جستجوی مقالات مرتبط با کلیدواژه "life cycle assessment" در نشریات گروه "منابع طبیعی"

In recent years, due to the limitation of water resources, the use of pressured irrigation methods has received much attention. Although the use of pressurized irrigation systems increases the water productivity, these systems have received less attention in terms of energy use and environmental aspects. So, the aim of this study was to evaluate the energy and environmental indicators of almond orchards under surface and pressured irrigation methods in Shahr-e Kord and Saman region of Chaharmahal and Bakhtiari province. The required data, including information about inputs and energy consumed in almond orchards, were collected using questionnaires and face-to-face interviews. No significant difference was observed regarding the performance of almond production in the two mentioned irrigation systems. Examining the results of water consumption in two systems showed that the pressured irrigation system consumes about 82% less water than the surface irrigation system, while the energy consumption in this system was about 12% more than the surface irrigation system. Energy ratio of almond production in surface irrigation systems was computed as 2.40, while the corresponding value in pressured system was 2.07. In other words, surface irrigation had better conditions in terms of energy indicators. The investigation of the environmental indicators of two irrigation systems showed that the use of the pressured irrigation system reduces the environmental damage

The objective of this study was to evaluate the energy efficiency and environmental ramifications of alfalfa and silage barley production in Qazvin province, Iran, under different irrigation systems. The outcomes showed that subsurface irrigation utilized a total input energy of 95667.71 MJ ha-1, whereas surface irrigation had a positive impact on alfalfa production with a total input energy of 902683.07 MJ ha-1. Flood irrigation had the highest input energy of 110973.39 MJ ha-1 and the lowest output energy of 523644.31 MJ ha-1 compared to other irrigation methods for barley. The primary contributors to On-Farm emissions were diesel fuel and chemical fertilizers, but subsurface irrigation systems had lower levels of diesel fuel related pollutants due to reduced usage, while flooding irrigation systems had higher levels of such contaminants. Based on the finding, silage barley cultivation was a better option than alfalfa cultivation in terms of energy consumption and environment. Based on the finding, silage barley cultivation was a better option than alfalfa cultivation in terms of energy consumption and environment.

Nowadays, there has been an increasing interest in the study of life cycle assessment in all industries namely the construction industry in developed countries with the increasing awareness of the environmental effects of buildings and the emergence of powerful tools for their evaluation. Despite various articles have been published in different countries in this field, none of them has focused on the challenges of using life cycle assessment, related studies, and potential solutions to address the challenges. The purpose of this article is to present a systematic report of a comprehensive review of applied studies in the life cycle assessment method in the construction industry to provide a potential solution for future targeted research in this field. The research method of this paper included a brief review of the subject literature to provide an overview of the life cycle assessment method and systematic selection and study of review articles/books to examine the benefits and challenges of life cycle assessment research. By examining the valid research articles from 2000 to 2023 in the collection of ISI articles and Persian scientific research articles, a total of 72 related articles were studied. First, statistical reports on the geographical and thematic distribution according to the variety of factors affecting the life cycle assessment in construction were presented, and then the objectives of the study, fields of action, databases, tools and environmental effects of the published authoritative articles were examined and the strengths and weaknesses of the recent researches were revealed. The findings showed that the use of integrated databases and also the computational principles and coordinated calculator software along with the unification of functional units lad to the alignment of research within the framework of unit standards, as well as the possibility of comparing and expanding the conclusions and as a result, they provide a more comprehensive picture of the environmental effects of construction products and systems for professionals.

This study was conducted with the aim of determining the energy and indicators and environmental effects in the process of fish farming in Ilam province. The suitable climate and the existence of cold-water springs in the mountains of Ilam province have caused the prosperity of fish farming in this province. The required information was obtained through questionnaires and interviews and then the input and output energies and energy indicators energy and environmental indicators were calculated using the life cycle assessment method and using Simapro software. The results showed that the total input energy per one ton of coldwater fish (rainbow trout) was 44618.7MJ. Growth feed trout (GFT) with a share of 38.61 % had the highest energy consumer input in the production of rainbow trout. The amount of energy ratio, energy efficiency, energy intensity, and net energy gain indicators in cold-water fish production was 0.1784, 0.0214 kg/MJ, 44.61 MJ/kg, and -36658.7 MJ/ton, respectively. In coldwater fish farms, the share of direct, indirect, renewable, and nonrenewable energy was 42.16, 57.83, 77.15, and 22.84 %, respectively. After normalization of environmental indicators, it was found that in fish production, marine aquatic ecotoxicity index and then fossil resource depletion, acidification, global warming and eutrophication indices have the highest amount of environmental pollutants. The biggest environmental burdens in fish farms are from the process of producing fry, feed, electricity, oil fuel, copper sulfate.

Life cycle assessment is a well-known and accurate way to compare the environmental effects of various activities, including the management of agricultural systems.

the present study was reviewed during the crop years 2011-2017. for this purpose, environmental impact analysis, iSO 14040 method was studied in four steps and six impact groups per functional unit equivalent to the production of one ton of lettuce, cabbage and bell peppers.

for this purpose, the highest values of environmental index and resource depletion index were related to lettuce and bell pepper products with values of 0.172 and 0.578, respectively. caps with values of 0.001 and 0.424, respectively, had the highest potential for environmental damage. therefore, in order to manage the amount of fertilizers used, the source of nitrogen supply as well as the time of use must be in accordance with the needs of the crop and agricultural soil to reduce nitrogen losses in any way and also adjust the equipment used to apply fertilizers.

it is ensured that the fertilizer is properly and well placed in the soil and replacing part of it with organic and non-chemical resources in agricultural ecosystems in order to reduce environmental pollution in dezful is necessary and inevitable.

In this research, modeling of energy consumption and environmental emissions for different process of tea production in Gilan province (Iran) were investigated using regression and artificial neural networks. Data related to agricultural and industrial activities of tea production chain were collected through questionnaire survey from tea farms of different counties in Guilan province. Also, the datatbank of agricultural organization, tea research institute and tea factories were collected. The results showed that the total energy input and output for green tea leaf production were 34343.51 and 10996.45 MJ/ha, respectively. Also, the total energy input for dry tea was obtained 64885.23 MJ/ton. The results of the life cycle assessment in tea farms revealed that the highest effect belonged to nitrogen in abiotic depletion, dcidification, eutrophication and global warming potential impacts. The survey of life cycle assessment in the tea processing factories illustrated that diesel fuel had the highest share in abiotic depletion, ozone layer depletion, human toxicity, fresh water aquatic ecotoxicity and photochemical oxidation impact categories. In acidification, eutrophication, global warming potential impacts, green leaf input had the highest share. Moreover, the highest share of marine aquatic ecotoxicity and terrestrial ecotoxicity was belonged to coated paper. The results of energy and environmental emissions modeling for green tea leaf production showed that artificial neural networks can predict the outputs and inputs with more accuracy than regression technique.