Madirda Lake Ecotourism Management Strategy Based on Water Quality Analysis

. Madirda lake is located in Berjo village, Ngargoyoso, Central Java. The utilization of Madirda lake is relatively low although it is continuing to increase every year example for tourism, irrigation and anthropogenic activity. It affects the water quality and also impacts on population. Water quality analysis is needed to find out the quality of water, in this research used three parameters: physical (temperature, TDS and TSS), chemical (DO and pH), and biological (coliform). The result of the research shows that the quality of Madirda lake based on the water Pollution Index (IP) and STORET methods is in compliance with the class I water quality standard, which can be used as a benchmark for drinking water and/or other uses when the same function requires water quality based on water quality standards by the Law Ministry of Environmental No. 22 year 2021. These methods are easy technique and useful for representing the water quality data.


Introduction
Indonesia tourism has experienced various changes in the pattern, form, and activity as well as the encouragement of people to travel, ways of thinking that are able to provide economic growth (increasing income, employment opportunities) and environmentally based tourism or sustainable tourism development and stakeholder have an important role [1] Sustainable tourism development is natural tourism which has aim of enjoying the nature by involving elements of environmental management as well as supporting conservation efforts or in short sustainable tourism development are connected the ecotourism with environmental conservation.
Lake is one of the examples of freshwater ecosystems that have an important part in environmental sustainability and provide facilities to improve the socio-economic life of the community.Madirda Lake is located in the slope of Lawu Mountain in Berjo village, Ngargoyoso, Central Java, altitude of this lake is approximately 600-700 meters above sea level.The development of ecotourism in Madirda Lake can be seen from the activity of the community.For example, this lake only used as a place Hindus to pray and worship, for irrigation and for limited anthropogenic activities and now Madirda Lake is being one of the most popular places to visit.It is because the Madirda Lake developed in all sectors such as facilities (camping, outbound, water sports) and infrastructure that make the community interested in visiting this Madirda Lake.The development of Madirda Lake has positive and negative impacts on the community and environment.
Water quality is one of the impacts of the development of Madirda Lake, water quality analysis is needed to find out the quality of water.This research aims to determine the quality of water in Madirda Lake after experiencing developments and determine the management strategy for Madirda Lake based on water quality analysis.

Material
Water sampling was conducted along the Madirda lake at five stations: inlet, outlet, and center (center I, center II and center III).Purposive random sampling was adopted as recommended by the standard method for water quality analyses.Three (3) parameters are used in this research: physical (temperature, TDS and TSS), chemical (DO and pH) and biological (Coliform).

Methods
This research uses two methods to determine the water quality of Madirda Lake.

Water quality index calculation
According to Abbasi & Sarkar [2], the water quality index is a crucial technique for condensing multi-parameter water analysis into single-digit values.Based on the Law Ministry of Environmental No. 22 year 2021 [3], protection states that the water pollution indices technique (PIj) is one way to calculate the water quality index in Madirda Lake.
To compare Madirda Lake's water quality to the standard, the water pollution index is employed.The liquid pollution index is calculated using this equation: where PIj is the pollution index, Lij is the concentration of water quality standard for parameter i, and Cij is the concentration of parameter i. 3 Result and discussion

Pollution index
The pollution index method assessment in this study is based on water quality standards by the Law Ministry of Environmental No. 22 year 2021 [3].The results of the water quality analysis using the pollution index are presented in the table that shows the water quality in Madirda lake is still in accordance with water quality standards for categories in class I and class II.This means the water quality of Madirda Lake can serve as a benchmark for drinking water and/or other applications where the same level of water quality is needed.When evaluating the water quality of a particular source in relation to time and other contributing variables, the water quality index is crucial [4].The main purposes of the purposes of the water quality index are to: (1) provide numerical comparisons between various waters; (2) allow for the comparison of changes in water quality over time; (3) designate "good" and "bad" quality waters; and (4) offer values that are easier for managers and other non-technical staff to use to characterize water quality [5].

Water quality status of Madirda Lake
STORET method refers to water quality management that is able to portray water quality, offer suggestions for improving water quality, and advise actions to be taken when contaminants cause water quality to decrease [6].The assessment of the quality of water in Madirda lake for class I in the inlet, center I and outlet stations are qualified standards and for center II and center III stations are light polluted and in the average result of Madirda Lake is light polluted in class I with score -2.4 and class II in the inlet, center I, center III, and outlet stations are qualified standard but in center II is lightly polluted and in the average result of Madirda Lake with score -1.6 in class II categorize light polluted according to the government regulation.It is because Madirda Lake has developed in all sectors such as facilities (camping, outbound, water sport) and infrastructure that make the community interested in visiting Madirda lake and increasing the waste.Anthropogenic activity from tourism is the main waste source of pollutants [7].This organic and inorganic waste must be treated before being discharged to Madirda lake.

Conclusion
The results of this study showed that the water quality in Madirda lake is in accordance with water quality standards in class I and class II for index pollution.Meanwhile, the results of the STORET method assessment are categorized as light polluted in scores -2.4 and -1.6.Water quality measurement (index pollution and STORET) is a useful and easy technique used to represent the data on water quality, especially in Madirda Lake, proven to evaluate water changes, to be an effective method to know the waste included in the water and its method assist in interpreting complex scientific data and providing the public and legislators with a clear description of the state of water quality.
The author thanks Prof. Sunarto and Dr. Rhina for helping and Sebelas Maret University for facilitating this research.

Table 1 .
[3]lution IndexMethods for measuring water quality with STORET.Data were analysed using Law Ministry Environmental No. 22 from 2021[3]and STORET.STORET is designed to display the amount of contamination and be calculated for a specific use.The score in Table2is used to determine the category.

Table 2 .
STORET Score and water quality status

Table 3 .
Pollution index in the Madirda Lake

Table 4 .
Pollution index Madirda Lake and water quality status

Table 5 .
STORET method in Madirda Lake