bluuebunny/crossref_metadata_2025 huggingface dataset:
The influence of casing treatment on the performance of a centrifugal pump
Authors: Li Yuan , Chen Hua , Li Xiangjun , Jiang Minghe , Wang Guinian
Published: May 2021

Centrifugal pumps may run under off-design conditions such as low flows. Under such conditions, back-flow may occur at the impeller inlet and block a part of the flow path and cause energy loss. Casing treatment has been widely used in centrifugal compressors to improve their performance at low flow conditions, but there is little in the open literature on the effect of casing treatment on the performance of centrifugal pumps. In this paper, a SC100-200 centrifugal pump is studied with a casing treatment. First, the CFD method employed was described and verified by the experimental results of the pump. CFD indicates that the starting point of the back-flow is around discharge coefficient of 0.111 of the pump, and the back-flow intensity gradually increases with the decrease of flow rate reaching another critical point at discharge coefficient of 0.061 where the back-flow upstream traveling distance suddenly increases significantly. Then a casing treatment is created in the inlet end-wall and front cover using a U-tube type configuration. The numerical simulation was carried and it is found that a part of the back-flow at the inlet and front-side cavity of the centrifugal pump is sucked to the U-tube of the casing treatment and returns to the pump inlet, the back-flow and entropy production at the impeller inlet are reduced, and the head and efficiency of the pump is little affected. Further research shows that the longer the length of the U-tube is, the stronger the suction effect will be, and the smaller the back-flow of the pump.
Evaluation of natural frequency, Campbell diagram and forced torsional vibration of deepwell pumps for the marine, oil and gas industry
Authors: Bayat M. , Sørensen H.L.
Published: May 2021

Deepwell marine and offshore pumps need to design in a way to present high performance and reliable lifetime. Deepwell pumps should be designed in a way to operate under offshore conditions. In order to investigate the resonance and find critical rotational speeds of the pump, it is needed to find the rotational natural frequency for undamped model. In order to avoid any resonance, the intersection points between natural frequency and excitation (1X and 2X) should not be in the interval of 90%-110% of operating speed, based on API standard (API 610). Deepwell pump structure is combination of motor, motor-shaft coupling and pumping configuration. Based on the size of tank and type of ship the length of whole deepwell pump can be more than 40 meters. Elastic rotating shafts connect with appropriate shaft-couplings with needed numbers of impellers and inducer. Small and linear angle of rotation theory are used to extract natural frequencies of deepwell pumps. Different damping scenarios are illustrated in detail. Holzer method is implemented to analyse torsional forced vibration. Free-free boundary conditions considered. Combination of discrete model, lumped mass model and finite element method are employed to present the Campbell diagram. Parametric strategy is used for forced torsional vibration analysis. It is found that how to model and consider the effective length of intermediate shaft in pumping configuration has effect on second natural frequency. It is seen that the first natural frequency of the whole system is highly depended on modelling of motor-shaft coupling. The results are compared when the whole pump is model by lamped mass model and finite element model. Results of this paper suggest that combination of three mentioned methods is acceptable and accurate. It is shown that Holzer method is suitable for torsional forced vibration analysis. The developed codes are verified with findings in the literature.
Assessment of the Influence of Boundary Layer Ingestion (BLI) on the Axial Fan
Authors: Masaki A , Ogushi S , Tsuruta R , Nishiwaki D , Sato T , Okai K , Kazawa J , Masaki D , Harada M
Published: May 2021

Boundary Layer Ingestion (BLI) is a technology which is effective to reduce fuel consumption of future commercial aircrafts. However, the inlet distortion caused by BLI has a negative on the engine performance. This paper investigates the effect of the inlet total pressure distortion on the aerodynamic performance of the fan rotor. Unsteady numerical analysis was conducted on JAXA TechClean Fan with circumferential distortion caused by BLI. As the result, under the high distorted condition, the peak efficiency of the rotor decreases by 0.622 points. It is found that the main factor of the efficiency reduction is tip-wall passage vortex.
Aerodynamic and Mechanic Analyses of An Asymmetrically Scalloped Radial Turbine
Authors: Wang Yu , Chen Hua , Ma Chao , Sun Jinhui
Published: May 2021

In order to reduce the aerodynamic efficiency loss of deeply scalloped radial turbines, asymmetrically scalloping of turbines’ backdisc has been invented for a number of years. However, the mechanism how this works and its mechanical implication have not been reported in the open literature. In this paper, taking the symmetrically scalloped turbine of a turbocharger for marine generator application as the baseline, two asymmetrically scalloped turbines were developed from it: one with scalloping bias to the pressure side, and the other to the suction side of the blades. Mechanic and aerodynamic analyses of these three turbines were carried out using ANSYS Workbench. The results indicate that the asymmetrically scalloped turbine with scalloping bias to the pressure side can reduce the backdisc-heat shield cavity leakage flow going into the blade suction surface through the scalloped backdisc, due to the influence of the high pressure near the pressure surface of the blade, thus decrease the size of vortices the leakage flow generated near the suction surface inside the blade passages and associated mixing loss. Compared to the symmetrically scalloped turbine, it increases the maximum principal stress by 0.39% and 5.2% at blade fillet and backdisc respectively, but the aerodynamic efficiency of the turbine is increased by 0.78% point at a turbine U/C value of 0.43, and the smaller the value of the U/C is, the greater the efficiency advantage will be. By contrast, the turbine with suction side bias scalloping shows the poorest aerodynamic performance, due to an increased leakage flow through its scalloped backdisc.
Animal waste use and implications to agricultural greenhouse gas emissions in the United States
Authors: Qin Zhangcai , Deng Shiyu , Dunn Jennifer , Smith Pete , Sun Wenjuan
Published: May 2021

The increasing production of manure is a challenge for livestock management systems as well as the global environment. Being traditionally, and still dominantly, used as fertilizers, land application of manure could preserve soil fertility and improve soil carbon sequestration. However, manure application also increases nitrous oxide (N2O) emissions that might outweigh the benefits of carbon gains. Here we quantify soil carbon change and greenhouse gas (GHG) emissions from corn production systems in the United States from a life-cycle perspective. We show that utilizing manure can reduce mineral fertilizers use, and therefore avoid GHG emissions that would otherwise occur due to mineral fertilizer production and application. As a result, corn produced under manure has a reduced intensity of GHG emissions (1.5 t CO2e ha−1 or 0.15 t CO2e t−1 corn grain), about 15% less than those under sole mineral fertilizers. Owing to a sizeable amount of avoided emissions counterbalancing N2O, the soil carbon gain derived from manure use can largely contribute to net climate change mitigation. It should be noted that GHG emissions estimation can be largely improved as more robust and recent data become available to better represent spatially specific land management and to integrate ecosystem models with life-cycle model. Future studies are merited to further assess the alternative fate of manure, and expand the system boundary to assess agriculture and livestock sectors holistically.
Machine learning analyses of remote sensing measurements establish strong relationships between vegetation and snow depth in the boreal forest of Interior Alaska
Authors: Douglas Thomas A , Zhang Caiyun
Published: May 2021

The seasonal snowpack plays a critical role in Arctic and boreal hydrologic and ecologic processes. Though snow depth can be markedly different from one season to another there are strong repeated relationships between ecotype and snowpack depth. In the diverse vegetative cover of the boreal forest of Interior Alaska, a warming climate has shortened the winter season. Alterations to the seasonal snowpack, which plays a critical role in regulating wintertime soil thermal conditions, have major ramifications for near-surface permafrost. Therefore, relationships between vegetation and snowpack depth are critical for identifying how present and projected future changes in winter season processes or land cover will affect permafrost. Vegetation and snow cover areal extent can be assessed rapidly over large spatial scales with remote sensing methods, however, measuring snow depth remotely has proven difficult. This makes snow depth–vegetation relationships a potential means of assessing snowpack characteristics. In this study, we combined airborne hyperspectral and LiDAR data with machine learning methods to characterize relationships between ecotype and the end of winter snowpack depth. More than 26 000 snow depth measurements were collected between 2014 and 2019 at three field sites representing common boreal ecoregion land cover types. Our results show hyperspectral measurements account for two thirds or more of the variance in the relationship between ecotype and snow depth. Of the three modeling approaches we used, support vector machine yields slightly stronger statistical correlations between snowpack depth and ecotype for most winters. An ensemble analysis of model outputs using hyperspectral and LiDAR measurements yields the strongest relationships between ecotype and snow depth. Our results can be applied across the boreal biome to model the coupling effects between vegetation and snowpack depth.
Physicochemical characterization of peel, flesh and banana fruit cv. raja [Musa paradisiaca]
Authors: Syukriani L , Febjislami S , Lubis D S , Hidayati R , Asben A , Suliansyah I , Jamsari J
Published: May 2021

All parts of a banana cv. Raja can be used as functional food and health or beauty products. The physicochemical properties of fruit peels, pulp and banana cv Raja need to be known to determine the type of processing because it can affect the final product processed. This research aimed were to determine the characteristics of banana cv. Raja Flour from peel, flesh and fruit and its minerals content. The results obtained from the analysis of moisture content ranged from 6.21 to 39.33%, ash content was 1.33-1.86%, protein content was 2%. The content of vitamin C in the peel, fruit and flesh of bananas is 32.3 mg/100 g, 7.18 mg/100g and 4.99 mg/100g respectively. The mineral content of potassium (K) and calcium (Ca), in banana peels, is higher than the flesh and fruit of bananas, such as 73.03% and 16.12%, while the content of phosphorus (P), magnesium (Mg) and chlorine (Cl) in The pulp was higher than the skin and banana fruit 10.52%, 6.58%, and 4.37% respectively. The crystalline structure of banana flour from banana peels, fruit flesh and fruit shows the same type is type A and the gelatinization temperature ranges from 74.85 to 76.90C within 8.6 to 10.6 minutes.
The productivity of paddy rice with the method of five seedlings clump-1 STSS used PHP mulch and furrow irrigation compared with several cultivation technology packages
Authors: Sunadi  , Utama M Z H , Badal B
Published: May 2021

Various cultivation technique innovations such as the SRI method with AWD irrigation system have been able to increase the productivity of paddy rice, but farmers are still reluctant to implement it because they are faced with weed problems. This study aimed to test the productivity level of several paddy rice cultivation technology packages. The treatment was 6 types of cultivation technology packages, namely: the SRI method, the method with 5 seedlings clump−1 of STSS, the legowo system 4:1, the SBSU, the method of 5 seedlings clump−1 STSS with PHP mulch and furrow irrigation, and conventional system. The seedling was planted at 12 DAS ages, except for the conventional system at 26 DAS ages with 4 seeds attached clump−1. The results showed that the type of paddy rice cultivation technology package generally affected the growth and yield components of paddy rice, except for the percentage of productive tillers, the number of grain panicle−1, and the harvest index. The method of 5 seedlings clump−1 STSS with PHP mulch and furrow irrigation resulted more in almost all parameters compared to all packages technology tested. The grain production is 7,250 t MDG ha−1 it higher than other technology packages production.
Expression induction of Serratia plymuthica UBCF_13 metalloprotease gene with various types of metal ions
Authors: Zulfitri R , Aisyah S N , Oktavioni M , Fatiah R , Jamsari J
Published: May 2021

Bacteria as biocontrol agents can produce hydrolytic enzymes, one of them is a protease which plays an important role to degrade cell membranes or plasmalemma in fungi composed of protein. Metalloproteases are proteases that contain one or two metal ions on their active sites. The role of metal ions in metalloproteases is to activate water molecules, which act as nucleophiles in the catalysis process. The metalloprotease function of Serratia plymuthica UBCF_13 is unknown, therefore this study aimed to determine the effective metal ion to induce the expression of the UBCF_13 metalloprotease gene. The metalloprotease gene from Serratia plymuthica UBCF_13 was ligated into a pGEM T-easy plasmid. The recombinant plasmid was transformed into Escherichia coli BL21 by the heat shock method. The metalloprotease gene expression was induced by IPTG and a combination of several metal ions namely Zn2+, Mn2+, Fe2+, and Ca2+. The highest gene expression was characterized by the thickest protein band based on the result of SDS-PAGE visualization with a molecular weight of 27 kDa after being induced by Fe2+ metal ions. Proteolytic activity of metalloprotease UBCF_13 was tested using solid LB media containing 2% skim milk. The longest clear zone diameter was obtained up to 0,83 cm after being induced by IPTG combined with Ca2+ metal ion. These results can be used as a reference for the expression of the UBCF_13 metalloprotease gene. However, further enzyme purification is to be able the enzyme as an antifungal compound.
Cloning of gyrB housekeeping gene from Serratia plymuthica UBCF_13
Authors: Azizah N , Fatiah R , Jamsari J
Published: May 2021

Serratia plymuthica strain UBCF_13 is a biocontrol agent that has the potential to inhibit pathogenic fungi. S. plymuthica has housekeeping genes, one of which is the gyrB gene. The housekeeping gene was cloned to be used as a template for standard curve creation regarding the correlation of gene copy number and Ct value in absolute quantification data. This study was conducted to provide the plasmid housekeeping gene gyrB from S. plymuthica which will be used as a template for standard curve creation in absolute quantification. The method used in this study were DNA genome isolation, PCR, ligation, and transformation. The result showed that the housekeeping gene gyrB has been successfully cloning based on the size of the estimated amplicon, which is 114 bp.
Optimization of growth regulators to induce callus in chili [Capsicum annuum] cv. Berangkai
Authors: Yunita R , Bagus F R M , Nova B , Rosadi F N , Jamsari J
Published: May 2021

The imbalance between demand and yield production causes the price of chili to rise sharply in the market at a particular time. One of the factors driving chili productivity to decrease is the attack of Geminivirus. Geminivirus that attacks chili plant is Pepper Yellow Leaf Curl Virus [PepYLCV]. and causing failure in chili production. Therefore, it is necessary to develop chili varieties that are resistant to PepYLCD by applying a combination strategy of genetic engineering and a tissue culture approach. However, the morphogenetic ability of chilies to regenerate into complete plants is low in developing this strategy. Optimizing growth regulators in the media of callus induction can increase the morphogenetic response of chilies. This research aimed to obtain the optimal composition of callus induction media. The results showed that the use of the media composition of 2.5 mg/L NAA + 2.5 mg/L IAA and 3.5 mg/L 2.4 D + 0.25 mg/L TDZ could initiate callus formation on the eighth day after induction. Both media compositions have a callus growth percentage of about 100%, which has a friable and yellowish-white callus morphology.
Molecular characterization of andalas tree dioecious plant [Morus macroura Miq.] using SRAP marker
Authors: Aseny N , Syamsuardi S , Nurainas N
Published: May 2021

Sumatran Mulberry [Morus macroura var. Macroura] is the mascot [identity] flora of West Sumatra. Clarification of individual sex and genetic variation is necessary for its conservation. The SRAP [Sequence Related Amplified Polymorphism] marker system is one of the powerful molecular tools for clarification of individual sex and estimating its genetic diversity of plant species. The purpose of this study was to examine the male and female individuals in Andalas [Morus macroura] trees and to analyze their genetic variation. The fifteen individuals [accessions] of Morus macroura from three locations in West Sumatra [Limau Manis, Padang, Lubuak Gadang, South Solok and Andaleh, Tanah Datar] were collected to provide the DNA samples. A combination of seven primers was used to amplify the fifteens of DNA samples. Specific bands for the sex were examined in selected individuals, and Geneticvariation with four parameters: Number of allele [na], Number of effective allele [ne], Gene Diversity [h]; Shannon’s Information Index [I] were analyzed. The PCR Test indicated that Fifty fragments were obtained from the amplification of DNA samples using seven combinations of primers. The most number of fragments were found in the combination of primer B and E. The specific band at The 20 bp and 30 fragments were useful to distinguish the sex of the examined individual trees. The genetic variation of Morus macroura was moderate low [na=1.540; ne=1.273; h=0.168; and I=0.259]. Genetic diversity of Limau Manis Population [h=0.241] was higher than Lubuak Gadang [h=0.116] and Andaleh population [h=0.148].
Screening of Anti-MRSA metabolites in bacteria symbiotic with Batissa violaceae celebensis marten 1897
Authors: Rasyid S A , Lena D W A , As’Ad S , Miskad U A , Minhajat R , Surya R A
Published: May 2021

Currently, infectious diseases are still a serious problem in Indonesia, especially with thewidespread resistance of microbes to antibiotics. Staphylococcus aureus as one of the commonpathogens causing infection has experienced resistance to various classes of beta-lactam antibiotics known as Methicillin-resistant Staphylococcus aureus (MRSA). Therefore antibiotic alternatives sourced from nature are needed to treat the MRSA pathogenic infection. This study aims to explore the potential of bacteria in symbiosis with Pokea Shells (Batissaviolaceacelebensis Martens 1897) from Konawe Regency, Southeast Sulawesi Province to be used as the newest anti-MRSA. In this research, Pokea Shell’s symbiont bacteria were isolated from Konawe Regency to obtain pure isolates. Pure isolates that have been produced from secondary metabolites to be tested for their potential in inhibiting the growth of pathogenic bacteria MRSA. The inhibition test was done qualitatively by using a paper disk. Based on the results five bacterial isolates were obtained with different abilities to inhibit MRSA bacteria. Based on the qualitative test obtained that the Bvc1 and Bvc3 bacterial isolates had the potency to be used as anti-MRSA agents. These isolates have an inhibition zone of 25 mm and 22 mm with a sensitive category according to CLSI standards (Sensitive ≥17 mm). Determination of the gram of these 2 isolates found as gram-positive bacteria in the form of bacilli so it can be concluded that the 2 isolates can be used as anti-MRSA agents.
The Degradation of G3BP2 by Trim-away Method Inhibits Oscillatory Shear Stress induced Endothelial Cell Inflammation
Authors: Safitri M , Li T , Sihombing M A E M , Qiu J , Wang G
Published: May 2021

Progress in medical science has shown that cardiovascular pathogenesis is a complex disease with multiple underlying factors. Stress factors such as oxidative stress and oscillatory shear stress (OSS) play a crucial role in the occurrence and development of atherosclerosis as the major cause of cardiovascular diseases (CVD). However, study related the effect of stress on the development of human coronary atherosclerosis is not yet fully understood. Ras-GTPase-activating protein SH3 domain-binding proteins 2 (G3BP2) are multi-functional RNA binding proteins in which biomechanically sensitive gene that known important in cancer progression. Here in this study, we further explore the roles of G3BP2 protein especially their relation with atherosclerosis diseases, by investigating the G3BP2 regulation under biomechanical stress stimuli follows with the strategy of exploring the effect of G3BP2 disruption in endothelial cells by the application of new protein depletion technology called Trim-away. The result showed that oxidative stress and oscillatory shear stress (OSS) stimuli activated the expression of G3BP2 protein in primary endothelial cells. Moreover, the western blot analysis revealed that degradation of G3BP2 protein using Trim-away in endothelial cells induced OSS inhibits the release of the pro-inflammatory cytokines (VCAM-1 and ICAM-1). The compelling evidence demonstrated that suppression of G3BP2 protein expression in HUVECs potentially inhibits the development of atherosclerosis by decreased endothelial inflammation response.
Gambir catechins modulates amyloid-β concentration in cerebrospinal fluid of Alzheimer’s model rat
Authors: Fasrini UU , Lipoeto NI
Published: May 2021

Neurodegeneration in Alzheimer’s disease has been reported as the consequences of amyloid-β accumulation in the brain resulted from oxidative stress. Gambir, which contains catechins as a potential antioxidant, is abundant in West Sumatra. This study aims to evaluate the effect of gambir catechins administration on amyloid-β concentration in cerebrospinal fluid [CSF] of the rats. An experimental study with a post-test only design was carried out on 12-week old female Sprague Dawley, an Alzheimer’s model rat. As many as 30 rats were divided into the control and treatment groups. Four of the six groups were treated with the catechins extract doses of 20 mg, 40 mg, 60 mg, and 100 mg per 200 g BW. Meanwhile, the other two groups were positive and negative control groups. After four weeks, the rats were sacrificed and the CSF was collected. Amyloid-β concentration measurement was using the ELISA method. The statistical analysis was using One-way ANOVA with posthoc test Tukey HSD. Treatment groups exhibited a linear decrease in amyloid-β concentration in all doses, particularly in CC3. The CC3-treated group showed the lowest amyloid-β concentration [13.325 ± 4.625 ng/ml], which is significantly lower [p < 0.05] when compared to the PC group [45.280 ± 7.590 ng/ml]. This result provides experimental evidence that gambir catechin reached its optimum neuroprotective effect on amyloid-β level in cerebrospinal fluid by 60 mg/200 g BW.
Export performance and export competitiveness of Indonesia’s CPO industry with RSPO in China and EU markets
Authors: Alii H , Karimi S , Febriamansyah R
Published: May 2021

The implementation of the RSPO [Roundtable on sustainable palm oil] has been implemented since 2012 in the UE market, but the Chinese market has not. This study aims to describe and compare the export performance and export competitiveness of Indonesia’s CPO [crude palm oil] trade in both markets. Descriptive analysis was carried out on export performance and export competitiveness in the markets of China and the European Union [EU-25]. Statistical analysis used analysis compare means independent sample t-test and paired samples test. The results of the descriptive analysis found that there were significant differences in export performance and export competitiveness of Indonesia’s CPO trade in the China and EU-25 markets, with an average RCA to the Chinese market [23.65%], while the EU-25 market [109.27%]. The results of the comparison mean analysis of the independent sample t-test showed that there was no difference in trade value, but there was a significant difference in the trade quantity in the China and EU-25 markets There is a significant difference in the export competitiveness of Indonesia’s CPO trade in the China and EU-25 markets The results of the compare means paired samples test showed that there was no significant difference in the performance of Indonesia’s CPO exports to the China and European Union markets. However, there are differences in the competitiveness of Indonesian CPO exports in the Chinese and EU-25 markets due to the RSPO policy. This study recommends that in the future the RSPO should become a reference for developing the CPO export market.
Impact of COVID-19 outbreak on horticultural farming in Tanah Datar Regency of West Sumatra Province, Indonesia
Authors: Triana L , Mahdi M , Azhari R
Published: May 2021

The COVID-19 outbreak affects almost all sectors of farmers’ life. The lockdown policy has resulted in limited movement of farmers in carrying out social and economic activities. This study aims to identify those difficulties for horticultural farmers’ households during the COVID-19 outbreak and analyze its impact on household income. We had carried out an online household survey, for data collection by interviewing 86 horticulture farmers, who were randomly sampled in two horticulture production centers in Tanah Datar District. We found that almost 50% of farmers are having difficulty accessing agricultural inputs during the pandemic, such as seeds, fertilizers, and pesticides. This happened because of implementing a lockdown policy., which disrupts farmers’ smooth access to farm inputs. However, although almost half of the farmers have difficulty accessing farm inputs, the regression results show that the COVID-19 outbreak does not significantly affect household income. Based on our research, 96.5% of farmers were still farming and 55.8% of them were still working in the fields as usual. The difficulty for horticultural farmer’s households during the Covid-19 outbreak was increasing household expenditure such as for communication, health, education, and social/religion. They have to use household savings to overcome.
Management practices and stakeholder interactions along with sacred groves in Kerala
Authors: Sreelekha K , Joy Rosewine
Published: May 2021

Various developmental practices and changes in the social fabric threaten the existence of the local forest ecosystems such as sacred groves. A sacred grove, a forest common, traditionally has religious importance and unique management systems in place due to its cultural value. Sacred groves were in the ownership of a family or a community and had multiple stakeholders such as deity, devotees, communities, trusts. However rapid urbanization, increasing demographic demands negatively impact the sacred groves. With increasing stress on commercialization, the role of various stakeholders is changing esp the role of women in the management of Sacred groves has dwindled. The breakdown of ‘ancient joint family systems’ like ‘tharavadu’ has adversely affected the number of sacred groves in the state. The existence of 15, 000 sacred groves in the erstwhile state of Travancore was recorded in 1927 whereas current estimates account for not beyond 2000 sacred groves. As the number of stakeholders reduced, the community involvement in the management of sacred groves has also diminished over time. This paper studies the differential management dynamics in the sacred groves of Kerala, India using case studies of two sacred groves. It analyses how different stakeholders interact with each other using ethnographic methods. The paper argues that management practices of sacred groves should be more inclusive and should promote inter-generational dialogue.
Incentive program towards sustainability of organic rice certification in Limapuluh Kota Regency, West Sumatra, Indonesia
Authors: Mutiara V I , Hariance R , Utami A S
Published: May 2021

The government of Indonesia has committed to support the development of organic agriculture in Indonesia by establishing regulations on Organic Agriculture Systems in 2013. West Sumatra is one of the provinces in Indonesia which is very committed to developing organic agriculture. Before the decree was established, The Department of Agriculture of West Sumatra has allocated on Regional Budget year 2011 to improve the Organic Food Product Incentive by giving an incentive for 250 IDR per kilogram of organic rice. It was expected that it can influence farmers’ decision to recertify their organic products. Unfortunately, the incentive program was not continued in 2015. This research aimed to analyze the impact of government incentives on the sustainability of organic rice farming. The research was conducted in Limapuluh Kota Regency using survey methods. 65 organic rice farmers were interviewed. The research result showed that 80% of respondents agree that organic certification is a benefit for them. 20% of respondents do not think that organic certification is a benefit for their organic rice. As a result, they do not use the incentives for the benefit of organic rice production and organic recertification. 60% of them use it for household needs. Although the incentive program is not continued, 70% of farmers recertify their organic rice with the main reason is that it was the group’s decision. It is suggested that farmer’s motivation to re-certify organic rice should be become a consideration by the government for the development of organic rice farming programs.
Sustainable transition, transformation, and disruption in agroecology
Authors: Joy Rosewine
Published: May 2021

Agroecological systems are increasingly becoming volatile with climatic changes and development pressures, uncertain productivity, management complexity, ambiguous sustainability approaches. With this background, the main aim of this conceptual paper is to identify various transitions, transformations, and disruptions in the agroecological space for food production. The review identifies these discourses as a flow concept related and translucent. Agroecology case studies from across the world are analyzed to identify the approaches as transitional, transformational, and disruptive and to compare the sustainable strategies adopted in each approach. The study points out that differential approaches could lead to sustainable food production in a VUCA world.
Analysis of changes in coral trout (Plectropomus leopardus) morphology and tissue after exposure to clove oil
Authors: Rahim Sri Wahyuni , Yaqin Khusnul , Fachruddin Liestiaty , Kudsiah Hadiratul
Published: May 2021

Clove oil has been shown to be effective as an alternative to cyanide in the catching of groupers on coral reefs. However, it is necessary to analyze the quality of fish after exposure prior to application in the field. The aim of this study was to analyze changes in morphology and tissues of the eyes, gills and liver of coral trout (Plectropomus leopardus) after exposure to clove oil. Experiments were conducted in an aquarium measuring 1.0 mx 0.5 m x 1.0 m filled with seawater. The fish were sprayed with several concentrations of clove oil (20, 30, 40, 50, 60 ppm) until stunned, then transferred into the tank for observation of external morphology and fish tissue. The results showed that exposure to clove oil at concentrations of 20-60 ppm had no effect on coral trout external morphology (eyes, skin, scales, fins and gill covers). Histologically, small changes were observed in the eye, gill and liver tissues starting at a concentration of 30 ppm. This study showed that exposure to clove oil at a concentrations of 20 ppm did not appear to have harmful effects on coral trout (Plectropomus leopardus).
A review of the known distribution of Halophila spinulosa in Indonesia with herbarium from Laikang in South Sulawesi
Authors: Yasir I , Moore A M
Published: May 2021

Seagrasses are true plants living in the marine realm. The Coral Triangle is also the centre of seagrass diversity with 14 species recorded in Indonesian waters. There is a growing awareness of the ecological and socio-economic importance of seagrass meadows as well as the growing threats to these valuable coastal ecosystems. However, there is a lack of accessible data on seagrass distribution at ecosystem and species scales. The most speciose seagrass genus is Halophila, with at least 7 species (Halophila beccarii, H. decipiens, H. major, H. minor, H. ovalis, H. sulawesii and H. spinulosa) known to occur in Indonesia. Reported from Malaysia to eastern Australia, Halophila spinulosa is a data deficient tropical seagrass. We review the known distribution of H. spinulosa based on a search of Indonesian and international literature. We also present an annotated herbarium of H. spinulosa samples collected from Laikang in South Sulawesi, Indonesia. Samples were collected in September 2020 at low tide at depths of around 0.75 to 1.25 m on a silty sand substrate along with samples of other seagrass species present. Herbarium specimens were cleaned of epiphytes and sand. The samples were laid out carefully on A4 paper, arranged so that all parts were clearly visible, covered with gauze, and placed on folded newspaper. The prepared samples were then sandwiched between piles of newspaper and placed in a wooden press. The herbarium specimens will be preserved in the Marine Biology Laboratory collection, Marine Science Department, Universitas Hasanuddin. We consider the distribution data for H spinulosa are far from complete; this review and herbarium should inform and spur further research on this species and it’s distribution at macro (site) and micro (within site) scales.
Preliminary assessment of Tripneustes gratilla populations in Seagrass Beds of the Spermonde Archipelago, South Sulawesi, Indonesia
Authors: Tamti Hartati , Rappe Rohani Ambo , Andy Omar Sharifuddin Bin , Budimawan
Published: May 2021

Many sea urchins, including the collector urchin Tripneustes gratilla, are well known for their role as herbivores, contributing to the control of fast growing macroalgae that can potentially overgrow and dominate seagrass beds and reef flats. Tripneustes gratilla is a short-spined sea urchin that can be easily found and collected by hand from the seagrass meadows which are their main habitat, especially during low tide. The exploitation of this species in Indonesia began to expand several years ago when the demand for T. gratilla gonads started to rise, for both commercial purposes and household consumption. This study aimed to determine the population and distribution of T. gratilla in seagrass ecosystems with different conditions across the Spermonde Archipelago, South Sulawesi, Indonesia. The results indicate that T. gratilla population abundance and size distribution are affected by several factors: seagrass condition, water quality, and the intensity of sea urchin collection. The results also emphasize the urgent need for developing and implementing effective management to ensure the sustainability of this important sea urchin species.
Development of a benthic spatial ratio index as an indicator of small island deformation
Authors: Selamat M B , Lanuru M , Mashoreng S , Amri K , Idrus M R
Published: May 2021

The ability of coral reefs and seagrass beds to reduce wave energy positions these ecosystems as the most reliable natural protection for many small islands, especially for coral islands and atolls. With coral damage reaching 174 hectares per year, there must be changes in the spatial composition of coral reefs and seagrass beds around many small islands in the Spermonde Archipelago, changing the shape of the islands and reducing the quality of life of their inhabitants. This study aimed to map the spatial composition of benthic substrates (coral reefs, seagrass beds, and macroalgae) around small islands over time, and to relate changes in substrate composition to island shape change. The initial study was conducted at Barrangcaddi island from July to December 2018. Three field surveys collected spatial data on benthic substrates (coral, seagrass, macroalgae), bathymetry, waves, tides, and beach profiles. The satellite data used were Sentinel 2 images from 2015 to 2018. Satellite image processing included atmospheric correction using the DOS method, land masking, geomorphic segmentation, and classification using the maximum likelihood, Self Organizing Map and Segmentation methods. Thirteen benthic substrate classes were validated with thematic accuracy ranging from 86% to 95%. The land area of Barrangcaddi Island changed around 6 percent from 2015 to 2018. The benthic spatial ratio index for Barrangcaddi Island shows that the north side of the island was the most vulnerable to coastal abrasion, and the existing benthic substrate is no longer effective in reducing the wave energy that hits the island from this side.
Impact of increasing sea surface temperature on skipjack tuna habitat in the Flores Sea, Indonesia
Authors: Putri Andi Rani Sahni , Zainuddin Mukti , Musbir Musbir , Mustapha Muzzneena Ahmad , Hidayat Rachmat , Putri Rini Sahni
Published: May 2021

The Flores Sea is a water mass transfer route from two large oceans, namely the Pacific Ocean to the Indian Ocean known as Indonesian Throughflow (ITF). This flow certainly has an impact on the waters it passes through, including the Flores Sea, making the Flores Sea a hotspot for changes in oceanographic conditions. This study used satellite data to determine the increase in Sea Surface Temperature (SST) in the Flores Sea during 2015-2019. It used the Generalized Additive Model (GAM) analysis to analyze the effect of increasing SST on skipjack tuna habitat in the Flores Sea. The results showed that there had been an increase in SST of up to 2.5 °C over the past five 15 years in the Flores Sea. This increase has affected pelagic fish habitat in these waters. This increase in SST affects the tuna skipjack habitat, as evidenced by the decrease in catches in areas with warmer temperatures than usual. This study is important in considering the sustainable management of tuna fisheries, especially in tropical waters.
The surface wind regimes on the northeast coastal of Kalimantan during 2016-2018
Authors: Roem Muhamad , Musa Muhammad , Rudianto  , Risjani Yenny
Published: May 2021

This research aims to investigate the wind patterns in Northeast coastal of Kalimantan Island, known to border the western part of the Sulawesi Sea. Furthermore, the temporal wind patterns were examined based on the 2016-2018 recording data on Tarakan Island. The distribution of wind direction as well as speed were further analysed to obtain the monthly and seasonal wind pattern. The results show pattern complexity in the research area indicated by shifting in the monthly and seasonal wind resultant. This shift is particularly from the north, on instances where the Asian Monsoon is active, and conversely from the south at the Australian Monsoon peak. Meanwhile, during the transition period between monsoons, the wind blows weakly from various directions. However, the monsoon index value does not meet the criteria for the monsoon wind due to the influence of the sea breeze from the Sulawesi Sea throughout the year. Further analysis shows that the complexity of the local wind pattern is formed by sea breeze which is intertwined with monsoon winds.
Changes in seagrass carbon stock: implications of decreasing area and percentage cover of seagrass beds in Barranglompo Island, Spermonde archipelago, South Sulawesi, Indonesia
Authors: Mashoreng S , Nafie Y A La , Selamat B , Isyrini R , Amri K
Published: May 2021

Seagrass ecosystems in shallow waters, including in highly dense small islands, are vulnerable to anthropogenic activities and may lead to a decreasing in seagrass area and percentage cover. As a result, it will negatively affect climate change mitigation, i.e. a decrease in seagrass carbon stock. This research was conducted to evaluate seagrass carbon stock changes in Barranglompo Island, Spermonde archipelago, in 2001 and 2017. Carbon stock estimation was carried out by collecting seagrass biomass based on the category of a sparse, medium, and dense seagrass coverage (each with 20 replications) and analysing their carbon concentrations. Changes in carbon sequestration were analysed using an estimated approach to the changes in the seagrass bed areas. Landsat and Worldview-2 image analysis were utilized to estimate the area of seagrass beds in 2001 and 2017, respectively. Results showed a decrease in seagrass beds by 9.9 ha, from 66.8 ha in 2001 to 56.9 ha in 2017, or an average of 0.62 ha per year. Based on that, it was estimated that seagrass carbon stocks had declined from 74.19 tons in 2001 to 65.21 tons in 2017 or decreased by an average of 0.75% per year. Anthropogenic activities, such as boat anchors as well as household waste disposal in the seagrass area, are considered having the potential in causing a decrease in seagrass area and the percentage coverage.
The development of Indonesian seaweed based on innovation cluster model
Authors: Sumule Ophirtus , Angkasa Wisman I , Retno Herni Widya , Andiewati Suci
Published: May 2021

In 2018, Indonesian production of the seaweeds Eucheuma cottonii and Gracilaria sp. reached 11.08 million tons and 1.55 million tons, respectively. However, the economic value obtained is low, as 85% of the production is still exported as a raw material. The remainder is exported as semi-refined materials, i.e. ATC chips and semi refined carrageenan (SRC), with very little refined carrageenan. There are no companies processing seaweed into end products where seaweed is the main raw material, such as in the food industry, pharmaceuticals, cosmetics, etc. The supply chain from upstream (aquaculture) to intermediate (intermediate products) and downstream industries is not efficient in Indonesia, because almost all intermediate and downstream industries are concentrated in big cities like Jakarta and Surabaya while the bulk of the upstream industry is spread across large expanses of eastern Indonesia. As a result, the bargaining position for upstream products produced by farmers is weak. All of these problems are expected to be minimized by referring to a holistic work plan through Seaweed Innovation Clusters, enhancing communication and collaborative collaboration of Quadruple-Helix ABGC (Academic, Business, Government and Community) and other supporting elements as the main pillar of the innovation cluster. With this synergy, added value, and business continuity, the role of seaweed in raising regional competitiveness can be improved.
High salinity effect on mortality of sandfish Holothuria scabra (Jaeger, 1833)
Authors: Tuwo A , Yasir I , Bestari A D , Yanti A , Aprianto R , Tresnati J
Published: May 2021

The sandfish Holothuria scabra is a sea cucumber with a very high economic value. Sandfish cultivated in brackish water ponds will face a high salinity problem in the dry season. This study aimed to analyse the effect of high salinity on sandfish mortality. The study was done in a controlled tank in which the sea water was allowed to evaporate naturally, without the addition fresh water, so that the salinity increased continually. High salinity can cause injury and death to sandfish; before death, there was an evisceration. The death salinity of sandfish was 47 ppt. Sandfish have a greater range of tolerance to salinity than other sea cucumber species.
Survival rate of brown-marbled grouper Epinephelus fuscoguttatus cultured with seaweed Gracilaria changii in multitrophic microcosm models
Authors: Yasir I , Tresnati J , Aprianto R , Tuwo A
Published: May 2021

Groupers (Epinephelus) are economically important fish.Gracilaria changiiis a red alga with a high economic value that is widely cultivated in brackish water ponds. In this study,Epinephelus fuscoguttatusandG. changiiwere polycultured in a multitrophic microcosm model. This study aimed to evaluate the possibility of these two species being cultured multitrophically. In this study we analysed the survival rate of groupers under two seaweed cultivation models (a bottom method and floating method). A control microcosm had no seaweed (grouper monoculture). Fish weight used in the treatment was 135.94 to 359.36 g. The study lasts 47 days at the controlled indoor tanks. The survival rate is lower than the results in previous studies. The condition of water quality parameters was quite good during the treatment, except for ammonia and phosphate. The high ammonia and phosphate content is thought to be the cause of the low survival rate. The survival rate ranges from 47-87%.
Amino acid, nutrient digestibility and FCR of juvenile vannamei shrimp (Litopenaeus Vannamei) at various dosage tofu waste using mixed organism in feed
Authors: Surianti  , Aslamyah Siti , Tandipayuk Haryati
Published: May 2021

Tofu dregs are industrial waste that can be used as a source of carbohydrates. However, its use in feed formulations is limited because it contains high crude fiber and low quality. The fermentation process uses a mix of microorganisms. proven to improve the nutritional quality of tofu pulp. This study ams to determine the dosage of fermented tofu pulp in feed against feed amino acids, nutrient digestibility and juvenile food conversion ratio (FCR) of vaname shrimp. The study was designed in a completely randomized design with treatment of 4 doses of fermented tofu pulp in the feed, namely 5, 10, 15 and 20%. The feed was given as much as 10% of total body weight/day to juvenile vaname shrimp measuring 0.5 g per individual kept in a glass aquarium with 20ppt media passage for 60 days. Amino acid measurement results are within the range sufficient for the needs of vaname shrimp. Analysis of variance showed that treatment had a significant effect on total digestibility, protein, crude fiber, carbohydrates and fat, but not on FCR. The highest yield was shown at a dose of 15% protein digestibility (85.62±1.576), crude fiber (87.30±1.117), carbohydrates (90.67±1.231) and a dose of 20% fat digestibility (98.75 ± 0.070) and total digestibility ( 79.70±0.222), the FCR ranges (3.237±.0.35) to (4.141±.0.64). The dosage of fermented tofu dregs with mixed microorganisms can be used 15% in the feed formulation.
Antioxidant activity of methanolic extract of Eucheuma spinosum extracted using a microwave
Authors: Rismayanti Ni Luh Putu Mita , Husni Amir
Published: May 2021

Eucheuma spinosum is a widely cultivated red seaweed. The phenolic compounds contained in E. spinosum, especially flavonoids, can be used as a source of natural antioxidants. This study aimed to determine the antioxidant activity of E. spinosum extracted using a microwave with different extraction times (6, 8 and 10 minutes). The parameters measured included yield, phytochemical test, total phenolic content, total flavonoid content and antioxidant activityt, namely 2,2 diphenyl-1-picrihydrazyl (DPPH) and ferric reducing antioxidant power (FRAP). The results showed that the E. spinosum extract with an extraction time of 10 minutes had the highest yield with a total phenolic content of 59.42 ± 27.36 mg GAE/g and a total flavonoid content of 65.48 ± 25.34 mg QE/g. The results of phytochemical screening showed that the extract contain triterpenoid compounds. The antioxidant activity of the E. spinosum extract showed the highest IC50 value of 46.52 ± 5.53 ppm using the DPPH method and the FRAP method was 58.92 ± 1.76 μM/g.