Uniformity Index Values Research Articles

A CFD‐based manifold design methodology for large‐scale PEM fuel cell stacks

AbstractThe flow distribution issue is of significance to the fuel cell stack performance and durability, which herein is studied from a theoretical and practical level. The manifold flow fundamentals are clarified and the pressure‐reconstruction‐based principle to regulate flow distribution is revealed. The prerequisite and corequisite lie in the ratio of pressure drop between headers and the entire manifold, and the pressure recovery in the inlet header. Accordingly, a step‐by‐step manifold design methodology is proposed and further quantified by detailed and organized simulations. A desirable effect on flow uniformity is validated in large‐scale stacks consisting of 300 and 400 cells, and the values of flow uniformity index represented by coefficient of variation (CV) are 3.32% and 2.95%, respectively. Moreover, a novel wedge‐shaped layout of the intake header is proposed for further optimization. The corresponding CV values have notably declined to 1.36% and 1.29%, nearly 60% lower than the conventional rectangular counterparts.

Community Structure of Sea Urchins (Echinoidea) in the Intertidal Zone of Thomas Beach, Uluwatu

Thomas Beach, located in Uluwatu, Province of Bali, is a rocky shore inhabited by sea urchins. The research aims to discover the habitat characteristics and community structure of sea urchins (Echinoidea) in the intertidal zone of Thomas Beach. Data collection was conducted from April to May 2023 during the lowest tide. A quantitative method with modified line transects was used for data collection. Data collected included the number and species of sea urchins, water quality parameters (temperature, salinity, pH, dissolved oxygen, water clarity, and depth), and substrate types. Data were analyzed using Microsoft Excel, including individual density, diversity index, uniformity index, and dominance index. The research findings revealed five species of sea urchins: Echinotrix calamaris, Echinometra oblonga, Echinometra mathaei, Tripneustes gratilla, and Stomopneustes variolaris. The highest density of sea urchins was found in E. oblonga (16.91 ind/m2). The diversity index values ranged from 0.4936 to 0.8721, indicating a low level of diversity. The uniformity index values ranged from 0.4493 to 0.784, suggesting the community is relatively unstable. The dominance index values ranged from 0.5036 to 0.7166, indicating a moderate level of dominance. The aquatic habitat characteristics, based on the research findings, it was determined that a temperature of 30℃, salinity ranging from 31.77 to 32.76, pH of 8, dissolved oxygen (DO) of 5 mg/l, water clarity of 100%, and a depth ranging from 8.4 to 33.93 cm. The substrate type was rocky at station 1, sandy with seagrass at station 2, and rocky sandy at station 3.

Macrozoobenthos Community Structure at Teluk Marunggai Beach, Nagari Sungai Nyalo, Pesisir Selatan District, West Sumatera Province

Teluk Marunggai Beach, Nagari Sungai Nyalo, is one of the new tourist areas in Pesisir Selatan Regency which, over time, will begin to be in demand by tourists, which will have an impact on the life of the biota on the beach, one of which is macrozoobenthos. This research was conducted in March 2023 in the Intertidal Zone of Teluk Marunggai Beach, Sungai Nyalo Village, Koto Ampek Tarusan District, Pesisir Selatan Regency, West Sumatra Province. The purpose of this study was to determine the type and abundance of macrozoobenthos species in the coastal waters of Marunggai Bay and to determine the diversity, uniformity, dominance and distribution patterns of macrozoobenthos in the coastal waters of Marunggai Bay. The research method used is the survey method, where the sampling using the quadrant transect method is carried out at three stations. The research results found 40 species of macrozoobenthos. The most common species found at all stations were Turbo cinereus from the Turbinidae family and the Gastropod class. The macrozoobenthos abundance values ​​obtained ranged from 6.44–6.67 ind/m2. Species diversity index values ​​ranged from 3.06–3.52, namely high. Uniformity index values ​​ranged from 3.02 to 3.14, high uniformity, dominance index values ​​ranged from 0.10 to 0.15; no species dominated, and the value of the distribution pattern ranged from 2.959 to 2.962 with a group distribution pattern

MACROZOOBENTHOS COMMUNITY STRUCTURE IN THE INTERTIDAL ZONE OF MUARA AIR HAJI VILLAGE PESISIR SELATAN REGENCY WEST SUMATERA PROVINCE

Muara Air Haji Village is a coastal area with various anthropogenic activities that can disrupt the aquatic ecology, especially in the intertidal zone. Biological indicators such as macrozoobenthos are needed to provide a correct and sustainable picture of water quality. This research uses a survey method to determine macrozoobenthos' type, abundance, diversity, uniformity, dominance, and distribution pattern in the intertidal zone. Sampling was carried out using three stations, and each station consisted of three transects and three subzones comprised of the upper, middle, and lower intertidal zones using a quadrant plot measuring 1 x 1 m. The results of this research found three classes of macrozoobenthos with five species. Abundance values ​​at each station ranged from 0.89–4.56 ind/m2, while abundance in the intertidal subzone ranged from 1.11–3.56 ind/m2. The diversity index (H') at stations I and III is 1.93 and 1.17, which means it is included in the medium diversity category, while the diversity index (H') at station II is 0.84, which means it is included in the low category, moderate distribution of individuals or non-uniform number of individuals, moderate ecological pressure and moderately polluted water stability. The uniformity index value ranges from 0.65–0.99, which means the uniformity category is balanced. At station II, macrozoobenton dominates with an index value of 0.62, while stations I and III have no dominant species with index values ​​of 0.30 and 0.45. The distribution pattern (Id) of macrozoobenthos is clustered with a value of 3.45–4.18

Reef fish community structure in the waters of small islands Central Bangka Regency

This study aimed to analyze the community structure of reef fish in the small island waters of Central Bangka. The research was conducted in March 2022 in the waters of Bebuar Island, Ketugar Island, Ketawai Island, and Gusung Asam Central Bangka Regency, Bangka Belitung Islands Province. The coral reef survey method uses purposive sampling and the coral reef fish visual census with data analysis of abundance, diversity index, uniformity, and dominance. In-site water quality measurements included six parameters: temperature, salinity, current, brightness, depth, and pH. The results showed that coral reef cover from 44.60 - 87.00% with the medium to very good category. The abundance of reef fish from 1 to 3 individuals/m2 was dominated by 18 species of the Pomacentridae family. The reef fish diversity index ranged from 2.47 to 2.90, including the medium category. The uniformity index value ranged from 0.79 - 0.94, including the high category, indicating that the species found were evenly distributed across all stations. The dominance index value ranges from 0.07 to 0.15, including low, where no species dominates significantly and the fish are evenly distributed. Temperature, brightness, pH, and salinity are factors that support the growth of coral and reef fish. A water current speed of 0.05 – 0.20 m/s is quite helpful in cleaning coral reefs from mud and can supply oxygen. Water conditions were categorized as good and fulfilled the seawater quality standards.

Evaluation of Rock and Explosive Properties for Fragmentation Characterization: An Application of WipFrag

This study investigates the rock explosive properties in selected Lokoja quarries, Nigeria, with the goal of characterizing fragmentation for optimized downstream operations. The analysis includes porosity, UCS values, and permeability assessment in Gitto quarry, highlighting advantages in material application. Comparisons between rock formations (Q1 and Q2) reveal varying compressive strengths, crucial for determining appropriate explosive energy for efficient fragmentation. Blast design parameters from Q1 and Q2 indicate consistent values, aiding in operational planning. Fragmentation analysis, conducted using WipFrag software, delineates size ranges and classifies the blast as having a moderate distribution. Correlations between blast fragmentation size and powder factor underscore the impact on efficiency. A classification chart and table are presented for convenient interpretation of results, providing valuable insights for enhancing blasting practices in Lokoja quarries and ultimately improving productivity. The fragmentation analysis result carried out in this study using WipFrag software shows that the 50%, 80% and Maximum block size passing size ranges from 539.94 – 1349.53 mm, 690.07 – 1907.81 mm, 808-2280 mm respectively. The blast fragmentation sizes are classified as moderate distribution blast based on the uniformity index value ranging from 1.95 to 2.4. The relationship between blast fragmentation size and powder factor was evaluated using linear correlation coefficient. It was noted that, X20, X50, X80 has high R2 values greater than 60% respectively

Gastropod Community Structure in the Mangrove Area, Kuala Batee District, Southwest Aceh District

This research was conducted to determine the types of gastropods and the structure of the gastropod community in the Mangrove area of Kuala Batee District, Southwest Aceh Regency. The quantitative descriptive method is used to determine research stations using purposive sampling techniques. Gastropod sampling was carried out at three station locations, each station consisting of three sub-stations with a size of 10 x 10 m. In the substations, 15 transects measured 1 x 1 m, namely, two points at the corner of each transect and one point in the middle. The results of the research showed that the gastropods found were 11 species from 4 ordo, ordo Archaeogastropoda consists of Neritina turita, N.semiconica, N.variegate, Neritodryas dubia, and Clithon corona, ordo Ceanogastropoda consists of Faunus ater and Bitium munitum, ordo Mesogastropoda consists of Cerithidea optusa, Stenomelania plicaria, and Thiara scabra, ordo Ellobiida consist of Cassidula angulifera. The structure of the gastropod community in the mangrove area of Kuala Batee District, Southwest Aceh Regency, has a diversity index ranging from 0.65-1.32, including the medium category, uniformity index values ranging from 0.36-0.63 including the medium category, and dominance values ranging from between 0.33-0.63 is included in the medium category. Environmental parameters in the mangrove area show an average temperature value of 28.20C, a salinity value of 5.6 ppt, and a pH value of 8.3

Study of the development of milkfish (Chanos-chanos sp.) cultivation based on plankton aspects

Background: Mandalle Beach, Pangkep Regency, is located in a coastal area with areas consisting of beaches, river estuaries, mangrove forests, rice fields, ponds, and residential areas. This area has potential for fish cultivation, especially milkfish cultivation. To support data and information about the prospects for cultivating milkfish in this region, a study was carried out on biological aspects, especially plankton. Materials and Methods: The research was carried out at five research locations, namely: location 1 is on the coast, which borders the coast of Barru Regency; location 2 is the location around the Pangkep State Agricultural Polytechnic Campus Pier; location 3 is on the beach, where mangrove vegetation grows around it; location 4, namely at the mouth of the river, which borders Mandalle Village and Tamarupa Village; and location 5, namely in the part adjacent to the rice fields and ponds of Mandalle Village. The plankton parameters tested were plankton abundance, variety, and dominance. The data obtained was then processed and analyzed using descriptive analysis. The plankton parameters tested were abundance, uniformity, diversity, and plankton dominance. The data obtained was then processed and analyzed using descriptive analysis. Results: The results showed that plankton abundance (cells/ml) was in the range of 250–300 cells/ml. Each research location has different types of plankton, which have the highest abundance. The plankton uniformity index value is in the range of 0.18108–0.22653, with the highest uniformity value occurring at location 2 and the lowest at location 3. The types of plankton that dominate in each research location are Chaetoceros sp., Gyrodinium sp., Thallasionema sp., Gymnodinium, and Cosconodiscus, but the most dominant type of plankton in all research locations is Chaetoceros sp., namely 0.461538462. Conclusions: Based on the study of the type, abundance, diversity, uniformity, and dominance of plankton, it can be stated that, based on the plankton aspect, the waters of Mandalle Beach, Pangkep Regency, are suitable and meet the requirements for cultivating milkfish; however, due to the large number of fishing activities and the proximity of residential areas and rice fields, the cultivation technique What is recommended is traditional or semi-intensive milkfish cultivation.

Experimental investigation of radio frequency heating uniformity of wheat flour surrounded by deionized water and NaCl solution

The present study proposes an approach to overcome the problem of corner/edge overheating of foods undergoing radio frequency heating. For testing, a container with a central rectangular compartment surrounded by a frame of four compartments was used. Wheat flour, a representative of low-moisture foods, was packed inside the rectangular compartment to provide a density of 800 kg/m3. Afterwards, in the surrounding compartments, air, deionized water and NaCl solution were used for independent radio frequency heating tests. Two different electrode gaps (135 and 145 mm) were employed. The temperature of the sample was measured continuously using fibre optic probes at four different internal locations. The difference between the maximum and the minimum temperatures for three different cases (a: air, b: deionized water and c: NaCl solution) were as follows for electrode gaps of 135 and 145 mm, respectively: (a) 27.3 and 26.1 °C, (b) 2.5 and 4.8 °C and (c) 3.7 and 1.8 °C. Uniformity index values were also calculated. The results showed that temperature variation within the sample was greatly reduced when the sample was surrounded by deionized water or NaCl solution. PRACTICAL APPLICATION The project findings will provide processors with a practical means to achieve more uniform radio frequency heating of low-moisture foods.

Diversity of Gastropods and Bivalvia in Jukung Bay Waters, Pemongkong Village, Jerowaru District, East Lombok Regency

Several activities affect the distribution of gastropods and bivalves, one of which is the activity of the community around the coast which is thought to affect water quality. The entry of organic and inorganic contaminants into coastal waters is thought to cause a decrease in water quality followed by changes in physics, chemistry and biology. The purpose of this study was to determine the diversity of gastropods and bivalves in the waters of Jukung Bay, Ujung Betok Hamlet, Pemongkong Village, Jerowaru District, East Lombok Regency. This research was conducted in Ujung Betok Hamlet (Tukung Bay Waters), Pemongkong Village, Jerowaru District, East Lombok Regency. the study was conducted from October 2022 to July 2023. The results showed that the highest species abundance was found in the Gastropoda class Nassarius sp with an abundance of 31 individuals/m2. The highest gastropod and bivalves diversity index value was obtained at point 3, namely 0.42 individuals/m2. The highest gastropod and bivalves uniformity index value was obtained at point 2 with a uniformity index value of 0.28. The dominance index value obtained was 0.1-0.56 individuals/m2 included in the moderate dominance category. Based on the results and discussion it is known that the abundance of gastropods and bivalves in the coastal waters of Jukung Bay which were analyzed totaled 108 individuals. The diversity index (H') obtained in this study ranged from 0.41-1.39 individuals/m2. The uniformity found ranged from 0.14 to 0.28 individuals/m2. The dominance index obtained ranged from 0.1 to 0.56 individuals/m2.

BIODIVERSITY AND ABUNDANCE OF PHYTOPLANKTON IN RICE-FISH FARMING SYSTEM

Rice-fish farming system that is purposed to maximize land use by adding fish farming to its systems. In the Rice-fish farming system, the fish farm serves as a solution to overcome pests so it can provide benefits for the farmers. Fish farm maintenance is considered to be a solution to reduce farmers expenditures in the use of fertilizers. The reason is in the fish-maintaining process, fish will naturally excrete dirt which has a function as organic fertilizer which will increase the fertility of the waters. The purpose of this study was to determine the composition of phytoplankton as well as the physical and chemical quality of the water in several Rice-fish farming system stations in Panembangan Village so that the condition of the ecosystem can be detected whether it is in good or bad condition. The Results showed that the diversity index value ranged from 0.61-1.99. The uniformity index value was obtained in the range of 0.15 – 0.50 and the dominance index value was obtained in the range of 0.20 – 0.72. While, the four stations still have good water quality, the conditions in the Rice-fish farming system area of Panembangan Village are still suitable for the growth of organisms.

Community Structure of Phytoplankton in The Bongkok River of Kubu Raya Regency, West Kalimantan

Located around the Mangrove Production and Protection Forest in Tanjung Harapan Village, Kubu Raya Regency, the Bongkok River quality needs to be studied to determine the quality of the river. This study aims to determine the physicochemical quality of water and the community structure of phytoplankton in the Bongkok River during the dry and rainy seasons. The survey method was used at three stations and 9 observation points in both seasons. Phytoplankton types are identified up to the species level. The physicochemical factors observed included temperature, transparency, water flow, pH, salinity, dissolved oxygen, dissolved carbon dioxide, and levels of nitrate and phosphate. The community structure is seen from the abundance, diversity, uniformity, and dominance index values. From a physicochemical perspective, the Bongkok River is a brackish water type with relatively low levels of phosphate and nitrate nutrients and high dissolved CO2, but dissolved oxygen is still good enough to support aquatic life. There are 41 phytoplankton species from 6 classes, including Bacillariophyceae, Chlorophyceae, Cyanophyceae, Dinophyceae, Euglenaphyceae, and Xanthophyceae. The phytoplankton abundance in the dry season is higher than in the rainy season but is still at a low to moderate level. The phytoplankton diversity in the Bongkok River is in the medium category (2.46 – 2.67) but has a high evenness (0.72-0.89) and low dominance (0.11-0.18). Overall, the water conditions in the Bongkok River are sufficient to support the life of aquatic biota. However, the abundance of phytoplankton is still at a low to moderate level, especially during the rainy season.

Macrozoobenthos Diversity as A Bioindicator of Water Quality in River Sesaot Village Narmada West Lombok

Sesaot River is a river located in Narmada, West Lombok. The Sesaot River has been widely used by the surrounding community for their agricultural, plantation and daily activities. The high activity of the people around the river causes a decrease in the quality of river water. Macrozoobenthos is a bioindicator that can be used to describe a water's air quality. The purpose of this research is to examine the water quality of the Sesaot River utilizing macrozoobenthos as a bioindicator. The study was carried out at three different locations along the Sesaot River: upstream, middle, and downstream. At each observation site, macrozoobenthos ecological study and measurements of river water physical and chemical parameters were performed. According to observations, the pH, DO, and TDS of river water remain within the range of acceptable environmental quality standards. The macrozoobenthos found in the Sesaot Narmada river consist of 3 classes, 8 families and 8 species. Gastropoda, Mollusca, and Insecta are the third class discovered. The macrozoobenthic diversity index values discovered ranged from 0.8 to 1.35. Based on these findings, the macrozoobenthos diversity at the three locations is low. The uniformity index values obtained at the three stations ranged from 0.03 to 0.07, indicating that the distribution of individuals was unequal and unbalanced. At the three stations, the dominance index ranged from 0.27 to 0.55. Based on the findings, it is possible to conclude that the water quality of the Sesaot Narmada river is moderately to badly polluted.

Species Diversity of Gastropoda in Seagrass Ecosystems at Mandalika Beach

Madak is looking for or hunting marine biota that can be consumed or has high economic value. Madak's activities can still threaten the existence of species on Mandalika Beach, one of which is Gastropods. This research focuses on the diversity of gastropod species that live in seagrass beds at Mandalika Beach. This study aims to identify the abundance and analyze the diversity index, uniformity index and dominance index of gastropod species in seagrass ecosystems on the Mandalika coast. This type of research is included in the type of descriptive-explorative research. This study describes the diversity of gastropod species in seagrass ecosystems on Mandalika Beach. The testing procedure utilized purposive examining. The research was conducted at 3 stations with 3 transects at each station. The results showed 27 species and 15 families of Gastropods. The species abundance value was 0.796 ind/m2, the species diversity index value was 1.849, the uniformity index value was 0.686, and the dominance index value was 0.280.

Struktur Komunitas Makroalga di Pantai Pandawa, Bali

Macroalgae are classified as low-level plants (thallophyta), no have vascular and have a vegetative body that has not recognized the differentiation of the roots, stems and leaves, so it is called a thallus. This aims to determine the diversity of macroalgae species and the percentage of maroalgae cover in the waters of Pandawa Beach. The research was conducted for 2 months from January-February 2021. This study used a descriptive method with a quantitative approach. The data were collected at 3 stations using the 1x1 m2 quadrant transect of method. The results of the study found 17 types of macroalgae on Pandawa Beach including Halimeda macroloba, Padina australis, Ulva lactuca, Palmaria palmata, Galaxaura rugosa, Laurencia papillosa, Gracilaria textorii, Turbinaria deccurrens, Halimeda opuntia, Kappaphycus alvarezii, Gracilariopsis longissimi, Chondrococcus hornemannii, Amphiroa fragilissima, Chondrus crispus, Halymenia floresii, Amphiroa rigida, and Phyllophora crispa. The highest abundance value of macroalgae species was Laurencia papillosa species with a total of 2,87 individuals/m2. Based on the results of the calculation of the diversity index value on Pandawa Beach is 1,44-2,02 so it is included in the medium category. The uniformity index value on Pandawa Beach is 0,69-0,87 so it is included in the medium category. The dominance index value on Pandawa Beach is classified as a low category with a value of 0,17-0,28. The highest percentage value of macroalgae cover on Pandawa Beach was Laurencia papillosa with 0,53-2,87%.

Effects of extraction techniques on textile properties of William banana peduncle fibers

In this research work, the effect of extraction methods on the physical (morphology, density, length, apparent diameter, and color) and mechanical (tensile and bending KAWABATA) properties of the William banana peduncle fibers were examined. Among the methods used to carry out those tests, can be cited; the extraction tests using water retting (WR), dew retting (DR), and rolling by mechanical extraction (ME). The mechanical tests were carried out using TEXTECHNO Vibromat ME (measurement of the vibration frequency of the fiber), tensile test (MTS 20/M), and a Bending KAWABATA KES-FB2-SH test. To analyze the microstructure of the longitudinal plane of William banana peduncle, Scanning Electron Microscopy (SEM) mapping was used. The results showed that, water retting, gave a high yield (42.55%) compared to fibers extracted by rolling (23.40%). The different methods of extraction by retting lead to a reduction of about 35% in the apparent diameter of the fibers compared to the fibers obtained mechanically. When studying the colors of the surfaces of the fiber, the results presented the fact that the fibers extracted by rolling (ME) were darker than those retted in water or dew (WR and DR). However, the retted fibers were redder and yellower compared to the fibers passed through a rolling mill. SEM mapping was a result of strips of flat fiber bundles, followed by the brittle fracture surface regardless of the extraction method used. water retted fibres are longer than those extracted by rolling. There was a high uniformity index (UI) value for WR (70. 89%), which showed that these fiber bundles were more uniform in length compared to the two other methods (66.4% for DR and 64.28% for ME). The density of the William banana peduncle was not very sensitive to the extraction method. Significant differences were revealed for the specific breaking strength, initial modulus, and elongation at break depending on the extraction method. The Kawabata bending test showed the fact that fibers extracted by rolling were stiffer (1.63 mNmm2/tex2) compared to retting method fibers (0.51 mNmm2/tex2 for WR and 0.73 mNmm2/tex2 for DR). There is a possibility of using William banana fiber for textile applications in view of the tensile and bending properties obtained.

Seaweed diversity and community structure on the west coast of Aceh, Indonesia

Abstract. Erniati, Erlangga, Andika Y, Muliani. 2023. Seaweed diversity and community structure on the west coast of Aceh, Indonesia. Biodiversitas 24: 2189-2200. One of the commodities that continues to be developed by the Indonesian government in fisheries is seaweed. The potential of seaweed as a food ingredient in Aceh is very abundant. However, diversity and community structure of seaweeds on the west coast of Aceh have not been studied much. Therefore, this study has been carried out to assess the diversity and community structure of seaweeds on the west coast of Aceh based on transect method. Sampling has been carried out in all districts/cities (6 districts and 1 city) of west coast of Aceh. Altogether, a total of 50 species have been identified; of which, maximum number of species belongs to Phaeophyta (21 species) followed by Chlorophyta (16 species) and Rhodophyta (13 species). The estimated value of diversity (H'), uniformity (E), and dominance (D) index is 1.02, 0.50 and 0.51 respectively. Based on the univariate diversity indices analysis, it has been found that seaweed on the west coast of Aceh is in the moderate category. Furthermore, the water quality parameters revealed the existence of conducive environmental conditions for the growth and life of seaweed. So, it is proposed that use of appropriate seaweed culture techniques can be carried out on the west coast of Aceh to able to make Aceh a seaweed center in Indonesia.

An improved vacuum-steam pulsed blanching machine design and garlic scape blanching verified experiment

Vacuum-steam pulsed blanching (VSPB) is an emerging blanching method resulting in high efficiency and product quality. However, inconvenient loading, small loading capacity, uneven rinsing and imprecise control hinder its application in food industry. Therefore, the current work aimed to design a VSPB machine, including selection of components, building a control system and designing a steam nozzle in order to increase the load capacity and improve device control. For this purpose, a horizontal blanching chamber with internal nozzle was designed and optimized using CFD method. The vacuum chamber design required a more evenly distributed steam inlet. A water-sealing vacuum pump, a cooling device and a hardware system were developed. The distribution of steam released from the nozzle in the chamber was numerically investigated by solving the three-dimensional Reynolds-averaged Navier-Stokes equations, with a velocity uniformity index value of 0.448. The validation blanching test was conducted using garlic scape as the test material. The steam holding time and the number of cycles significantly affected (p < 0.05) the color of the garlic scapes. Peroxidase (POD) activity decreased with the increase of blanching cycles until the enzymes were completely inactivated. VSPB significantly decreased (p < 0.05) the lignin content of the garlic scapes. The findings indicate that the best results were obtained after 2 cycles of VSPB and steam holding time of 30 s. Industrial relevanceHot water and steam thermal blanching are the two most frequently used blanching methods in food processing. Generally, they are used as a pretreatment before drying, freezing or canning of different fruits and vegetables. In current work, an improved vacuum-steam pulsed blanching machine was designed and the validation blanching test with garlic scape as the material indicated that VSPB operation was effective in preventing the synthesis of lignification in garlic scapes. By considering enzyme inactivation, lignification, color, and other quality attributes, 2 cycles of VSPB and steam holding for 30 s were proposed as the optimal VSPB conditions.

Long-term assessments of cotton fiber quality in response to plant population density: Reconciling fiber quality and its temporal stability

Regulation of plant population density is crucial for optimizing cotton fiber quality. However, the relationship between plant density and fiber quality stability under contrasting climatic conditions remains unclear, and the compromise between fiber quality and temporal stability is unknown. In this study, based on a long-term field experiment with various plant densities (1.5–10.5 plants m–2) conducted from 2008 to 2021, cotton fiber quality variability, including fiber length, fiber strength, elongation, uniformity index, and micronaire, and their temporal stability, were evaluated. We determined the optimal plant density for cotton cultivation and elucidated the contributions of plant density and climatic conditions to the variability of cotton fiber quality and its temporal stability in China’s Yellow River Valley. The results revealed that cotton maintained its upper-intermediate quality throughout the study period, with fiber length, strength, elongation, uniformity index, and micronaire values ranging between 28.04 and 30.03 mm, 26.15–30.05 cN tex–1, 5.90–6.83%, 83.85–85.44%, and 4.24–5.14, respectively. An increase in plant density improved fiber quality but impaired temporal stability (P < 0.01), and slight increases in stability at lower plant densities resulted in substantially decreased probabilities of years with major declines in fiber quality class. Plant density and climatic conditions regulated the quality traits (23.5% and 69.3% of the explained variance, respectively), including fiber length, fiber strength, and micronaire, while climate was the most important factor (75.9% of the explained variance) in determining their temporal stability. Photosynthetically active radiation and maximum and mean temperature exhibited significant positive effects on fiber quality, whereas mean diurnal temperature range had the opposite effect. A plant density of 3.3–5.1 plants m–2 ensures the highest temporal stability of cotton fiber quality without declines in the fiber quality class. This study first provides insights into balancing cotton fiber quality and temporal stability through agronomic interventions, with implications for the quantitative prediction of future crop quality changes owing to climatic variation.

GASTROPOD COMMUNITY STRUCTURE IN THE INTERTIDAL ZONE OF PASUMPAHAN ISLAND, PADANG CITY, WEST SUMATRA PROVINCE

Pasumpahan Island is one of the islands located in West Sumatra Province which has various activities of daily life, especially in the intertidal zone; it is suspected that it can interfere with the existence of aquatic organisms one of which is gastropods. Studying the structure of gastropod communities in the intertidal zone is an interesting natural laboratory to study. This research was conducted from December 2021 to January 2022 on Pasumpahan Island Padang City West Sumatra Province. The purpose of this study was to determine the structure of the gastropod community which includes species, abundance, diversity, uniformity, dominance, and distribution pattern of gastropods. As supporting data in this study, several environmental parameters were also measured which included water quality, sediment type, and sediment organic matter content. The research method used is a survey method, where sampling using the quadrat transect method is carried out at 3 stations. Based on the results of the study found 13 species of gastropods. The most common species found at all stations was Pythia scarabaeus, where the gastropod abundance values obtained between stations ranged from 2,78 to 5,00 ind/m2. The value of the species diversity index ranged from 1,50 to 2,02, which was moderate, the uniformity index value ranged from 0,77 to 0,88, which was high uniformity, and the dominance index value ranged from 0,16 to 0,29, meaning that there were no species found dominates and the value of the distribution pattern ranges from 1,31 to 2,47 with a clustered distribution pattern