb compounds could have toxic effects on various organ functions in the body even though they were absorbed in small amounts by organisms [14, 15].
Lead is a pollutant found in large quantities in waters and cannot be degraded naturally [16]. Lead has high toxicity to aquatic ecosystems if the amount exceeds a predetermined threshold. Based on the results, this research showed that the average level of Pb in seawater on the coast of Bangkalan Madura Regency had exceeded the quality standard set by PP no.22 of 2021, with seawater quality standards for Pb levels in waters set at 0.005 mg/l.
The high concentration of Pb metal in the water is an indication of the impact of high human activities that can pollute the water. Tengket Beach and Modung Beach are tourist beaches with high human activities, such as beach visitors who litter around the beach and various fishing activities that use fuel in the coastal area, which is basically an estuary zone with more potential to cause water pollution in Bangkalan. These activities pollute the waters of Bangkalan Regency as evidenced by the high lead (Pb) test results.
Diversity and abundance of sea stars in Bangkalan Regency. Cryptasterina sp. and Aquilonastra coronata were the only sea star species found in the study area. The results of this study indicated that two beach areas had a low diversity of sea star species with a diversity index value of 0, a relative abundance index of 100% and a dominance index of 1 for each species (Table 2).
Based on the result, a high value of relative abundance index and dominance index was obtained in both observation areas. A high dominance index category indicated that there was one type of biota that dominated the habitat [17].
0
0.16
0.61 0.5
0.83 0.82
- 0 0 0 0 1 1 1 1 1
0 m 50 m 100 m
Pb Concentration (ppm)
Depth (m) Tengket
Modung
Table 2. Index of species diversity (H'), relative abundance (RA), and dominance index (C) of sea star in Bangkalan Regency
According to Lina & Zulfikar [18], a dominance index that was relatively close to 1 mean that there were one dominant species which was usually followed by a low diversity index and vice versa.
This can be caused by various factors, one of which is the type of substrate that provides suitable food for the species to inhabit. It fits with the statement of Pancawati et al. [19] that substrate is one of the factors that influence the distribution of echinoderms because of the role of the substrate itself as a place to live, providing nutrients for echinoderms as well as protection from predators.
Reinforced by Waay-Juico [20], sea star species richness increases with improving water quality, habitat suitability or habitat diversity and is predicted to decrease with disturbance brought on by humans.
Cryptasterina sp. were found predominately on rocky/coral substrate at Tengket Beach. Byrne et al. [22] stated that the coral rubble habitat on the shore was dominated by Cryptasterina sp. This species was frequently found in groups, with up to 21 individuals in one quadrat and up to 4 individuals found on a single rubble plate. Modung Beach has a type of muddy sand substrate and is rich in food particularly soft coral, sponges and other small invertebrates, which is a suitable habitat for A. coronata.
Tropical Asterinidae are common in intertidal rubble fields and have secretive habits, such as occupying the undersides of boulders or reef infrastructure [21]. The high waves of the northern waters of Madura Island, especially Tengket Beach greatly affect the diversity of biota. Only certain species of sea stars can survive the extreme wave conditions of the north coast of Madura Island [22].
According to Byrne et al. [22], few mobile species, such as Cryptasterina sp. and Aquilonastra coronata, can withstand the harsh physical conditions found in this habitat, with most species seeking refuge during low tides to avoid extreme temperatures and desiccation.
Another factor of low sea star diversity in this study may be related to stress induced by uncontrollable human activity [20], such as industrial pollution and domestic and oil wastes actively destroying the sensitive coastal environment [23]. Retnaningdyah [24] stated that the low diversity index of Shannon-Wiener
Echinoderms in the Spermonde Islands indicated that pollution had occurred in these waters.
The relationship of seawater lead (Pb) concentration with sea stars. The results of the relationship analysis between Pb concentration and population density of sea stars at Tengket Beach using the Pearson correlation statistical test obtained a significance value of 0.235 > 0.05, while at Modung Beach, it was 0.058 > 0.05. So it can be concluded that there is no relationship between the concentration of Pb in seawater and the population density of sea stars on both beaches in Bangkalan Regency. Amriani et al. [14] stated that heavy metal lead could easily dissolve in water and sediment, so the metal would accumulate in the water and sediment on the beach. In addition, heavy metals have the property of being able to easily bind organic matter so that it easily settles together with the waters.
The results showed that there was a decrease in the population of sea stars along with an increase in the concentration of Pb in the waters, both at Tengket Beach and Modung Beach (Figures 5 &
6).
Figure 5. Effect of Pb concentration on sea star population density at Tengket Beach
Figure 6. Effect of Pb concentration on sea star population density at Modung Beach
Beach Species Σni H’ RA C Substrate
Tengket Cryptasterina sp. 64 0 100% 1 Rocky/coral, sandy, Modung Aquilonastra coronata 51 0 100% 1 Muddy, rocky, sandy
Based on Figures 5 and 6 showed that the higher the concentration of Pb contained in the waters, the lower the abundance of sea star populations and vice versa. Retnaningdyah [24] stated that Echinoderms could be an indicator of healthy waters because the interaction between marine biota and their habitat was a dynamic balance. Any changes inside its habitat environment would affect the Echinoderms population, including Asteroids.
There are many factors that can affect the quality of water. There is a mutual influence between the lead concentration and environment around the coastal area, especially in relation to marine life. According to Rochyatun [6], current water patterns affect the concentration of lead because it can cause lead to dissolve from the water surface in all directions, so the lead concentration in water tends to be homogeneous and erratic. In addition, high waves between Java seas that occur in certain months, such as February, July and August, form a long fetch so that seawater mixes in all directions, including various chemical compounds contained in it.
The results showed that the Pb concentration in Tengket Beach, located in the north of Madura, was higher than in Modung Beach in the south of Madura. This may be a result of different wave strengths on the two beaches. Tengket Beach has higher waves than Modung Beach, which will cause Pb to lead easily flowing with water flow into the deep sea. Meanwhile, Modung Beach has calmer waves, which can cause Pb to lead easily accumulate in substrate and biota at the coastal intertidal zone.
The presence of high lead metal test results in Bangkalan Regency reinforces the statement that concentrations can affect the density of biota, especially sea stars. It was further reported by Wahyudi et al. [25] that Bangkalan Regency is near Surabaya city, which plays an important role in economic, tourism, and industrial activities, particularly waste disposal. As a result, it will have an impact on environmental quality. Sea stars are the first organisms with the greatest potential to be affected by lead contamination because sea stars are organisms that have habitats on the bottom of the substrate or the ground [26].
CONCLUSION
Based on the sea star population analysis, the higher the concentration of Pb in the waters, the lower the sea star population will be found. There is no relationship between Pb concentration in seawater and the population density of sea stars on both beaches (non-significant results). The presence of high lead metal test results can affect the diversity and abundance of sea stars. Another
reason is due to some environmental and anthropogenic activities.
ACKNOWLEDGMENT
Thank you to the Directorate General of Higher Education, Ministry of Education, Culture, Research and Technology, for funding this research in the 2021 Student Creativity Program framework.
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