Quantity and Quality of Dill Essential Oil as Influenced by Organic Fertilizers

Increasing attention is being paid to use of organic fertilizers such as manure and vermicompost which can increased yield and protect the environment. Replacing chemical fertilizers with manures has the benefit of low production cost and imparts beneficial effects on soil. Then an experiment was conducted during 2013 to measure effects of organic fertilizers on essential oil of dill (Anethum graveolens L.). Use of organic fertilizers beneficially affected seed yield, percent of essential oil, and essential oil yield. Essential oil percent was highest due to treatment with compost tea applied to the soil compared to foliar application. The combination of 20 t∙ha-1 of manure and 7 t∙ha-1of vermicompost, without compost tea,producedthe maximum essential oil yield (23.85 kg∙ha-1). The GC-MS analysis of dill essential oil indicated 94% of essential oil compounds were made up of: carvone, α-phellandrene, p-cymene, dillapiole and trans-dihydrocarvone. The maximum value of carvone (73.58%) was obtained by application of 20 t∙ha-1 of manure and 15 t∙ha-1of vermicompost and compost tea in form of soil application

Evaluation of greenhouse gases emission based on energy consumption in wheat Agroecosystems

In order to have sustainable development, it is necessary to manage energy use and greenhouse gases (GHG) emission in all production processes. The aim of this study was to compare wheat production in dryland and irrigated agroecosystems in terms of greenhouse gases (GHG) emission based on energy consumption under different climatic regions. Data were collected from growers using a face-to-face questionnaire during 2013. The results showed that total energy consumption in irrigated and dryland wheat agroecosystems was 53082.9 and 15603.3 MJ ha−1, respectively. Energy use efficiency was 22.1% higher in dryland wheat agroecosystem than irrigated wheat agroecosystem. Total GHG emission for irrigated wheat agroecosystem was 3184.4 kg CO2-eq  ha−1 and 680.36 kg CO2-eq  t−1 while it was 553.1 kg CO2-eq  ha−1 and 381.3 kg CO2-eq  t−1 in dryland wheat agroecosystem. In irrigated wheat agroecosystem the highest GHG emission was 3561.8 kg CO2-eq  ha−1for arid–warm region and the lowest was 2832.6 kg CO2-eq  ha−1 for wet–moderate region. In dryland wheat agroecosystem the highest GHG emission was 584.2 kg CO2-eq  ha−1 for wet–cold region and the lowest was 523.01 kg CO2-eq  ha−1 for semiarid–warm region. In irrigated wheat agroecosystem diesel fuel had the highest emission (46.9%), followed by electricity (36.2%) and farmyard manure (7.5%). In dryland wheat agroecosystem the highest share of GHG emissions belonged to diesel fuels (75.8%), machinery (14.2%) and chemical fertilizers (8.5%), respectively

Investigation the effect of outlet air flow and chamber temperature on some bio-char properties of wheat straw in a fixed-bed oxidative pyrolysis

Soil plays an important role in the sustainability of ecosystems. In recent years, the increasing growth in the degradation of soil resources has drawn attention to management strategies for maintaining the soil quality. Researchers have recently studied the impact of using biochar on physical and chemical properties of soil. It has been found that adding biochar improves the soil quality. Some factors such as pyrolysis chamber conditions, pyrolysis peak temperature and air flow rate affect the physical and chemical properties of biochar including the density, pH, ash content, and so on. In this study, the effect of changes in the air flow rate and chamber temperature in the fixed-bed oxidative pyrolysis on the biochar yield, ash content, density and pH were investigated. For this purpose, a fixed-bed biochar production apparatus with varying chamber temperature and flow rate of outlet air was designed and manufactured. The experiments were performed at four air flow rates of 20, 25, 30 and 35 L min-1 and four temperatures of 350, 400, 450 and 500 °C for wheat straw. The results showed that increasing the temperature and flow rate of the outlet air from the chamber increased the ash content and pH. However, increasing these parameters decreased the biochar bulk density and yield