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1.
Environ Sci Pollut Res Int ; 30(1): 1854-1870, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35922594

RESUMO

Environmental crises and resource depletion have adversely affected the food security around the world. Food security in the future can be guaranteed by sustainable agriculture that respects the environment. So, it is necessary to decrease the energy consumption of resources for agricultural productions to achieve the maximum sustainability. For agricultural productions, environmental and energy issues are completely interrelated, and a comprehensive evaluation is necessary to manage them in all productions. In this study, energy, environmental, and economic indicators in cantaloupe production were studied. The studied energy indices included energy efficiency, energy productivity, net energy gain, and energy intensity. Life cycle method based on ISO 14040 standard was used to evaluate the environmental impacts. This method includes goal statement, identification of inputs and outputs, and a system for assessing and interpreting the environmental impacts of various agricultural productions. Also, for economic analysis, the average prices of inputs and outputs and also net return (NR), gross return (GR), and profit-to-cost ratio were used. The results showed that nitrogen fertilizer (32.28%) and diesel fuel (30.52%) had the highest and cantaloupe seeds (0.39%), and oil consumption in tractor engines (0.43%) had the lowest share of energy consumption, respectively. Energy efficiency, energy productivity, energy intensity, and net energy gain were estimated 0.56, 0.70 kg MJ-1, 1.41 MJ kg-1, and - 11,775.86 MJ ha-1, respectively. The results of the present status of environmental impacts showed that the most effective factor in climate change is direct emissions from the diesel fuel. Also, indirect emissions from phosphorus and urea fertilizers had the highest effect on ecosystem quality. Various machine operations such as primary and secondary plowing, spraying, and transportation were the main causes of high diesel fuel consumption. Economic analysis showed that the profit-to-cost ratio and the productivity values were calculated about 1.6 and 7.27, respectively, which means that for every dollar spent in cantaloupe farms, it produced 7.27 kg of cantaloupe production. The variable costs were estimated at 1154.5 and fixed cost was 1487 $ha-1. Among the variable costs, transportation and fuel costs were the highest with 64.3%. Decreasing the diesel fuel consumption by using appropriate farm management methods and using the reduce tillage methods can play an effective role in reducing the consumption of this input and improving the energy, environmental, and economic indicators in cantaloupe production.


Assuntos
Cucumis melo , Ecossistema , Animais , Gasolina , Agricultura/métodos , Estágios do Ciclo de Vida , Fertilizantes
2.
Sci Total Environ ; 828: 154232, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35283131

RESUMO

Excessive consumption and improper management of inputs would lead to environmental damages, as well as decreased economic benefits. Thus, a thorough examination of the entire production process from the viewpoint of energy flow, economic profit, and environmental effects can identify hotspots and facilitate input management. Accordingly, in the current investigation, energy, economic and environmental aspects of greenhouse cucumber production systems were measured by life cycle assessment (LCA) technique and cumulative exergy demand (CExD) analysis by considering different greenhouse structures. Furthermore, the data envelopment analysis (DEA) approach was used to determine the efficiency of manufacturing units and optimal consumption pattern. The information required was acquired through interviews and questionnaires with 35 greenhouse owners, and consultation with greenhouse enterprises in the Khuzestan province of Iran. Based on the findings, energy consumed was 6626.45 MJton-1 in Sc1, and 6410.32 MJton-1 in Sc 3. The findings of benchmarking revealed that boosting the efficiency of the crop production process can lower input energy by 14.80%. The energy consumption for the construction of the first and second type of greenhouses was calculated to be 14,811.13 and 17,541.73 MJ (1000 m2)-1, respectively. With regard to the production variable costs, chemical fertilizers and labor had the largest contributions to the total expenses, at 7.6 (15.41%) and 7.87 $tonne-1(15.94%), respectively. In the evaluation of the energy and economic indicators, the combined indicator of Energy Intensiveness for the first and second types of greenhouse systems was found to be 80.26 and 77.07 MJ$-1, respectively, indicating higher energy-economic productivity of the first type of system. Based on LCA results, direct emissions due to input consumption (air: carbon dioxide (CO2), and nitrogen oxides (NOx); soil: mercury (Hg), copper (Cu), and lead (Pb)), and indirect emissions induced by chemical fertilizers, greenhouse structures, and chemical pesticides production are the environmental hotspots.


Assuntos
Cucumis sativus , Fertilizantes , Agricultura/métodos , Fertilizantes/análise , Polietileno , Polímeros
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