Length Frequency Distributions Research Articles

DINAMIKA POPULASI IKAN TONGKOL ABU-ABU (Thunnus tonggol) YANG DIDARATKAN DI PELABUHAN PERIKANAN NUSANTARA PEMANGKAT

Longtail tuna (Thunnus tonggol) is one of the types of catches landed at the Pemangkat Nusantara Fishing Port. This study aims to determine the frequency distribution of fish length, length and weight relationships, growth parameters, as well as mortality and exploitation rates. Analysis of population parameters using Stock Assessment Tools FISAT II software Ver. 1.2.2. This research was conducted from March to June 2023. The method used in sampling longtail tuna is systematic random sampling method. The results of the study of the population parameters of longtail tuna landed at PPN Pemangkat showed the frequency distribution of the length of the cagak obtained a minimum length of 37 cm and a maximum length of 72 cm. The equation of the relationship between length and weight of tuna is W = 0.0104x3.1258 with a coefficient of determination (R2) of 0.876. The growth pattern is positive allometric. The growth coefficient (K) was 0.40 per year with an asymptotic length (L∞) of 79.65 and an initial theoretical age (t0) of 225 per year. The total mortality rate (Z) was 1.05 per year, natural mortality (M) was 0.76 per year, capture mortality rate (F) was 0.29 per year and exploitation rate (E) was 0.28. This exploitation rate value has not exceeded the optimum exploitation value of 0.5.

Estimate of Growth Parameters of Penaeus kerathurus (Forskäl, 1775) (Crustacea, Penaeidae) in the Northern Adriatic Sea.

Crustacean fisheries are gaining prominence globally amid a decline in finfish stocks. Some decapod crustacean species have experienced increased landings in response to shifting market demands and environmental dynamics. Notably, the caramote prawn (Penaeus kerathurus-Forskål, 1775) in the northern Adriatic Sea, Geographical Sub Area (GSA) 17, has risen in both landings and economic importance in recent years. However, despite its significance, comprehensive information on fishery-dependent data, age, and growth in this region remains lacking. To address this gap, this study employs modal progression analysis and the ELEFAN approach, utilizing the "TropFishR" R package and newly developed functions, including bootstrapping procedures. These advancements aim to overcome issues identified in previous versions and enhance the accuracy and reliability of age and growth estimations. The study leverages one year of monthly length-frequency distributions (LFDs) collected from commercial bottom trawls in the northern Adriatic Sea. The results of the analysis confirm the presence of sexual dimorphism in the caramote prawn species, with females exhibiting faster growth rates compared to males. Additionally, the growth performance index supports this observation, further underscoring the importance of accounting for sexual dimorphism in growth modeling and fisheries management strategies. By contributing to a growing body of knowledge on the growth dynamics of the caramote prawn, this study provides valuable insights for sustainable fisheries management in the northern Adriatic Sea. Understanding the age and growth patterns of key crustacean species is essential for developing effective conservation measures and ensuring the long-term health and productivity of marine ecosystems. The findings of this study serve as a foundation for informed decision-making and proactive management practices aimed at preserving the ecological integrity and economic viability of crustacean fisheries in the region.

Length frequency distribution, length-weight relationship and condition factors of Hilsa Shad, Tenualosa ilisha from Bangladesh

Hilsa shad, Tenualosa ilisha, a cherished and economically vital species, thrives in the waters of Bangladesh. It holds a prominent role in bolstering the nation's food security and influencing the ecological dynamics of aquatic ecosystems along the Bangladeshi coast and estuaries. This comprehensive study encompasses data collection efforts on the Hilsa fish species, conducted at 12 commercial landing centers throughout Bangladesh over the course of 2020. The study describes some fundamental components, including length frequency distribution, length-weight relationships, and condition factors, offers invaluable insights into the growth, health, and overall well-being of Hilsa population. Notably, the length-weight relationship analysis revealed size ranges of 11.5-59.2 cm and 11.0-49.0 cm total length for females and males, respectively. The observed b values indicated positive allometric growth (b > 3.00) for female population and negative allometric growth (b < 3.00) for male population in the length-weight relationship. Among the condition factors scrutinized, Fulton's condition factor emerged as the most reliable indicator for assessing the health and condition of the Hilsa population. This study offers valuable insights for biologists, aiding in the assessment of the species' status and providing essential information for fishery biologists and conservation biologists. Such insights are instrumental in the management and ultimate conservation of this iconic species in Bangladesh.

An assessment of demersal fisheries by trawling in less than 50 m of water off Egypt’s Mediterranean coast

Trawl fishing is identified as one of the most significant factors that could affect the diversity of demersal fish groups but not for all depth strata. Since the increased exploitation of Non-Indigenous Species (NIS) has caused the trawl fishing grounds to shift towards shallower seas where their biomass density is maximum, this study aimed to assess demersal fisheries by bottom trawls in the Mediterranean water off Egypt at depths less than 50 m. In this study, data from eight bottom-trawl hauls were used to describe the diversity of the demersal fish catch. The hauls varied in their species composition and both in the number and the weight of individuals. The length frequency distribution of the most occurred species was studied. A total of 87 species were identified in the catch, out of which 32 were recognized as NIS. The percentages of most of the NIS decreased from the east to the west of the surveyed area. There are always changes in fish diversity because of increasing fishing efforts on demersal fish communities, but not for all depth strata, therefore, a monitoring program has to be designed for better assessment of fisheries resources in the Mediterranean water off Egypt.

Length Of Service Of Health Workers With The Ability Of Triage Hospitals In The IGD RSUD DR. H. BOB BAZAR

Triage is the process of making a decision to prioritize the need to provide actions and therapy for patients in the emergency room based on the level of emergency. Data on emergency room visits in South Lampung in 2014 were 29,877 cases. RSUD Dr. H. Bob Bazar, SKM Kalianda is the only one of the highest referral hospitals in South Lampung Regency, based on the data obtained there are still cases of unexpected events (KTD), data on improving the quality and patient safety of KTD rates ranging from 1-2%, where one of them is a misidentification of the patient. This study aims to determine the relationship between the length of service of health workers with the ability of triage hospitals in the Emergency Room of RSUD DR. H. Bob Bazar, SKM Kalianda, South Lampung in 2020.This type of quantitative research is analytic design and cross sectional approach. The population and sample were 21 nurses and midwives with a total sampling technique. The data analysis test used in this study uses the Chi-Square test.The results of the study revealed that the frequency distribution of the characteristics of respondents, aged 31-40 years were 9 respondents (42.86%), men were 13 respondents (61.90%) and DIII education were 10 respondents (47.62%). Frequency distribution of length of tenure of health workers, with the category of new tenure of 11 respondents (52.4%). Frequency distribution of the ability of triage hospitals for health workers, with the category of incapacitated as many as 8 respondents (38.1%). There is a long-term relationship of work with the ability of triage hospitals health workers. The results of the analysis were obtained (p-value 0.024 <α 0.05). OR: 15,750. It is expected that the management of RSUD Dr. H. Bob Bazar, SKM Kalianda in order to be able to carry out direct supervision related to the ability of triage hospitals for health workers, as well as providing training for health workers on duty at IGD who have not received triage hospital training.

Population Study of Kedukang Fish (Hexanematichthys sagor) in The Waters of Percut River, Percut Sei Tuan District, Deli Serdang Regency, North Sumatera

Kedukang fish (Hexanematichthys sagor) is a consumable fish that is widely caught by fishermen and the community. Kedukang fishing is carried out every day in the Percut River, resulting in a decline in its population. This study aims to analyze the population by looking at density, sex ratio, growth pattern, gonad maturity level, gonad maturity index and fecundity of kedukang fish and analyze the relationship between physical-chemical factors of waters with population density of Kedukang fish. Samples were taken using purposive sampling method at 3 observation stations with 2 repetitions. Fish samples were taken using a net fishing gear installed at low tide and lifted at high tide. The results showed that the population density of kedukang fish in Percut River was low ranging from 0.048-0.123 ind/m2. The sex ratio kedukang fish at each observation station has an average of 1:0.5. The growth pattern of fish is allometric negative. The frequency distribution of fish length ranged from 21.5-47.9 cm. The greatest number of fish caught had a length range of 30.3-34.7 cm as many as 9 fish. The level of gonad maturity kedukang fish is dominated by TKG V. The average gonad maturity index of female kedukang fish is highest at the TPI location which is 20.729% and the highest fecundity at station II which is 4622.6. The relationship between the density of the kedukang fish population is very strong and positively correlated with DO, light intensity and nitrate. The population density of kedukang fish was strongly and negatively correlated with pH and phosphate.

Investigation of androgen receptor CAG repeats length in polycystic ovary syndrome diagnosed using the new international evidence-based guideline

BackgroundTo study whether CAG repeat polymorphism of androgen receptor (AR) contributes to the risk of polycystic ovarian morphology (PCOM) with antral follicle count (AFC) ≥ 20 in the context of new international guideline of polycystic ovary syndrome (PCOS).MethodsBlood of 109 PCOS cases and 61 controls were collected for the measurement of AR CAG repeats length by sequencing. The mean number and frequency distribution of CAG repeats length were observed. Detailed analysis was conducted by dividing PCOS cases into low AFC group (L-AFC, AFC < 20) and high AFC group (H-AFC, AFC ≥ 20) according to the new international evidence-based guideline.ResultsThe portion of individuals with lower CAG repeats length in H-AFC group was significantly larger than those with higher CAG repeats length. Logistic model revealed individuals with lower CAG length tended to develop H-AFC.ConclusionLower CAG repeats length in the AR gene of PCOS cases increases risk of PCOM.

Automated mapping of bedrock-fracture traces from UAV-acquired images using U-Net convolutional neural networks

This contribution presents a novel U-Net convolutional neural network (CNN)-based workflow for automated mapping of bedrock fracture traces from 0.55 cm spatial resolution aerial photographs, acquired by unmanned aerial vehicles (UAV), over the Wiborg Rapakivi granite outcrops in the islands off the coast of the Loviisa Region in Southern Finland. The workflow comprised training a U-Net CNN using a small subset of photographs with manually traced fractures for optimizing the network parameters using the root mean squared propagation optimizer and sigmoidal focal loss function for semantic segmentation of input images and pixel-wise identification of fracture traces. The ridge detection algorithm was then applied to the U-Net prediction results, followed by vectorization of the fracture-traces pixels as vector polylines representing the traces of fractures. Both intensity values of the pixels and topological connectivity were used in the process of vectorization. Quantitatively the results were assessed using various accuracy assessment metrics. Qualitative evaluations of the results were implemented by comparisons of orientations and length-frequency distributions of automatically- and manually-mapped traces.The results show that the model has the class-balanced accuracy score 0.945, predicting 88.79% of the fracture-trace pixels. Bedrock outcrops with well-exposed surfaces present high true positive rates (>99%). The demonstration (test) site has the class-balanced accuracy score of 0.873 and 75% true positive rate. Additionally, the fracture trace networks replicate the orientation distributions of the manually digitized traces. The length distributions of automatic traces, however, differ with varying intensity from the manual trace length distributions. However, this study demonstrates that the workflow can be successfully applied to UAV-acquired images for fast and efficient automated mapping of bedrock-fracture traces during the initial phases of structural characterization of a region.

SEX RATIO, SIZE AND WEIGHT STRUCTURE, LENGTH-WEIGHT RELATIONSHIP AND CONDITION FACTOROF THREE DEMERSAL FISH SPECIESOF SENEGALESE WATERS, WEST AFRICA

This study examined size and weight structure, length-weight relationship (LWR) and condition factor (K) for three demersal species caught by small-scale fisheries: Cephalopholistaeniops, Boopsboops and Plectorhinchusmediterraneuson the Senegalese coast from September 2013 to August 2014.Driftnets were the most commonly used fishing gear to catch fishes, followed by longlines n° 7 to 12 and gillnets (35-40 mm mesh).Females outnumbered malesin all seasonsin the landingssites and Length-frequency distributions varied significantly between sexes for all seasons (P&lt;0.05). The value of exponent b of length-weight relationship of combined sexesforB.boops, C.taeniopsand P.mediterraneus, were found to be respectively 2.8332, 3.0938 and 2.8511. Slopes of females and males LWRsdid not differ statistically within the same season, while they differed between the warm and the cold season. Analysed data showed that the condition factor (K) of B. boobswas less than 1, indicating that this species was not in good physiological stateKscore of 0.95±0.13), while for C. taeniopsand P.mediterraneus(K score respectively of 1.46±0.20 and 1.30±0.15) the values weregreater than 1,implied that this demersal fish was in good physiologicalcondition.The data collected provided new information on the morphological and physiological characteristics of these species populations.

SEX RATIO AND BIOMETRIC INDICES OF PAMA CROAKER, OTOLITHOIDES PAMA (HAMILTON, 1822) FROM THE BAY OF BENGAL, SOUTH-WEST BANGLADESH

The Pama croaker, Otolithoides pama is a prominent marine species under Sciaenidae family. This Sciaenid fish is a popular table food and a perceptible protein source for Bangladeshi rural people. Our research highlights a comprehensive description of the biometric indices of O. pama sampled from the Bay of Bengal, south-west Bangladesh, together with sex ratio, length-frequency distribution, growth pattern, form factor, Fulton’s condition and prey-predator status. Overall 252 specimens (male = 171 and female = 81) were sampled by gill net during 2022 on seasonal basis (summer, rainy and winter). Length and weight of the sampled fish were assessed with measuring board and digital balance. While the sex ratio (male: female = 1.00:0.47) deviated from the conventional ratio of 1:1, total length varied from 13.0 to 26.7 cm for pooled data. Both sexes revealed negative allometric growth (b &lt; 3.00) pattern as a whole. Form factor (a3.0) was found 0.0074 which stated that the fish possessed a fusiform body shape. The mean Fulton’s condition factor denoted an indecorous state of health. Alternatively, prey-predator status was found quite suitable for O. pama population. The outcomes of our research would be highly effective for executing sound management policy in the marine water of Bangladesh.

Life History Traits of Gangetic Ailia Ailia coila (Hamilton 1822) in the Tetulia River, Southern Bangladesh

Abstract The near-threatened Ailia coila, commonly referred to as Gangetic ailia, is a catfish species in the Ailiidae family that is indigenous to Bangladesh, Pakistan, Nepal, and India. This study describes the comprehensive explanation of life-history traits of Ailia coila, including length-frequency distribution (LFD), growth pattern (length-weight relationships, LWRs and length-length relationship, LLR), form factor (a 3.0 ), condition factors (allometric, K A ; Fulton’s, K F ; relative, K R and relative weight, W R ), size at first sexual maturity (L m ), optimum catchable length (L opt ) and natural mortality (M w ) from the Tetulia River in southern Bangladesh. Additionally, L α , a 3.0 , L m , M w and L opt from various water bodies worldwide using the existing literature were calculated in this study. A total of 316 samples were randomly collected occasionally using traditional gear for a year from July 2021 to June 2022. With an accuracy of 0.01 cm and 0.01 g, each fish’s total length (TL), standard length (SL), and body weight (BW) were measured. The group from 10.00 to 10.99 cm TL was numerically leading and the b values of LWRs indicate positive allometric growth. The a 3.0 was 0.005 and K F was the best for assessing the well-being of A. coila. Additionally, W R indicates that the habitat was imbalanced with higher predators. The calculated L m , L opt and M w were 9.19 (~ 9.2 cm TL), 10.7 cm TL and 1.37 year−1 for A. coila in the Tetulia River, respectively. These insights are vital for future research and recommending suitable management strategies for A. coila in the Tetulia River and neighboring basins.

Length-weight relationship, condition factor, and length frequency distribution of the common sole Solea solea in Lake Manzalah, Egypt, with the first record for Atherinomorous forskalii

Length-weight relationship, condition factor, and length frequency distribution of the common sole Solea solea in Lake Manzalah, Egypt, with the first record for Atherinomorous forskalii

The biological aspect of shark which landed in Karangsong’s Port, Indramayu, West Java

This study aimed to evaluate the number of catches and describe the biological aspects of sharks landing at Karangsong’s Port Indramayu, West Java. The study was conducted from July until August 2022 with the survey method. Data were taken by purposive sampling method including species, number of catches, sex, maturity level, total length, weight, fishing gear, and location. Data were analyzed to evaluate the catch while biological aspects were used to determine the condition of sharks. Analysis of biological aspects included sex ratio, length frequency, and the level of male sex maturity, as well as the length-weight relationship. A total of 407 sharks consisting of 7 species were dominated by mature sharks. Include Carcharinus dussumieri (33,2%), Carcharinus sorrah (23,8%), Carcharinus limbatus (0,2%), Sphyrna lewini (8,4%), Rhizoprionodon acutus (1,5%), Chiloscyllium punctatum (12,5%), Loxodon macrorhinus (8,4%). The results showed the frequency distribution of fish length and weight is 44 cm to 106 cm and 0,2 to 8,5 kg. Statistical test results showed that sharks had growth patterns negative allometric and Biological aspects showed an unbalanced sex ratio.Keywords: Allometric; Growth; Sex ratio; Shark

Cherax quadricarinatus: Identifying potentially invasive species in Lake Laut Tawar through their bio-population aspects

Cherax quadricarinatus is an introduced species that is deliberately stocked in Lake Laut Tawar, Takengon, Indonesia. This study aims to analyze bio-population aspect of this species, including length frequency distribution, length-weight relationship, condition factors, and biology reproductive. A total of 361 individual was sampled bi-weekly from October to December 2021 in Lake Laut Tawar, Central Aceh, Indonesia. The carapace length of the crayfish ranged from 26.5 to 69.9 mm CL, with the length class mode being 41.69 mm CL. The growth pattern of freshwater crayfish is negative allometric (b<3) as described as an equation W = 0.0002CL29522 (R2 = 0.907). The sex ratio of C. quadricarinatus between male and female was in balance ratio (1:1) (Chi-square test result). The length of maturity (L 50) in male was 49.49 mm CL, while in female was 47.41 mm CL. The highest gonad somatic index (GSI) was in December at 1.02, while the lowest was in November at 0.79. Fecundity of female ranged from 267 to 970 eggs.

Reproduction and growth of the Red Sea goatfish Parupeneus forsskali in its new environment (Cyprus, eastern Mediterranean Sea)

In the Mediterranean Sea, six species of Mullidae have been recorded, four of them being alien to the area. The most recent arrival in the Mediterranean is the Red Sea goatfish (Parupeneus forsskali), which was first spotted there in the year 2000. Although P. forsskali is endemic to the Red Sea and the Gulf of Aden, it has recently expanded its distribution; it was confirmed in Cyprus in 2014. Since then, it has established a thriving population around the island, and is now commercially important. In the present study, the spawning season and gonad development of P. forsskali off the coast of Cyprus were studied, along with important biological parameters. Macroscopic and histological analyses of the gonads indicated five maturity phases for both ovaries and testes. The gonadal maturity phases and the gonadosomatic index indicated that P. forsskali spawns in the summer months, with the peak of the spawning season in July. Males were bigger, heavier, and more abundant than females, and the length-weight relationship was found to be TW=0.0065 TL3.17 for males and TW=0.0086 TL3.07 for females, both indicating positive allometric growth. The size at first sexual maturity (LM) was 14.2 cm for males and 11.8 cm for females. Five age groups were identified from the length-frequency distribution (0-4 years old). Age group 1 was the most dominant one, containing almost 60% of the sampled individuals. Natural mortality (M) declined with age, and the mean natural mortality coefficient across ages was 0.563 year-1. Overall, this is the first study that provides important information on the spawning season of the Red Sea goatfish and other estimations on various biological traits in its non-native habitat that can be of great importance for fisheries management.

Growth, mortality, and resource utilization of Gymnocypris chui in Langcuo Lake of Tibetan Plateau, China.

To investigate the growth, mortality, and resource utilization of Gymnocypris chui in Langcuo Lake of Tibetan Plateau, we measured body length and body weight of 389 fish based on four sampling surveys from October 2018 to November 2019. We identified the ages through lapillus. Based on frequency distribution of body length, we estimated the growth and mortality coefficients of G. chui in Langcuo Lake and the utilization status of existing population resources according to the Beverton-Holt dynamic comprehensive model. The results showed that G. chui were mainly composed of individuals aged 2 to 19 years in Langcuo Lake, with a length-body weight relationship equation of W=0.0105L3.042. The von Bertalanffy growth equation revealed that the fish had an asymptotic body length of L∞=37.28 cm, growth coefficient of k=0.160, and theoretical growth starting age of t0=-0.887 a. The total mortality coefficient Z was estimated as 0.48, based on the length-converted catch curve method. According to Pauly's empirical formula, the natural mortality coefficient M was 0.34, fishing mortality coefficient F was 0.14, and exploitation rate E was 0.29, indicating that G. chui resources in Langcuo Lake were not over-exploited. Considering the growth and mortality of G. chui in Langcuo Lake, fishing is appropriate, with a recommended fishing length of Lc=22.37 cm.

Relationship between fish body and sagittal otolith morphometrics in the pool barb Puntius sophore (Hamilton, 1822) from the Ganga and Punpun rivers of Bihar, India

The present study estimated the morphometric relationships between body and sagittal otolith of the economically and nutritionally important pool barb Puntius sophore (Hamilton, 1822). A total of 266 fish specimens were collected monthly from the Ganga and Punpun rivers of Bihar, India from September 2021 to March 2022 Length-weight relationships (LWRs), length frequency distribution, condition factor and otolith aspect ratio were assessed. The fish length and weight ranged from 5.57 cm to 11.17 cm and 1.18 g to 18.98 g, respectively. The b value in LWRs (b&gt;3) were estimated as 3.20 and 3.17 for Ganga and Punpun, respectively. Condition factors indicated optimal growth conditions for this species in both the rivers. The fish and otolith morphometrics showed a positive correlation, and the highest coefficient of determination (R2) was observed between total fish length and otolith weight (R2= 0.942) followed by fish length and otolith length (R2=0.90). All of these relationships are significant to fisheries management and useful for future time series studies on food-feeding habits, stock structure, environmental change and resource conservation. Keywords : Coefficient of determination, Condition factor, Fish otolith, Growth, Length-weight relationship

Short communication: Length-frequency distribution, length-weight relationship and condition factor of two grey mullets from Lagos Lagoon

There is a growing interest in examining of economically important fish species with excellent mariculture potentials in lagoons of coastal states. Members of the family Mugilidae, which are permanent residents in Lagos Lagoon form a mainstay of fish protein source and are potential candidates for such investigations. Length-frequency distribution, length-weight relationship, condition factor and molecular characteristics of two grey mullets, Mugil cephalus and Liza falcipinniswere investigated in Lagos Lagoon. A total of 52 samples (26 specimens of each species) of the fish were collected from the Lagos Lagoon. The standard length ranged from 10.0 – 19.2 cm and 12.0 – 18.2 cm for M. cephalus and L. falcipinnis respectively, with corresponding weights of 13.90 – 105.00 g and 36.00-129.00 g respectively. The growth pattern of the species showed negative allometric, b = 0.32 and 0.65 respectively. The condition factors were 1.81 and 2.16 respectively and this meant both species were in good condition.

From Staple Food to Scarce Resource: The Population Status of an Endangered Striped Catfish Pangasianodon hypothalamus in the Mekong River, Cambodia

Striped catfish Pangasianodon hypopthalmus (Sauvage, 1878) is a flagship catfish species of the Mekong River region, a commercially valuable food fish that is important in freshwater fisheries, and a popular aquaculture species in many Asian countries. The species was assessed as “Endangered” by the International Union for Conservation of Nature (IUCN) due to range contraction and declining abundance, though the status of the species’ wild population in Cambodia, a critical habitat for the species, is not well understood. Here, we assess the population status of the striped catfish in Cambodia using multiple sources, including time-series catch data and length frequency distribution data from a commercial fishery (stationary trawl bagnet or dai) operated in the Tonle Sap River from 1998/99 to 2017/18 and larval drift data monitored in the Mekong River in Phnom Penh from 2004 to 2018. We found that there was a significant decline (R2 = 0.54, p = 0.0002) in the catch (metric tonnes) of the striped catfish from the commercial dai fishery over the last two decades. Similarly, length-based indicator analysis indicates that striped catfish mean length and abundance have both declined over the study period, raising concerns about the sustainability of river catfish fisheries. Moreover, long-term larval drift monitoring in Mekong River shows that there was a marginally significant decline in the quantity of striped catfish larvae/juvenile drifting downstream to the lower floodplain over the last decade. Changes in flood index (extent and duration of flood) in the Tonle Sap floodplain affected by the Mekong’s flow are likely key factors driving the decline of the wild populations of the striped catfish. Both larval fish abundance and floodplain fish harvests have a significant positive relationship with Mekong flow and flood extent. Indiscriminate fishing exacerbates pressures on striped catfish stocks. Therefore, actions such as maintaining natural seasonal flows (flood timing, extent, and duration) to the Tonle Sap floodplain and protecting migratory fish stocks from overharvest and habitat fragmentation are essential to the persistence of stocks of striped catfish and other large-bodied migratory fishes that utilize both the Cambodian Mekong and Tonle Sap floodplains.

A study of influence zone for railway stations of different hierarchy in the Indian Railways: analyzing passenger travel patterns

ABSTRACT The transportation planning of Indian Railways has become increasingly complex due to the growing population and increasing demand for mobility. To develop an efficient and effective last-mile transportation system, it is important to identify the extent of the influence zone of railway stations. This can guide policy decisions and infrastructure development. This research paper focuses on mapping the influence zones of 40 railway stations across the Northern Railway Division of India. It uses the travel length frequency distribution to analyze the distribution of passengers’ travel distances. The study shows that influence zones for railway stations vary significantly based on their hierarchy level. Higher-hierarchy stations tend to have larger and more dispersed influence zones, while those of lower-hierarchy stations tend to be smaller and more localized. The findings can be used to guide the expansion of existing stations and the improvement of transportation services. Overall, this study provides a valuable contribution to the field of transportation planning for Indian Railways. It demonstrates the importance of influence zone mapping in developing an efficient and effective transportation system.