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Sustainability of Organic Farming: A Review via Three Pillar Approach
Get PDFOrganic farming (OF) whose primary feature is the avoidance of chemical inputs, offers multiple economic, environmental, and social benefits, and is one obvious facet of efforts to make the agri business more sustainable. The concept of sustainable organic farming was first introduced in the mid-90s. Major studies on sustainable organic farming indicate that it encompasses three pillars: a) economic, b) environmental, and c) social. OF has been studied in the existing literature from the perspectives of these pillars, but these perspectives have not yet been sufficiently combined. In response, this paper summarizes the current state of the literature on OF in the context of sustainability pillars, to do so the study conducts a review, based on academic articles, which are thematically selected, analyzed and categorized according to sustainability pillars (economic, environment and social) vis-à-vis OF. These research and literary sources linking OF with sustainability pillars are analyzed and discussed based on current developments. First, this study develops a comprehensive view of organic farming in terms of sustainability. It further elucidates the research findings related to each pillar. This paper also brings out how the function of organic farming contributes to long-term sustainability by enhancing environmental conservation, economic viability, and farmer welfare and product quality. The findings indicate that i) OF is gaining popularity as a research area in relation to sustainability pillars ii) there is a paucity of published research that combines all the three pillars in the context of organic farming and iii) the social aspect of organic farming is very less addressed
Experimental investigations on fibre reinforced geopolymer concrete as repair material for pavements
Get PDFGeopolymer is a relatively new construction material which could be produced by the chemical action between alumino-silicate material such as fly ash and alkaline solutions like sodium silicate or sodium hydroxide. Geopolymer concrete (GPC) reduces the CO2 emission by 9 % compared to the concrete made with ordinary portland cement. Fibre reinforced geopolymer concrete (FRGPC) has already been used as a repair material for different construction purposes such as for tunnel linings and sewage pipes repairs due to its improved tensile characteristics and crack control properties. This study involves the experimental investigations on FRGPC as a repair material for rigid pavements. A mixture of sodium silicate and 8M sodium hydroxide solution is used as the alkaline activator to prepare the fly ash based geopolymer concrete. To increase the mechanical properties at ambient temperature calcium additives in the forms of calcium hydroxide and calcium oxide are added separately by replacing fly ash in the proportion 3%, 5% and 7% by weight of fly ash. Further to increase the low tensile strength of GPC, addition of polypropylene fibre in 0.2%, 0.4% and 0.6% by volume of concrete were also incorporated. The aspect ratio of the polypropylene fibres used is 300. The optimum values were determined based on the fresh concrete properties and mechanical properties. The results showed that the 7 day compressive and tensile strengths of FRGPC were increased by 36% and 14% respectively from fly ash GPC. The bond strength between the pavement substrate and the geopolymer repair material is also studied. The bond strength of the fibre reinforced repair material is found to be more than the permissible values as per relevant codes of practice. Abrasion resistance of the repair material is also tested as a measure of durability aspects to check the suitability for usage on rigid pavements.
Keywords—Geopolymer Concrete, Alumino-Silicate, Rigid pavements, Substrate, Alkaline solution, Repair materia
Experimental investigation on fly ash based self-compacting concrete with metakaolin.
Get PDFSelf-Compacting Concrete (SCC) is a fresh concrete which is highly flowable, and it can flow readily into place, fill the formwork without any compaction and without undergoing any significant segregation. It is used in the construction where it is hard to use vibrators for consolidation of concrete. High amount of cement and chemical admixtures used in SCC reduces its wide scale usage. Metakaolin can be used as a better substitute to cement due to its cementitious properties. Metakaolin combines with Ca(OH)2 produces additional cementation compounds and makes concrete strengthen. This study aims to experimentally investigate the fresh and strength properties of flyash based self-compacting concrete with different percentage replacement levels of metakaolin with cement. To obtain the optimum percentage of metakaolin in flyash based SCC in which metakaolin is partially replacing cement at 10%, 15% and 20% by weight of cement. M40 grade equivalent flyashbased SCC was established based on fresh properties such as flow ability and passing ability and strength parameters like compressive strength, spilt tensile strength and flexural strength. The results showed that fresh properties decreased as the metakaolin content increased. The strength parameters increased about 15.2%, 12.82% and 14.1% for 15% metakaolin
Applicability of hydrogen fuel cells in shipping for a sustainable future
Get PDF From 2020, International Maritime Organisation (IMO) rules have banned ships from using fuels with a sulphur content above 0.5 percent, compared with 3.5 percent before, unless they are equipped to clean up sulphur emissions. This will be enforced by fines levied by the IMO’s member states. One of the attempts being made by the shipping industry to reduce its environmental impact is to use Fuel Cell Technology to deliver power to the vessels. Fuel cells as clean power sources are very attractive for the maritime sector, which is committed to sustainability and reducing greenhouse gas and also atmospheric pollutant emissions from ships. Fuel cells operating on hydrogen fuel are an efficient, environmentally-friendly, zero emission, direct current (DC) power source already applied to heavy duty bus, truck, and train applications, and are now under development for marine applications. The only emissions from a fuel cell are water vapour and some heat [1].Renewable hydrogen, generated from solar, wind, hydroelectric, and geothermal sources is considered an ideal fuel for decarbonising society. It can be used for industrial purposes, power generation, heating, and as a transportation fuel. This paper aims to show how the Hydrogen fuel cell systems are one of the best options for ships to meet the future and present IMO environment requirements, along with the challenges and conveniences of using renewable hydrogen compared to traditional marine fuels including a feasibility study of a Hydrogen fuel cell powered ferry.
Keywords: IMO (International Maritime Organisation), sulphur emission, Fuel cells, sustainability, Greenhouse Gas, Hydrogen
Alcances y limitaciones de la participación infantil en orientaciones técnicas de programas ambulatorios SENAME: un análisis documental
Get PDFAmong children's rights, the one about participation acts as a protective factor for their development and wellbeing, and as a means for achieving other rights. In Chile, research in child participation is scarce, especially in the national child protection system, SENAME by its abbreviation in Spanish . It is crucial to promote and safeguard a meaningful child participation,considering the impact that decisions taken in protection systems might have in their lives. This study strives to comprehend the scope and limitations of child participation in technical orientative documents of SENAME's outpatient programs, through a document analysis using grounded theory. Results show that the concept "participation" in these documents is applied inconsistently, and mechanisms and spaces of participation for children seem diffuse. Children are seen as victims or vulnerable beings in the documents, and that appears to limit their possibilities of participating by themselves; thus, the family or caretakers of the child take a central role in the documents.Entre los derechos del niño, el derecho a la participación es un factor protector para su desarrollo y bienestar, y un medio para la consecución de otros derechos. En Chile, la investigación en participación infantil es escasa, en especial en el sistema de protección infantil, SENAME. Es crucial promover y resguardar una participación infantil significativa, considerando el impacto que pueden tener en sus vidas las decisiones tomadas en los sistemas de protección. Este estudio busca comprender los alcances y limitaciones de la participación infantil en las orientaciones técnicas de los programas ambulatorios de SENAME a través de un análisis documental en base a teoría fundamentada. Los resultados muestran que el concepto de “participación” en los documentos es aplicado de manera inconsistente, y que los mecanismos e instancias de participación para los niños, niñas y adolescentes (NNA) resultan poco definidos. Los NNA son vistos principalmente como víctimas o seres vulnerables, lo cual parece limitar sus posibilidades de participar por sí solos; así, la familia o cuidadores toman un rol central en el proceso
Effect of Extraction Methods on the Characteristics of Agar from Gelidiella acerosa (Forssk.) Feldm harvested from Gulf of Mannar in India
Get PDFAbstract:
Agar is a sulfated polysaccharide extracted from red macroalgae of the species Rhodophyta. These polysaccharides are extensively used in food and pharmaceutical industrial applications. Further application potentials of this hydrocolloid polymer in the packaging industry due to its nontoxic and ecofriendly characteristics open up new opportunities to explore the benefits of these versatile products in uprising arenas. Comparison and systematic impact analysis of different extraction methods and their effects on basic properties of the extracted polysaccharides needs to be studied. Gelidiella acerosa (Forssk.) Feldm samples were collected from Mandapam and Pamban regions in the Gulf of Mannar on the southwestern coast of India. Cleaned, dried and powdered samples were used for polysaccharide extraction. Extraction yield, moisture, optical characteristics, solubility and structural characterization by FTIR-ATR were carried out for agar obtained by different extraction methods AE1, AE2 and AE3 respectively. The variation in the characteristics and properties of polysaccharides obtained by standard methods of extraction identifies AE2 as the best method based on extraction yield and spectral properties. This study paves the way for quality polysaccharides to be extracted for bulk processing considering the final application properties in existing and uprising sectors
Equity divestment and profit rate performance for sustainable development: a study of central public sector enterprises in India
Get PDFDisinvestment can be described as a way of action whereby the Government withdraws its equity capital either in part or in full in public sector enterprises. From 1991-92, the Government of India undertake the process of divesting its equity shares in CPSEs.
The present study has inspected the impact of equity divestment on profit rate performance in terms of ROCE of the CPSEs in India during the period 1998-99 to 2017-18. The study concluded that CPSEs have a proficient negative impact of equity divestment on their overall profit rate performance during the study period. However, the CPSEs have been able to sustain satisfactory average ROCE in the competitive market economy.
Key Words: Equity Divestment, Profit Rate, CPSEs, ROCE
Role of urban forestry in the ecological development of Pune city.
Get PDFThe urbanization enhances the socio- economic and technological growth of the city. The society is benefited in terms of employment opportunities, better lifestyle and healthcare facilities; however, the major drawback of urbanization is overcrowding and environmental degradation of the city. The need and importance of urban forestry is to be analyzed and various measures should be taken to utilize that knowledge in restoring the green cover for achieving the ecological development of a city. The growth pattern seen in the case of Pune city is the expansion of new settlements around the city core, without proper planning and understanding of urban forestry & green spaces. This paper has analyzed various existing issues in the Urban forestry of Pune like Parks & Gardens, Lakes, Hills, streets, etc. and solutions to mitigate those problems are mentioned herewith. The paper has anticipated future challenges and the areas are identified for the proposal of urban forestry in Pune city to improve the urban greenery and create a livable space for the city dwellers
Youths’ perception on cashew production towards poverty reduction.
Get PDFThe study assessed youth perception on cashew production towards reducing poverty in Osun State, Nigeria. The specific objectives are; to describe the socio-economic characteristics of the youths involved in cashew production, identify the factors that encourage the involvement of youths in cashew production and examine the perception of youth about cashew production in Osun State. A multistage sampling procedure was adopted to select 96 respondents and structural interview scheduled was used to collect data from the selected respondents. The data collected were subjected to descriptive analysis such as frequency counts, percentage, mean, standard deviation and inferential analysis such as chi-square analysis to test for the hypothesis. Results show that the majority (83.3%) of the youths that involved in cashew production are male, with mean age of 30.94 ± 2.4 years, an average farm size of 2.19 ± 0.45 hectares and average annual income of ₦164,844 00K ± ₦41,965.40K (116.6). About 53.1 percent of the respondents practice cashew farming mainly to earn a living. Findings from the study show those factors such as unemployment in non-agricultural sectors; favourable environment for cashew production including marketing availability and provide employment opportunity among others are motivational factors that enhances their involvement. Furthermore, source of information (χ2=32.331, p ≤0.01)), sex (χ2=7.513, p ≤0.05), marital status (χ2= 10.603, p ≤0.05) and reason for practicing cashew farming (χ2=29.766, p ≤0.05) had a positive and significant association with perception of youths towards cashew production. The study concluded that youths had a positive perception of cashew production and recommended among others that trainings in cashew value chain activities should be organized by agricultural development stakeholders to promote youth involvement in cashew value chain activities
Innovation and sustainability dynamics in the horticultural sector
Get PDFThe paper focuses on the horticulture sector of India's Kashmir valley, analyzing its sustainable potential within the framework of the agricultural innovation system. The horticulture sector has been very productive in the Kashmir valley by providing economic pathways to most populations, either directly or indirectly. Engaging the science, technology and innovation application in the sector are believed to increase the growth based on production and productivity. However, such applications without limited measure may act detrimental to the environment on economic accounts' interests. Such applications must be productive, economically viable, and environmentally sound; they must conserve natural resources, make optional use of on-farm resources, and enhance the quality of life for farmers, members of rural communities, and society. All such components remark the concept of sustainable development accounting all the three major factors like social, economic and environmental interrelations. In this study, applying the agricultural innovation system framework will help understand the positive and negative aspects of horticulture within sustainable development. This paper argues that the three domains of sustainable development (i.e., social, economic and environmental) in horticulture will not steady parallel until innovations implemented are projected in an appropriate mechanism.