bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nutritional Content and Growth Ability of Duckweed Spirodela polyrhiza on Various Culture Media
Authors: Said D S , Chrismadha T , Mayasari N , Widiyanto T , Ramandita A 
Published: July 2022

Abstract
Giant duckweed (Spirodela polyrhiza) is one species of duckweed, distributed cosmopolitanly in stagnant freshwater. The duckweed has several potential uses such as for animal and fish feeds. However, its biological information in Indonesia is rare. A research was conducted in June to July 2019 to explore its nutritional content and growth ability. The growth ability experiment was done with two replications at The Research Center for Limnology, Indonesia Institute of Sciences laboratory. The indoor experiments used 3 types of culture media, namely P (mixture of Urea, NPK, and Gandasil); Q (water waste from catfish cultivation), and R (hydroponic fertilizer). Spirodela polyrhiza has a protein content of 24.10%; fat 1.74%; ash 1.78%, crude fiber 14.47%, and nitrogen-free extract of 57.89%. There were 15 types of amino acids observed in the biomass, made of as much as 13.1% w/w. The highest growth was obtained in R culture media with a specific growth rate (SGR): 8.54–16.53 % and productivity of 15.62–51.32 g/day/m2. Outdoor trials using the R media have a SGR value of 10.17–11.16% and productivity of 54.82–84.1 g/day/m2. Spirodela polyrhiza can be developed and have the potential to be used as an alternative natural feed source for aquaculture or another purpose. Further research is needed.
The condition and nutrient content of introduced freshwater shrimp Macrobrachium lanchesteri at two urban small ponds, Cibinong, West Java, Indonesia
Authors: Mayasari N , Said D S , Astuti M P 
Published: July 2022

Abstract
‘Situ’ Lotus and ‘Situ’ Cibuntu are small ponds located in urban areas at Cibinong Science Center-Botanical Garden, National Research and Innovation Agency, Indonesia. This study was conducted to determine the development of the introduced freshwater shrimp Macrobrachium lanchesteri in that ponds. Observations were carried out in January and February 2019. There are four sampling points in each pond. The number of shrimp obtained at Lotus Pond is more than Cibuntu Pond. The average total length and weight of shrimp obtained at Lotus Pond during the first observation were 1.61 – 2.55 cm and 0.07 – 0.20 gram, while the second was 1.67 – 2.27 cm and 0.11 – 0.31 gram. Meanwhile, M. lanchesteri obtained at Cibuntu Pond in the first observation had an average total length of 2.20 – 2.63 cm and weight 0.16 – 0.20 gram; and when the second sampling was 2.27 – 3.00 cm and 0.16 – 0.34 gram. Proximate analysis of shrimp from Cibuntu Pond showed that this shrimp’s protein, fat, ash, crude fiber, and carbohydrate content were 58.68%; 10.70%; 15.31%; 7.70%, and 7.61%, respectively. The water quality observed in both ponds is still good and can support the shrimp’s life. Utilization of this shrimp as an alternative source of protein can be done if pond water quality is always maintained in the future.
The Abundance and Potential Activity of Nitrifying, Denitrifying, and Nitrate-ammonifying Bacteria in the Vanamae Shrimp Culture in Karawang
Authors: Alfisah R K , Rusmana I , Widiyanto T , Affandi R 
Published: July 2022

Abstract
The existence of inorganic nitrogen in the shrimp pond ecosystem will not be separated from the nitrogen cycle and microbiological processes including the activity of microbes. This study aimed to analyze the abundance and potential rate of nitrifying, denitrifying, and nitrate-ammonifying bacteria in Vanamae shrimp cultivation. Water samples were collected on a shrimp pond in Karawang, West Java. Water sampling was carried out at the age of shrimp rearing 0 days, 21 days, 65 days, and 89 days. Water sampling was conducted at four points representing an area of the pond. The bacterial abundances were analyzed using Most Probable Number (MPN) method. The potential rates of bacteria were calculated by Michaelis-Menten kinetics. The highest abundance of nitrifying bacteria was 3.690 log cells ml-1 on 65 days, denitrifying bacteria was 3.415 log cells mL-1 on 89 days, and nitrate-ammonifying bacteria was 3.079 log cells mL-1 on 65 days of shrimp cultivation. The affinity of enzymes related to ammonia oxidation from nitrifying bacteria was higher than nitrate reduction from denitrifying and nitrate-ammonifying bacteria. Generally, nitrifying bacteria were the most abundant and dominant activity over shrimp cultivation.
Phytoplankton Diversity in Jakarta Bay Estuary, Indonesia
Authors: Susanti E , Widoretno M R , Prihatinningtyas E , Akhdiana I , Riffiani R , Henny C , Toruan R L 
Published: July 2022

Abstract
Phytoplankton plays an important role in aquatic ecosystems and is one of the biological parameters that can be used as bioindicators to describe conditions, quality, and environmental changes. Jakarta Bay is polluted by various wastes originating from industry, domestic, and sea transportation for fishing activities, which causes a decrease in water quality in Jakarta Bay. This study aims to reveal the composition of phytoplankton and its relationship with the physical and chemical parameters of the waters that empty into Jakarta Bay. The study was conducted in September 2021 at three sampling stations in estuary areas. Station 3 was the most polluted area from industrial waste, only found phytoplankton from the group of Cyanophyta (61.57%) and Euglenophyta (38.43%). Meanwhile, station 2 with the highest concentration of chlorophyll-a, contaminated with domestic waste was dominated by Cyanophyta (29.26%), Euglenophyta (11.79%), Chrysophyta (39.74%), and Chlorophyta (19.21%) groups. The water quality of the two sampling stations greatly affects the composition and abundance of phytoplankton.
Carbon, Nitrogen and C/N ratio of sediment in a floodplain lake: Lake Tempe, South Sulawesi
Authors: Yustiawati  , Syawal M S , Rosidah  
Published: July 2022

Abstract
The composition of carbon (C), nitrogen (N) and C/N ratio in the sediment lake provided valuable information about the sources of organic matter and depositional basin. In a floodplain lake, sediment deposition is very dynamic related to seasonal changes. The aim of the study is to reveal the composition of C, N and C/N ratio in sediment lake in the permanent zone and non-permanent inundation zones and to predict the sources of organic matter in sediment lake. The study was conducted in March 2017 in Lake Tempe, South Sulawesi, Indonesia. Sediment samples were collected from six zones. C-organic was determined according to modification of the Walkley-Black method. Nitrogen was determined by the Kjeldahl method. The result showed that carbon organic in this sediment lake was about 4.7 – 5.8 %. The lowest was found in the nonpermanent zone. The highest value was found in the permanent zone, indicating that the organic carbon has been accumulated for long period in this permanent zone. Nitrogen organic content in sediment was about 0.30 to 0.50 %, this value was relatively low. It probably nitrogen content has been released to the water column or rapidly up-taken by microbes. C/N ratio in the sediment of Lake Tempe was in the range 13.1 to 18.1, this value indicated that organic matter originated from a mixture of plankton and macrophytes.
Ecological Heterogeneity of Oxbow and Floodplain Lakes Along the Kapuas Riverine System
Authors: Subehi L , Uno H , Imroatushshoolikhah  , Sulastri  , Yustiawati  , Toruan R L , Ajie G S , Jasalesmana T , Dianto A , Afandi A Y , Sulawesty F , Julzarika A , Ramadhan Y , Triwati  , Nakano S 
Published: July 2022

Abstract
Kapuas River in West Kalimantan with over 1,143 km is the largest river in Indonesia. It serves as a main refuge for high potential biodiversity. Oxbow lakes along the Kapuas River are of high ecological essential due to the number and the diversity of habitats they provide. In addition, oxbow lakes are critical components of the floodplain systems of lowland rivers. The objective of this study was to explore the diversity of oxbow lakes and their connectivity to the main river. We conducted fieldwork to measure water quality and ecological components at 12 oxbow lakes along the Kapuas River and two lakes in the Sentarum complex in January - February 2020. We measured the environmental parameters including water depth, water temperature, Secchi/transparency, pH, dissolved oxygen concentration, chlorophyll-a concentration, total nitrogen, and total phosphorus concentrations. Aquatic biota, including phytoplankton and zooplankton community structures, were also observed at 12 oxbow lakes along the Kapuas River and two lakes in the Sentraum complex. The sampling points represented both permanent and non-permanent connectivity of the oxbow lakes to the main river. The result indicates the variability of environmental characteristics between the lakes, based on water quality and biota analysis; for example, water acidity, as indicated by pH, was likely to seem like the main variable determining the oxbow lake biota. Also, the habitat connectivity of oxbow lakes to the main river has significantly influenced the biotic composition.
Land Ocean Connectivity Through Inland Water Ecosystem: A Coremap-CTI Project in The Coastal Area of Kendari Bay, Southeast Sulawesi
Authors: Santoso A B , Apip  , Wibowo H , Aisyah S 
Published: July 2022

Abstract
Coastal zone is highly valued ecosystem exposed to multiple and often cumulative natural and anthropogenic stressors such as catchment loads of nutrients and sediment, as well as climate warming. High loads of nutrients and sediment from the hinterland are dispersed into this zone leading to an increase microalgae community in which it may reduce light availability for corals and seagrasses. In this paper, we present the progress of our study in the coastal area of Kendari, Southeast Sulawesi, under the COREMAP-CTI Research Programme. Through such programme we are 1) investigating the flux of materials from the river basin to the marine environment, 2) characterising the key process that governing those fluxes, 3) developing models that capable of in predicting material fluxes under current and future environment (e.g., land-use and climate change). To do so, we integrate data and information derived from field observations and satellite imagery analysis to feed the developed rainfall-sediment-runoff and coastal ecological-hydrodynamic model. Not only focusing on the science of physical-biogeochemical processes of land-ocean interaction, the outcome of this research project is also aimed to support the development of adaptation strategy in combating climate change and anthropogenic pressure in the near future of coastal ecosystem.
Influence of Rainfall and Spatial Temporal Distribution Analysis of Total Suspended Solid in Laut Tawar Lake
Authors: Adhar S , Lukman  , Khalil M , Ayuzar E , Erlangga  , Rusydi R , Mainisa  , Muliani  
Published: July 2022

Abstract
Total Suspended Solid (TSS) is a solid particle suspended in the water column of organic and inorganic materials, sized more than two micrometers. The high concentration of TSS in the waters causes a decrease in water clarity and potentially reduces dissolved oxygen that can threaten the life of aquatic biota. This study aims to analyze the spatial and temporal distribution of TSS and analyze the influence of rainfall on TSS in Laut Tawar Lake waters. The lake TSS ranged from 44 – 91 mg/L with an average of 68.67 ± 11.23 mg/L. Spatially TSS ranged from 63.17 - 73.67 mg/L and temporally ranged from 51.14 - 81.43 mg/L. The distribution of TSS was not spatially different because the lake waters are perfectly agitated. The difference in TSS was obtained temporally due to the influence of rainfall. The catchment area can be eroded by only 100 mm of rain/month. It leads to high production of TSS loading into the lake waters. It was indicated by the difference in TSS of Dry Months with TSS of Wet and Moist Months. The determinant coefficient of influence of rainfall on the TSS concentration of the lake waters is 0.62.
Mercury Contamination on Aquatic Organisms in related to Artisanal Small-scale Gold Mining Activity in Indonesia: A Mini Review
Authors: Yoga G P , Sari A A , Nurhati I S , Yustiawati  , Andreas  , Hindarti D 
Published: July 2022

Abstract
Artisanal Small Scale Gold Mining (ASGM) is the largest source of Hg pollution in the environment. Indonesia has ratified the Minamata convention in 2013. Mercury pollution to the aquatic environment is a great concern due to its potential impact may threat the aquatic ecosystem. In this study we conduct a mini literature review dealing with the impact of mercury pollution on aquatic organisms in Indonesia, this study provides an overview of mercury contamination in fish and macroinvertebrates in Indonesia which is related to ASGM activities, based on peer-reviewed literature recorded in the Scopus database (www.scopus.com). Keywords mercury OR Hg AND ASGM AND Indonesia was used to retrieve literatures from the database. The identified articles were screened for relevance at the title, abstract, and full text level using predefined inclusion criteria. The mercury accumulation in freshwater fish and macroinvertebrates were ranged from 0.005 mg/kg to 19 mg/kg, and from 0.002 mg/kg to 1,46 mg/kg, respectively. While mercury accumulation in in marine fish and macroinvertebrates were from 0,014 mg/kg to 57 mg/kg and 0.002 mg/kg to 2.99 mg/kg, respectively. The highest mercury accumulation in freshwater fish was found in Manado, North Sulawesi and the lowest was in Talawaan Watershed, North Sulawesi, while in Marine fish, the highest Hg accumulation was also found in Manado, North Sulawesi, and the lowest accumulation was found in Buyat, North Sulawesi. Introduction
Exploration of cyanobacteria as bioremediation candidates to reduce phosphorus contamination
Authors: Asih D R , Summerfield T C , Eaton-Rye J J 
Published: July 2022

Abstract
The aim of this research is to evaluate cyanobacteria as a bioremediation agent for the removal of inorganic phosphate. We have adopted two approaches. The first approach involves the inactivation of the sphU gene in a model cyanobacterium. This gene encodes a negative regulator of the pho-regulon, this regulon includes genes involved in phosphate uptake. Inactivation of sphU results in the constitutive uptake of inorganic phosphate and its accumulation in polyphosphate bodies within cyanobacterial cells. Preliminary data using Synechocystis sp. PCC 6803 has shown that the ΔSphU strain removed 96% of phosphate from the growth medium in 36 h whereas a similar phosphate depletion by wild-type cells took ~72 h. Our second approach involves the screening of native cyanobacteria to identify strains that have optimised their ability to take up phosphate. Our goal is to evaluate suitable cyanobacteria for phosphate uptake. This will be achieved through mesocosm studies designed to assess the ability of the cyanobacteria to selectively remove phosphate with the accompanying generation of biomass with potential to be used as feedstock for various biotechnological applications.
Environmental Quality Identification of Wangi the River Polluted by Waste Based on the Environmental Pollution Index
Authors: Adam M A , Khumaidi A , Ramli  , Ernawati  , Widiastuti I M , Risjani Y , Soegianto A 
Published: July 2022

Abstract
High amount of wastewater release to Wangi riverflow, especially industrial wastewater, can potentially cause pollution. Pollution in river has been occurred since 2015. The aim of this study was to identify the environmental quality of contaminated Wangi River and determine the pollution index. This study was performed through a survey method, and river water sampling was carried out around the Wangi riverflow, Beujeng-Beji, Pasuruan District. Sampling was conducted in three locations, namely industrial, residential, and agricultural areas on different months (June 2020 - July 2021). This study was also conducted to analyze the heavy metal content of Pb, Hg and Cd in Wangi river biota around the watershed, namely mosquito fish (Gambusia affinis). The pollutant identification result was based onthree study areas, namely study area I (factory/industrial waste), study area II (residential waste) and study area III (agricultural waste). Heavy metal contamination occurred in Wangi River hhe as the potential to produce waste containing Pb, Cd and Hg. The average levels of Pb, Cd and Hg in the water were 0.031 ppm, 0.019 and 0.009 ppm, respectively. These values exceeded the acceptable quality standard. The result of data analysis based on the pollution index (PI) and average number of pollution indexes (PIaverage) in the Wangi river (at study areas I, II and III) was 5.503, which means thatthe condition of the Wangi river is classified as a “moderately-polluted” river. The authority is expected to develop a further policy for Wangi riverflow preservation program.
Mahakam River Potency as Raw Water to Support Drinking Water Services and Sanitation in the New Territories of the State Capital, East Kalimantan
Authors: Sutapa I D A , Nurhidayat A , Prihatinningtyas E 
Published: July 2022

Abstract
The Indonesia Government’s decision to move the country’s capital city from DKI Jakarta on the Java island to Penajam – Paser Utara in East Kalimantan provides new hope and challenges that must be faced. The pressure on the environment due to anthropogenic activities, industry, transportation, business, trade, tourism, etc., causes the Jakarta area not to have a good ecosystem and environmental carrying capacity. Some basic needs that have not been fully addressed so far are drinking water, sanitation, and health services for the community and need serious attention in the development planning of the new national capital. The limitations of raw water in terms of quality, quantity, and continuity are often the main obstacles to ensuring the fulfillment of drinking water and sanitation according to appropriate needs. East Kalimantan region has many surface water resources consisting of rivers, lakes, swamps, and springs. The Mahakam River is one of the major rivers in this region, which has a potential source of raw water to be processed into clean water and drinking water. This study aims to examine the potency of Mahakam river water as raw water to support drinking water and sanitation services availability. The results showed that the water of the Makaham river in the city of Samarinda experienced daily ups and downs with a difference in water level of 2 m. Meanwhile, the turbidity level of river water varies between 185 to 229 NTU. Mahakam river water is categorized as C - D quality, with sufficient quantity and continuity. A complete treatment system is needed to improve its quality to clean water or drinking water in accordance with the standards.
Inland Water Trophic State Identification using Remote Sensing data and Machine Learning Approach
Authors: Setiawan F , Jiang D , Hamzah R , Matsushita B 
Published: July 2022

Abstract
Providing information on inland waters’ trophic state levels (oligotrophic, mesotrophic, eutrophic, and hypereutrophic) is considered more effective in communicating the lake’s conditions to the public and policymakers than water quality. It is highly demanding for a straightforward method to estimate inland waters’ trophic state. This study proposes a model for estimating the lake trophic state levels from remote sensing data. We used simulation data to overcome data limitations in building the classification model. The simulation data consists of one nanometer (nm) interval spectra, paired with calculated Secchi Disk Depth (SD in m) representing various water types. We convert the spectra into Landsat band configuration and classify SD into four trophic state levels. We compare four machine learning classification models, i.e., Classification and Regression Trees (CART), k-Nearest Neighbour (k-NN), Support Vector Machine (SVM), Random Forest (RF), and select the best model using the Kappa Index. We apply the selected model to satellite images and estimate trophic state levels of various lakes across time and space. Our result demonstrated that the developed model could robustly identify the lake trophic state levels. This rapid identification procedure could provide valuable spatial and temporal information of the lake’s conditions for the public and policymakers to support inland water sustainable management.
Analysis of Normalized Different Wetness Index (NDWI) Using Landsat Imagery in the Ciletuh Geopark Area as Ecosystem Monitoring
Authors: Rahmat A. , Daruati D. , Ramadhani W S , Ratnawati H I 
Published: July 2022

Abstract
Geopark is a park area that is included in a conservation area, which has elements of geodiversity, biodiversity, and cultural diversity. It has aspects in education as knowledge earth science and tourism. One of the geoparks on the Java island that concern the government is the Ciletuh Geopark. Besides the potential, the Ciletuh Geopark landscape also has threats such as floods and droughts that can disrupt its ecological function. Therefore, it is necessary to conduct a study related to the wetness status of the Ciletuh Geopark to minimize the impact of floods and droughts. One way is by using the Normalized Different Wetness Index (NDWI). This study aimed to analyze the level of wetness of the Ciletuh Geopark with the Normalized Different Wetness Index method obtained from Landsat images. The results show that compared to 2001, the area with moderate wetness and high wetness decreased almost 50% in 2015, and the non-water body increased twice. On the other hand, the wetness condition did not significantly change between 2015 and 2021. The decreasing the wetness condition suspected by drought due to global climate change.
Optical cloaking of macroscopic objects by geometric-phase vortex processing
Authors: Rafayelyan Mushegh , Melkonyan Henrik , Tigranyan Arman , Brasselet Etienne 
Published: July 2022

Abstract
We report on free-space strategy for electromagnetic concealment of three-dimensional macroscopic objects in the optical domain owing to unique energy flow redirection capabilities enabled by optical phase singularities. We propose and implement the generation of a quasi-nodal volume based on optical vortex Fourier processing, which inhibits light scattering from objects placed inside. The proof of concept is made by numerical simulations and the experimental implementation is carried out in the visible domain by using geometric phase vortex phase masks. Optical cloaking demonstration is made by using stainless steel sphere as the object to be concealed. The geometric phase nature of the vortex masks confers polarization independent features to the device and makes it possible to implement in a reflection mode.