Bengawan Solo Research Articles

Sintesis Metal-Doped Carbon Nitride Nanosheets sebagai Pengurai Limbah Pewarna secara Fotokatalisis

<p><em>Batik dye waste pollutes the Bengawan Solo River in high levels. One of the effective efforts to overcome pollution in the aquatic environment is through a degradation process using photocatalysts with UV-rays. In this research, carbon nitride nanosheets as photocatalyst with zirconium and cobalt doping was used. The addition of doping on g-C3N4 nanosheets was able to improve the photocatalytic performance. The purpose of this study was to determine the effect of various types of doping on the photoremediation performance of carbon nitride nanosheets. Synthesize Co-doped g-C3N4 nanosheets and Zr-doped g-C3N4 nanosheets was carried out by synthesizing pure g-C3N4 nanosheets using melamine and ammonium sulfate that calcined at 600°C. Afterwards, the mixture was impregnated by Zr and Co-doped using a vacuum evaporator. The effectiveness of the photocatalyst to degrading rhodamine-B was analyzed using X-Ray Diffraction (XRD) and UV-Visible Spectrophotometer. The result shows that photodegradation performance of Co and Zr-doped g-C3N4 nanosheets has increased. Based on the absorbance data of photocatalysts, the Zr-doped g-C3N4 nanosheets photocatalyst give the most optimal results in degrading rhodamine-B with the final rhodamine-B concentration close to zero.</em></p>

PENGEMBANGAN INFRASTRUKTUR DIGITALISASI DESA MENDUKUNG DESA WISATA DAN TEKNOLOGI SOLAR CELL DESA

Agricultural infrastructure is the key in the main business field to support the economic growth of the village. The geographical area of Banjarsari Village is a lowland inundated with swamp water adjacent to the Bengawan Solo river, the border of the Jombang Regency area with Nganjuk Regency, a population of 49,959 people, rice fields with an area of 241.79 ha, agricultural production in the form of rice paddy fields and fields with a harvest area of 3,471.1 tons, corn production of 320.1 tons, plantation production of 2,436.09 tons. This shows the strength of Banjarsari Village in Agriculture and Animal Husbandry, very important supported by infrastructure and access to agricultural technology, modern agricultural irrigation infrastructure, especially the use of renewable energy technology that has zero agricultural electrification costs The purpose of implementing this KKN is to lead rural communities to a more prosperous life and help improve the social conditions of rural communities and make villages better known in terms of tourism and village MSMEs. The method in implementing this KKN is by interviewing and field observation methods.

STORAGE AND COLLECTION RIVER DEBRIS PLANNING IN TANGGUL RIVER SURAKARTA CITY, INDONESIA AS SOURCE OF WASTE MANAGEMENT USING THE MULTI-CRITERIA DECISION-MAKING METHOD

The Tanggul River in Surakarta City is a tributary that empties into the Bengawan Solo River. Domestic activities located on river borders can pollute with the waste generation. Therefore, managing waste sources such as storage and collection is crucial in waste management. This study aims to analyze waste management from river debris storage and collection around the study site. The technique used in this research is direct observation of the study area and performing a decision analysis for alternative processing. Decision support system has one model, namely Multi-Criteria Decision Making for environmental development. The activities for collecting and sorting river debris in the Tanggul River are not yet available. The existing river debros collection used a 7 cm diameter net that has been installed at the sluice gate of the Tanggul River. Considering aspects or criteria in implementing accommodation activities needs to be carried out before determining the best alternative. Therefore, several measures need to be considered in determining the container based on SNI 19-2454-2002 concerning Operational Procedures for Urban Waste Management and Minister of Public Works Regulation Number 3 of 2013. The collection activity in alternative 1 uses the Brute Boom system: Heavy Duty Containment Boom equipped with a galvanized weir mesh net attached under the boom. The collection activity in alternative 2 uses a floating cube. The floating cube is a cube-shaped Waste holder that can float in the river to effectively hold waste floating on the surface of the river body. It is imperative to prevent river pollution from activities by providing infrastructure for storing and collecting waste. However, it does not have a more significant impact, such as the Tanggul River to the Bengawan Solo River in Surakarta City.

“BANJIR DAN BANTUAN DI SURAKARTA” FILANTROPI DALAM BANJIR SOLO TAHUN 1966

ABSTRACT This research discussed aboute the philanthropic practices that occurred in the Solo flood in 1966. The city of Solo and the surrounding area is an area that is often subject to flooding. This happens because Solo City is one of the areas crossed by the Bengawan Solo River, where Bengawan Solo is the longest river in Java Island. If at any time there is a significant increase in rainfall and for a long time, the worst risk caused is the occurrence of a flood disaster. One of the major floods that hit Solo City and the surrounding area was the flash flood that occurred in 1966. The incident hit six inner districts and caused considerable losses. The problem studied this time is how the philanthropic practices of the Indonesian people remain intertwined in the midst of unstable political conditions, because 1966 was a fairly crucial period. To conduct this research, the author used the historical research method. This method includes the selection of titles, data collection, criticism or selection and filtering of data, interpretation or interpretation of the data that has been obtained, and the last step is historiography or the stage of writing history. In addition to using historical research methods, the author also uses the concept of social roles as a theoretical basis in carrying out the research. The concept was chosen by the author because it is able to help the author in seeing how the role of each individual and group in the recovery of the Solo City Area and its surroundings after the flash flood disaster. The results of this reseach is explain how the flood disaster that hit the Solo region and its surroundings in 1966 could move a sense of humanity and empathy among the Indonesian people in the midst of unstable political conditions. Until the people of Solo City and also the surrounding areas who are victims of the disaster can bounce back from the slump caused by the flood disaster. The participation of the Indonesian people as a reaction to the flood event that hit Solo and its surroundings was able to restore the state of Solo City and the surrounding area as before. Keywords: Bengawan Solo, flood, philanthropy

Study of Javanese philosophical values in Kliwonan batik from Sragen District, Central Java, Indonesia

Abstract. Puryanti, Hermanu J, Wahyuni S. 2019. Study of Javanese philosophical values ??in Kliwonan batik from Sragen District, Central Java, Indonesia. Asian J Ethnobiol 2: 51-69. The research objectives are to describe: (i) The background of Kliwonan batik in Sragen District. (ii) The history of creating the Kliwonan batik motif in Sragen District. (iii) Javanese philosophical values ??contained in Kliwonan batik in Sragen District. This research was conducted in Kliwonan Village, Masaran Sub-district, Sragen District, Central Java, Indonesia. This study used the descriptive qualitative method. The sample used is purposive sampling. Meanwhile, interview, observation, and document analysis used the data collection technique. The validity of the data used is a triangulation technique, namely triangulation of data sources and triangulation of methods. The data analysis technique in this study used a qualitative analysis model and interactive analysis. Based on the results of this study, conclusions can be drawn: (i) Kliwonan batik craft in Kliwonan Village is related to Ki Ageng Butuh. For the services of Ki Ageng Butuh, finally, the village of Kuyang (Koni Kliwonan) and the village of Butuh (now the village of Gedongan), which are separated by the Bangawan Solo river, are used as bounty villages, so in this village, the palace culture also developed, namely batik, starting from the Abdi dalem kriya who become a batik worker in the palace. These skills were then developed in the village of Butuh-Kuyang and passed down from generation to generation in the Butuh and Kuyang areas which the Bengawan Solo River only limits. (ii) The process of creating batik motifs includes several aspects until the creation of a motif: function, material, form, technique or process, and aesthetics. All of these aspects start with an idea. In traditional written batik in Kliwonan, the idea of ??making motifs is influenced by external factors in the form of cultural factors. Traditional batik motifs are designed based on traditions passed down from generation to generation as a form of cultural preservation and to fulfill requests related to traditional needs. So in traditional batik motifs and visual beauty, there is also meaning. The internal aspects of making traditional batik motifs and new creations are the same, but different creative ideas affect the overall visual form. (iii) Kliwonan batik is part of Surakarta batik, so the motifs in batik are also full of Javanese philosophical values. The traditional written batik motifs in Kliwonan Village consist of: (a) The semen motif is a classic batik of Semen Surakarta, which is full of symbolism that shows the worship of fertility and the order of the universe, the aims, and objectives of the semen classic batik are manifested and contained in the names of batik the classics themselves, such as semen rama, semen cuwiri, and semen gendhong; (b) the Parang and Lereng motifs are traditional batik motifs with a line pattern, the name parang is closely related to the existence of Ingkang sinuhun Panembahan Senopati, the founder of the Mataram Kingdom, after the move of the center of government Java from Demak to Mataram, which is the place of “teteki” or the meditation of the first Mataram king who inspired the emergence of batik lerengan or parang as a feature of Mataram ageman which is different from the previous batik; (c) Ceplokan motif means a piece which has the meaning of “power,” the interpretation of symbolism. This is inspired by the concept of power in the four main ornaments and one point in the middle of the ceplok motif, which describes the king's power over his people and the people who always surround and protect him.

Distribution of Water Pollution SubBengawan Solo Upstream Watershed on Central Java in 2020

The Bengawan Solo watershed is included in the 15 priority watersheds that must be restored because it is one of the 108 critical watersheds in Indonesia. It is indicated that the Bengawan Solo Hulu sub-watershed is experiencing pollution and water quality degradation due to the population growth rate and various community activities around the watershed area. This research was conducted to study pollution and water quality using a spatial approach in the Upper Solo Bengawan sub-watershed in the Central Java region. The research was conducted using the Pollution Index method and Geographically Weighted Regression (GWR) modeling using BOD, COD, TSS, TDS, DO and Phosphate parameters. The results of the Pollution Index carried out show that 5 sample points are included in the category of light pollution quality and 8 sample points are moderately polluted. The lowest pollution index value is 2. 87 at point 3 of the Upper Samin River area, Karanganyar Regency. The highest pollution index value is 7.5 at point 9 in the Lower Premulung River area, Surakarta City. The results of GWR on the dependent variable BOD show that the DO variable has the most significant effect. In the dependent variable COD, the BOD variable has the most significant effect. The TDS and Phosphate variables have the most significant effect on each dependent variable and the DO dependent variable shows that the BOD variable has the most significant effect compared to other variables. In the dependent variable COD, the BOD variable has the most significant effect. The TDS and Phosphate variables have the most significant effect on each dependent variable and the DO dependent variable shows that the BOD variable has the most significant effect compared to other variables. In the dependent variable COD, the BOD variable has the most significant effect. The TDS and Phosphate variables have the most significant effect on each dependent variable and the DO dependent variable shows that the BOD variable has the most significant effect compared to other variables.

Morphological Analysis of Sili (Macrognathus sp.) in Some Regencies in East Java Province

Sili (Macrognathus sp.) is one of freshwater fishes that has high economic value in Asia, since it is beneficial as a consumable fish and an ornamental fish. The economic potential of Sili triggers overfishing, especially in East Java. Domestication is a method to preserve Sili in East Java, preceded by identifying potential species of Macrognathus sp. from the natural catchment. This study aims to characterize the morphological differences of Macrognathus sp in several regencies in East Java based on morphological and morphometric phenotypes. Samples were collected at five different locations, specifically: Tulungagung (Boyolangu Watersheds), Kediri (Brantas Watersheds), Mojokerto (Brantas Watersheds), Lamongan (Bengawan Solo Watersheds), and Malang (Karangkates Reservoir). The main parameters observed were morphology and morphometry. The morphological analysis used identification guidelines, while morphometric data were obtained through 14 parameters measurement then analyzed using one-way Anova test on SPSS 25 software. Based on the morphological and morphometric analysis, it is known that the species of Sili in some regencies in East Java are Macrognathus tapirus and Macrognathus aculeatus. The results showed that samples from Tuban and Kediri are Macrognathus tapirus. Furthermore, the samples collected from Mojokerto, Lamongan, and Malang are Macrognathus aculeatus. One-way Anova test showed Sili from the five locations were significantly different based on the result value of p<0.05.

Central Java regional geochemistry: influence of environmental geology and mineral occurrences

Stream sediments geochemical surveys were undertaken in Central Java, Indonesia as a part of the Geological Agency’s geochemical mapping project with support from several universities. A total of 1583 stream sediment samples were collected from Central Java and analyzed using X-Ray Fluoresces for 29 elements. Geochemical maps were processed by the GIS software. Based on the overlay between geological and geochemical maps, there are several elemental anomalies, for example, the ultramafic formation from Kebumen showing distinctive Chromium (Cr), Cobalt (Co), and Magnesium (Mg) anomalies. Meanwhile, the potassic igneous rocks from Muria Mountain have Cerium (Ce), Lanthanum (La), and Zirconium (Zr) anomalies. Elemental anomalies related to mineral resources and mining areas such as Arsenic (As), Copper (Cu), and Lead (Pb) are found in Trenggalek, Pacitan, and Kebumen; while Barium (Ba), Iron (Fe), and Manganese (Mn) are scattered along the southern coast of Central Java. Anthropogenic elements (Chlorine (Cl), Ce, and As) spread along the north coast of Central Java probably because of pollution by industrial, farming, and urban areas. Heavy metals pollutions that were identified previously in the Bengawan Solo River flow can be seen on this geochemical map which can convincingly delineate elements anomalies due to geological and environmental conditions.

Floating Rice Cultivation: a Solution to Reduce Crop Failure in Flood-Prone Areas

Bojonegoro is a regency in Indonesia located downstream of the Bengawan Solo River, a flood-prone area that caused crop damage and failure. The farmers need appropriate technology as an adaptation to reduce the loss of crop failure. Therefore, this study aims to determine the potential of floating rice cultivation as a solution for reducing crop failure. The experiment was arranged in Randomized Complete Block Design with two factors, namely planting media (soil:organic fertilizer (1:1) (M1); soil:rice husk (1:1) (M2); soil:organic fertilizer:rice husk (1:1:1) (M3)), and plant spacing (15 cm x 15 cm (J1); 20 cm x 20 cm (J2); 25 cm x 25 cm (J3)). Each unit treatment was replicated 3 times. The results showed M2J3 gave the best outcome on plant height of 94.3 cm, the tillers number of 21.7, and produced the highest rice yield of 14.16 tons ha-1. This treatment provides optimal soil conditions, high cation exchange capacity (CEC) of 26.6 cmol (+) kg-1, phosphorus availability (Av-P) 48.5 ppm, and potassium availability 0.9 ppm. The planting media compositions significantly affected soil cation exchange capacity, soil phosphorus availability, plant height, tillers number, and rice yield. The yield on floating rice cultivation was approximately similar when compared to the local farmer's fields. Floating rice cultivation can be used as a solution to reduce crop failure in flood-prone areas in Bojonegoro.

Kajian Kelayakan Kawasan Arkeologi Lembah Bengawan Solo Purba di Pracimantoro sebagai Wisata Edukasi di Jawa Tengah

&lt;pre&gt;&lt;em&gt;Pracimantoro has various tourism potentials, one of which is the Gunung Sewu area which is recognized by UNESCO as a global geopark. In one part of the geopark, there lies Bengawan Solo Purba valley which is the ancient Bengawan Solo river flow. Considering the significance of Bengawan Solo to the life of the Javanese people, and its archaeological values, this valley has the potential to be developed into a tourism object. This paper focuses on the feasibility study of the development of this valley into a tourist destination. The method used in this study is SWOT analysis to discuss the strengths, weaknesses, opportunities, and threats of Bengawan Solo Purba Valley. The results of the study show that it is possible to develop this area as a tourist destination but for educational tourism purposes focusing on archaeology.&lt;/em&gt;&lt;em&gt;&lt;/em&gt;&lt;/pre&gt;

Temporal analysis of total suspended solids (TSS) at Ujung Pangkah Beach, Gresik, from 2016 - 2020 using aqua MODIS image data

Total suspended solids (TSS) is a parameter widely used to detect pollution on the coast, especially in areas that have a sloping coastal structure where currents and waves parallel to the coast will accumulate these solids to form sedimentation gradually. This study aims to map the distribution of TSS on the coast of Ujung Pangkah Gresik where at the end of this coast there is a flow from the Bengawan Solo river. The method in this study implements remote sensing technology to collect Aqua MODIS satellite image data of from 2016 to 2020. Based on calculation results, the wavelength band 1 (660 nanometers) of the Aqua MODIS image is the best wavelength by looking at the R correlation value generated of 0.573, so it can be concluded that the Aqua MODIS satellite imagery with a resolution of 250 - 500 meters can still be used to create a mathematical model for mapping the TSS distribution on the coast. In terms of forecasting for 5 years, the reflectance value generated from the image does not give significant results, because this satellite image is very influenced by the weather, so it is very difficult to get a cloud-free image in the same month every year to extract the reflectance value.

KYAI RAJAMALA BOAT’ CANTHIK IN COUTURE BATIK PATTERN

The Historically, the Javanese palaces relied on boats for transportation, like the Kyai Rajamala boat used by the Surakarta palace. At the time, Paku Buwana IV used the boat to cross the Bengawan Solo river. Kyai Rajamala boat’s canthik is a decorative element on the end bow of the Surakarta palace's boat. Apart from being a decorative element on the boat's end bow, the Kyai Rajamala boat’s canthik is also an heirloom used to ward off bad luck. Because the Kyai Rajamala boat’s canthik has a high value for life, it is critical to communicate the Kyai Rajamala boat’s canthik through easily accepted media. One medium that can convey the beauty of the Kyai Rajamala boat’s canthik is the batik textile art, which can be used to meet basic human needs. Clothing is not only a means of covering the body; it can also be used to convey messages. The Kyai Rajamala boat’s canthik was reinterpreted and dyed with remasol into handmade batik.

Study Of Flood Disaster Risk Delta In Bojonegoro Regency

A disaster is an unexpected and often sudden event that causes destruction, serious damage, and human suffering. According to the Law of the Republic of Indonesia Number 24 of 2007 concerning Disaster Management, disasters are caused by natural factors and/or non-natural and human factors so that disasters can result in loss of life, environmental damage, loss of property, and psychological impacts. Bojonegoro Regency which has the widest area crossed by the Bengawan Solo river and 24,753 hectares of its area is a watershed so that almost every year Bojonegoro Regency is flooded when the Bengawan Solo river overflows. Floods in Bojonegoro Regency almost occur every year. Where the flood that occurred in Bojonegoro Regency was caused by the overflow of the Bengawan Solo river. As much as 63% of the total population of Bojonegoro Regency is exposed or at risk of flooding in 2012 to 2020. This study is to determine the Delta (Δ) risk of flood-prone areas in Bojonegoro Regency based on trends in land use change with a multitemporal perspective in Bojonegoro Regency. This study uses the latest methods, especially in terms of spatial modeling, namely TIN and Raster databases. The first step is to predict the trend of land use in Bojonegoro Regency. Which is then continued to identify flood hazards and land use vulnerabilities. Flood disaster-prone areas each year are predicted based on the previous stages using the Analytic hierarchy process which then produces disaster risk in each prediction year. The last step is to calculate the amount of change or Delta (∆) of Flood Disaster Risk in Bojonegoro Regency. The results of this study are Delta (∆) Low Flood Disaster Risk: experienced a change of -1.62% or decreased by 49.66 Ha from 2020 to 2040. Delta (∆) Moderate Flood Disaster Risk: experienced a change of 2.85% or experienced an increase of 17.67 Ha from 2020 to 2040. Delta (∆) High Flood Risk: experienced a change of 23.96% or an increase of 31.99 Ha from 2020 to 2040.

Situs Perahu Kuno dan Perahu Besi di Bojonegoro

The issuance of the Canggu inscription illustrates that Bojonegoro was one of the areas through which the Bengawan Solo flow passed, which played an important role in trading activities. So don't be surprised if you find many relics such as coins, pottery, boats and others. The boats that have been found at the bottom of the Bengawan Solo river in Bojonegoro are an ancient boat in Padang Village, Trucuk District which was found in 2005 and an iron boat in Ngraho Village, Gayam District which was lifted to the mainland in 2013. briefly about the existence of Bengawan Solo and the crossing villages as well as explaining the ancient Trucuk boat and the Ngraho iron boat from the initial discovery conditions to the present day. It is hoped that readers will be able to know the historical evidence of the glory of Bengawan Solo, namely by knowing and understanding the findings of ancient boats in Bojonegoro which have historical value. The method used in this study is a historical research method which is divided into heuristics, verification, interpretation and historiography.

Keabsahan Peraturan Walikota Surakarta No. 12 A Tahun 2017 tentang Petunjuk Teknis Pemberian Bantuan Sosial Pengganti Bangunan di Atas Tanah Negara pada Bantaran/ Sempadan Sungai Bengawan Solo dan Anak- Anak Sungainya

&lt;table width="601" border="0" cellspacing="0" cellpadding="0"&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td valign="top" width="393"&gt;&lt;p&gt;&lt;em&gt;In order to fulfill human rights to obtain certainty of proper and valid residence in accordance with Article 28H of the Indonesian State Constitution of 1945, especially to Structuring Affected Residents due to the Slum Relocation Policy in Bantaran Kali Anyar, Nusukan Village conducted by the Surakarta City Government. Surakarta Mayor Regulation No.12A of 2017 aims to create the Bengawan Solo Riverbank area and its tributaries, one of which is Kali Anyar as a flood control area, and secure residents from social possibilities, as well as clean up buildings above it by providing social assistance to Structuring Affected Residents. This research is normative research with a statutory approach and a conceptual approach. The results of this study concluded that Surakarta Mayor Regulation No.12A of 2017 is a policy regulation for providing social assistance that is the guidelines of the Surakarta City Government to Affected Residents in Bantaran Kali Anyar. Surakarta Mayor Regulation No.12A of 2017 is in accordance with legal principles, not contrary to the laws and regulations, in accordance with the AAUPB.&lt;/em&gt;&lt;em&gt;&lt;/em&gt;&lt;/p&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;

PEMULIHAN EKONOMI MASYARAKAT PASCA PANDEMI MELALUI PENGEMBANGAN WADUK TIRTO AGUNG SEBAGAI WISATA ALAM YANG MENARIK DI DESA PRANGI KECAMATAN PADANGAN KABUPATEN BOJONEGORO

Prangi Village is a village located in the Padangan District, Bojonegoro Regency, East Java, more precisely located on the coast of the Bengawan Solo River which is directly adjacent to the province of Central Java. The population of Prangi Village above, most of whom work as farm laborers, and only a few who actually own agricultural fields, make the economic situation of the residents classified as pre-prosperous or can be said to be middle to lower level residents. This unstable economic situation makes people's incomes become unstable. Especially after the covid 19 pandemic. Therefore, it is necessary to empower their own resources through the development of the Tirto Agung reservoir. The aim and target of this service is the hope that the village community will have the motivation to develop the economy in the reservoir from tourists from surrounding villages or even various parts of the region in general, thus forming independent group members to be creative and responsive.

Magnetic Properties of Ancient Sediments Bengawan Solo, Central Java-East Java, Indonesia

Information about the eruption of Mount Lawu in Central Java Province in 1885 and Mount Merapi in D.I. Yogyakarta in 2010 became a source for estimating the presence of magnetic minerals which underwent a sedimentation process in the Bengawan Solo River from upstream (Wonogiri) - downstream (Bojonegoro). The results we get of the magnetic susceptibility distribution of the Bengawan Solo sediments reveal that the sediment from the upper reaches of the Bengawan Solo River has a low frequency magnetic susceptibility value in upstream of around 1,080.23×10−8 m3/Kg - 2,780.77×10−8 m3/Kg, the middle part is 74.40×10−8 m3/Kg - 1,735.90×10−8 m3/Kg, and downstream 17.57×10−8 m3/Kg - 1,620.53×10−8 m3/Kg. The value of magnetic susceptibility decreased significantly from upstream to downstream. High susceptibility indicates the sample contains metal elements. In determining iron oxide, we use X-Ray Fluorescence assisted by X-Ray Diffractometer testing to determine magnetic minerals. X-Ray Fluorescence confirm metal oxide in the sample. There are Al and Fe confirm the presence of magnetic properties in sedimentation. The Vibrating Sample Magnetometer confirmed that the Bengawan Solo sediment has a magnetic saturation about 0.06 - 9.50 (emu/g), a magnetic remanent around 0.001 - 0.575 (emu/g) and coercivity field of around 10 - 60.15 (Oe). X-Ray Diffractometer pattern confirm the mineral structures, namely Coesite, Magnetite, Cristobalite, Portlandite, Quartz, Anatase, Goethite, Tridymite, Gibsyte, Stishovite, Grasullaria, Labradorite and Wuestite. These results indicate the novelty of sediments from Bengawan Solo, Central Java to East Java. HIGHLIGHTS We found several important points in this research: The Bengawan Solo River is formed from several formations and lifting from faults The Bengawan Solo River is rich in minerals formed from metal oxides The magnetic value decreases with the distance from Mount Lawu The Bengawan Solo River has confirmed ferromagnetic properties from the S-type hysterisis curve With low magnetic remanent values, low saturation magnetism and high magnetic corrosivity GRAPHICAL ABSTRACT

The abundance of endocrine-disrupting chemicals (EDCs) in downstream of the Bengawan Solo and Brantas rivers located in Indonesia

Numerous chemical substances are used for daily life activities have an effect on the endocrine system and are frequently classed as endocrine-disrupting chemicals (EDCs). The present study investigated the fact and distribution of EDCs type (estrogen, plasticizer, and preservative). In particular, EDCs such as estriol, 1,2,4 triazole, 17α-ethinylestradiol, methyl paraben, estrone, 3,4,4 trichlorocarbanilide, 17β-estradiol, and bisphenol A (BPA) were selected as the target EDCs for the detection in the Bengawan Solo and Brantas rivers located in Indonesia. Among the targeted EDCs, BPA is found to be highest in the water samples of Bengawan Solo (1070 ng/L and mean at 219 ng/L) and Brantas (556 ng/L and mean at 222 ng/L) rivers. The EDCs concentration is higher in both rivers during the dry season compared to the wet season due to the dilution effect caused by heavy rainfall. The entry of municipal wastewater is the primary sources of EDCs contamination in both rivers. Finally, this study suggests that the contamination level of EDCs in river water could pose an environmental threat, particularly during dry seasons.

Study Of Macrozoobentos Diversity In The Secondary Flow Of The Bengawan Solo River

Macrozoobenthos are invertebrate animals that live on the bottom of the waters which are often used as an estimator of the imbalance in the physical, chemical, and biological environment of the waters. Polluted waters will affect the survival of macrozoobenthos organisms because they are easily affected by the presence of physical and chemical pollutants. This study aims to determine the diversity, abundance of macrozoobenthos as well as diversity index, evenness index, dominance index, and density index which can be used as a reference for determining the water quality of the Bengawan Solo River secondary flow in Tunjungmekar Village, Kalitengah District, Lamongan Regency. Researchers found 6 classes of gastropods, 1 class of bivalves, 1 class of crustaceans, 1 class of malacostraca, 1 class of clitella, from 10 types of macrozoobenthos. It is known that the diversity values ??of stations 1,2,3 and 4 are included in the low category, this is because the value of each station is &lt;1. The evenness value of stations 1,2,3 and 4 is included in the low category because each station is &lt;1. From the results of the dominance analysis, the highest value is at station 1 with a total of 0.59 because there are freshwater snail species that dominate at station 1. The highest value density is at station 1 with a value of (40.49) while the lowest value is at station 4 with a value of (2, 83). The highest density value is at station 1 with a value of (40.49) while the lowest value is at station 4 with a value of (2.83). The result water quality temperatures between 28.5-300C, brightness ranges from 19-21 cm, depth ranges from 0.5 - 2 m, the salinity of 0‰, pH from 8.5-8.8, dissolved oxygen (DO) ranged from 2.2 to 3.3 mg/L, nitrite ranged from 0.09-0.20 mg/l. The results of water quality measurements are still in good condition for the life of aquatic biota.

Analysis of social vulnerability index in Watershed Bengawan Solo downstream

Purpose of this research to know 1) the level of social vulnerability, 2) socio economic description, and 3) mapping of comparison of social vulnerability in Watershed of Bengawan Solo covering Bojonegoro, Tuban, Lamongan and Gresik. The method used in this research by using Social Vulnerability Index (SoVI) method as social vulnerability analysis tool and Geography Information System (GIS) analysis tool to map the area and its vulnerability level. The results showed the highest level of social vulnerability with the highest score of SoVI score obtained by Tuban Regency with SoVI score of 7, then Bojonegoro with SoVI score of 6, Lamongan with SoVI score of 4, and Gresik with SoVI score of 1. Bojonegoro And Kabupaten Tuban have the same highest score on the components of social vulnerability level, then Lamongan regency, and the lowest level of social vulnerability is in Gresik regency. For the grade of social vulnerability, Kabupaten Tuban and Bojonegoro are categorized into high social vulnerability classes, Lamongan District with moderate social vulnerability, and Gresik Regency with the lowest social vulnerability.