v.10 n.6 December

Carbon Stock Assessment in Peat Soil and Mangrove Regrowth Phase of Shrimp Ponds: A Case Study of Ecosystem Restoration in the Indian Sundarbans

Rangika Bandara, Prosenjit Pramanick, Ricardo Gobato, and Abhijit Mitra

Parana J. Sci. Educ., v.10, n.6, (1-7),  December 1, 2024.

DOI: 10.5281/zenodo.14030715

Abstract

This study investigates Peat Soil Organic Carbon (PSOC) dynamics in abandoned shrimp ponds across two stations in the Indian Sundarbans, Chemaguri (21°39'49.32"N; 88°09'11.88"E) and Sagar Island (South) (21°39'04.68"N; 88°01'47.28"E) selected based on the abundance of shrimp ponds. Shrimp farming, which expanded in the lower Gangetic delta region during the early 1990s, led to extensive loss of mangrove cover and significant reduction in soil carbon storage. In 1994, we recorded the Soil Organic Carbon (SOC) levels of 0.93% and 0.84% in the peat soil during the drying period of shrimp farms (October) at Chemaguri and Sagar Island (South) respectively. Following the introduction of an afforestation program in 2000 aimed at restoring the mangrove ecosystem, significant changes in SOC were observed. By 2014, SOC levels rose to 1.85% and 1.79%, with further increases to 2.45% and 2.01% by 2024, at the respective stations. The study utilized the Walkley-Black method to estimate the SOC levels in the peat soil at different stages like the drying phase of shrimp culture period (1994) and restoration phase (2014 and 2024). This research underscores the positive impact of afforestation programs on mangrove soil recovery and the sequestration of peat soil carbon, confirming the role of mangrove restoration in climate change mitigation and ecosystem rehabilitation

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What do children think is inside a crab on a seashore in Paraná - Southern Brazil? (Case Study)

Amauri Betini Bartoszeck, and Sue Dale Tunnicliffe

Parana J. Sci. Educ., v.10, n.6, (8-12),  December 1, 2024.

DOI: 10.5281/zenodo.14225293

Abstract

Children from Southern Brazil have a basic knowledge of internal anatomy of the crab from their everyday life? A total of 434 children 194 aged 5, 67 aged 10 and 173 aged 12 were asked to draw what they think is inside a Brazilian crab which lives in a mangrove swamp. A real preserved seashore crab was presented in the classroom during the class period and children were given 15 minutes to draw the drawing on a A4 sheet of blank paper. These pupils attended 3 public and 1 private schools in an urban area 100 km away from the seashore in Curitiba town. Analysis of the collected drawings by 5 years old pupils revealed that most achieved level 2 “one or more internal organs at random”, those at 10 years old achieved level 4 “two or more internal organs in appropriate position, whereas those children 12 years old achieved level 5 mentioning a few organ systems according to the grade level rubric developed by the authors. On the whole very few drawings depicted organ systems. This study intended to evaluate the mental model represented by the drawing which in this case is the expressed model what children think is inside the crab. Invertebrates are a very neglected area in the curriculum of the preschool and first grades of primary school. Internal anatomy investigation of what children think is inside invertebrates is very scarce. This study has shown that children have a poor understanding of the internal organization of organs and organ systems of crabs sometimes pupils depicting human or vertebrate organs (e. g. lung instead of gills, “dog” bones) as a template for explaining their understanding. Heart and brain were the most mentioned organ both genders by all participating ages and respiratory and digestive systems the most mentioned by twelve years old pupils. Educational implications are discussed.

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Уравновешенный шарнирно-рычажный механизм

Balanced hinged–lever mechanism

Владимир Николаевич Суханов

Vladimir Nikolaevich Sukhanov

Parana J. Sci. Educ., v.10, n.6, (13-21),  December 1, 2024.

DOI: 10.5281/zenodo.14225925

Abstract

The article presents the principle when two forces applied from one side of the lever mechanism, for their mutual balancing, have one direction of their action. To implement this principle, it is necessary to bring the action of forces to their common support with the possibility of their movement in different directions relative to each other. The paper considers the case when two unidirectional forces compensate each other, since they have oppositely directed degrees of freedom. On this basis, a mechanism is proposed that belongs to flat hinged (lever) mechanisms, and which can be used in the design of industrial and lifting cranes. This principle will allow us to take a fresh look at dialectics, which will require presenting the struggle of two opposites as the summation of two one–sidedness (united actions) with diametrically opposed possibilities (rights freedoms, interests, ...).

Аннотация

В статье представлен принцип, когда две силы, приложенные с одной стороны рычажного механизма, для их взаимного уравновешивания имеют одно направление своего действия. Для реализации этого принципа необходимо привести действие сил к их общей опоре с возможностью их перемещения в разных направлениях относительно друг друга. В статье рассмотрен случай, когда две однонаправленные силы компенсируют друг друга, так как имеют противоположно направленные степени свободы. На этой основе предложен механизм, относящийся к плоским шарнирным (рычажным) механизмам, и который может быть использован при проектировании промышленных и подъемных кранов. Этот принцип позволит по–новому взглянуть на диалектику, что потребует представить борьбу двух противоположностей как сумму двух односторонностей (объединенных действий) с диаметрально противоположными возможностями (правами, свободами, интересами, ...).

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Rényi wavelet extropy of scaling signals

Julio César Ramírez Pacheco, Homero Toral Cruz, and David Ernesto Troncoso Romero

Parana J. Sci. Educ., v.10, n.6, (22-25),  December 1, 2024.

DOI: 10.5281/zenodo.14232536

Abstract

Recently, wavelet based informations tools are being used for fractals to unveil their complexities and provide more elaborate analyses. In this article, the time-domain definition of Rényi extropy is extended to the wavelet domain and a closed-form expression of this extropy for scaling signals of parameter (alfa) is obtained. Based on the theoretical results, wavelet Rényi q-extropy planes are obtained for various q and a range of the fractality parameter and, based on these, a complete characterization of the complexities of fractal signals based on Rényi extropies are obtained. Moreover, potential applications for fractal signal analysis are highlighted and useful relations amongst different wavelet R´enyi extropy planes are provided.

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