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A modeling system was used to calculate the resource footprints (land, water, nutrients, energy, fuel, electricity, and carbon) on a large scale in agricultural production systems (Iran as a case study), and this report is an introduction of this modeling system for future studies. Under irrigated conditions, the highest land footprint was observed in pulses and oil grains (0.6 ha t−1). The lowest water footprints were found in silage corn (300 m3 t−1), and the highest water footprints were observed in oil grains (4525 m3 t−1). The highest footprints of nitrogen were observed in maize (31.7 kg t−1), wheat (30.9 kg t−1), and oil grains (30.4 kg t−1), and the lowest value belonged to production of sugar crops (2.6 kg t−1). Most of the energy, fuel, electricity, and greenhouse gas (GHG) emissions were occurred under irrigated cropping systems compared with the rainfed systems. Under irrigated conditions, the highest footprints of energy, fuel, and electricity and GHG emissions occurred in the production of oil grains, and their values were 24397 MJ t−1, 161 L t−1, 1195 kWh t−1, and 1699 kg CO2eq. t−1, respectively. In general, wheat production in Iran has the highest cost in terms of resource use (water, elements, energy, and carbon) compared with the other plant products. Livestock and poultry products (especially red meat) also had the highest ecological footprint among the products. [ABSTRACT FROM AUTHOR]

The current noticeable climate change that has a significant impact on the environment and agricultural systems has become a serious concern for human society. Followed by the industrial activities of the global community and increased concentrations of greenhouse gases in the atmosphere, these changes are still considered as a threat to food safety and the environment. Changes in minimum and maximum temperature, rainfall amounts, and precipitation pattern, changes in CO2 concentrations, and complex interactions between these factors and different crops are studied in the form of different probabilistic scenarios to get a glimpse of the future cultivation situation. Agriculture in Qazvin Plain is based on the water transferred from Taleqan Dam and groundwater. Since today these resources are facing issues like restriction on transfer and draw off, which is because of growth of interest in city dwelling, inappropriate water consumption patterns and over-exploitation, agriculture is sensitive to probable changes in water requirements and it is necessary to predict these changes for better management in the future. This study was carried out to investigate the effect of climate change on growth indices for three crops including wheat, barley, and maize in Qazvin Plain with different possible climate change scenarios, in the form of five large-scale climate models and three greenhouse gas emissions scenarios in 30 years' time from 2021 to 2050 as well as from 2051 to 2080. Results showed that biomass production, grain yield, and water use efficiency in three crops of wheat, barley, and maize have increased up to 20–40% in future periods in Qazvin region climate. Growing degree-days (GDD) of these three crops have increased by 20%. Transpiration has risen by 10% in wheat and maize; however, it was stable on average in the first period and slightly decreased in the second period in barley. The transpiration coefficient has reduced by 5% for wheat and barley and has increased by 15% for maize. Results are valid as long as the initial growing conditions of these three plants are done as before, and the irrigation scheduling is performed according to the present period in spite of climate change. [ABSTRACT FROM AUTHOR]

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Abstract: Climate is the most important factor determining the sustainability of agricultural production systems. A qualitative land evaluation was carried out for the Mashhad plain, Khorasan Razavi province, Iran, to assess the suitability of the land to grow the locally most important crops, i.e. wheat (Triticum aestivum), sugar beet (Beta vulgaris) and corn (Zea mays) using a Geographical Information System (GIS). The possible growing seasons were defined as early (10 September–20 June) and late (10 October–20 July) season for wheat, early (15 March–15 October) and late (15 April–15 November) season for sugar beet, and early (1 May–1 November) and late (15 May–15 November) season for corn. The study area covered approximately 99.915ha−1. Climate variables were taken into account including maximum, optimum and minimum daily average temperatures and were obtained from 30years agro-meteorological data set from 12 synoptic stations. Growing Degree Days (GDDs) were determined for wheat, sugar beet, and corn crops from sowing to harvest. To produce digital elevation model for Mashhad plain two sources were used on utilization of the IRS III satellite images with resolution that is 23.5m, and topographic maps with scale of 1:25000. Aspect and slope layers were produced by Arc GIS 9.2 software. The study identified suitable elevation, slope, and GDDs for optimal growth and indicated that high yields are possible for wheat, sugar beet, and corn on the Mashhad plain. The study also identified the most suitable regions of the Mashhad plain for each crop. [Copyright &y& Elsevier]

Abstract: Groundwater irrigation consumes considerable energy as well as water resources across the globe. Using a case study from Iran, this paper explores how enhanced farm water management can help in reducing groundwater exploitation and subsequently limiting energy consumption and the carbon footprint of the groundwater economy. Groundwater use for irrigated agriculture in Iran has increased vastly over the last three decades. We estimate that groundwater pumping consumes 20.5billionkWh electricity and 2 billion liters of diesel and contributes to 3.6% of the total carbon emission of the country. Thus there is an opportunity to reduce energy use and carbon emissions by pumping less water. However, groundwater use remains important for food security. To identify opportunities for water conservation within agricultural fields, the SWAP model was applied to simulate crop growth and field water balance for three major irrigated crops, i.e. wheat, maize, and sugar beet in the Gamasiab River Basin, one of the highest groundwater using irrigated areas of Iran. The model simulations showed that by adopting improved irrigation schedules and improving farm application efficiencies, water productivity will increase, and irrigation water withdrawals from groundwater can be reduced significantly with no reduction in yields. While these improvements may or may not result in water saving and retarding the ground water decline, depending on the fate of excess application, they will have significant water quality, energy, and carbon implications. Such reduction in irrigation application can result in 40% decline in energy consumption and subsequently carbon emission of groundwater use. [Copyright &y& Elsevier]

Abstract: Seed placement and failure to establish a uniform plant stand are critical problems associated with conservation tillage production of corn (Zea mays) following wheat (Triticum aestivum) in Iran. Our objectives were to evaluate the performance of a conventional corn planter (with runner type openers) equipped with row cleaners and to demonstrate for local farmers an affordable method for reduced tillage corn production. The reduced tillage system studied consisted of disking followed by chisel plowing and another disking ahead of planting. A ground-driven row cleaner was fabricated and mounted to each unit of a common pneumatic single seed planter and used to plant at three forward speeds (4, 7, and 10kmh−1) into no- (NR), half- (HR), and whole- (WR) residue plots. This compares to a typical system of complete removal or burning the previous wheat residue in the region. The amount of residue retained in the row, depth of seed placement, emergence rate and three indices of uniformity in seed spacing were determined. Row cleaners performed best at the highest forward speed, retaining an average residue cover of 920kgha−1 compared to 1350kgha−1 for plots planted without using row cleaners. This 430kgha−1 more residue removal was a significant improvement with regard to soil–seed contact. For the HR and WR plots, residue removal averaged 45% and 70% of that present before planting, suggesting that the row cleaners will work more effectively at high residue conditions. Without row cleaners, initial residue levels resulted in a shallow planting depth, but when row cleaners were used, planting depth was maintained near the target depth (5cm). The desired planting depth was also obtained at 7kmh−1 in the HR plots. Row cleaners significantly increased plant emergence rate with the maximum (3.5plantsd−1 m−1) being observed for seeds planted at 4kmh−1 in the HR plots. This agrees with others who showed high residue reduces plant emergence and grain yield. Planting with row cleaners into HR plots at 7kmh−1 resulted in the lowest miss and precision indices comparable to those of a no-residue plot (16.5% and 17.5%, respectively), and a quality of feed index as high as 69% was obtained at similar conditions. Our results indicate that equipping available planters with row cleaners can result in a successful reduced tillage corn production system and thus satisfy both farmers and authorities promoting conservation tillage. In addition to the environmental benefits of the proposed system, it is expected that the savings in time, fuel and labor would offset the cost of row cleaners. [Copyright &y& Elsevier]

It is very important to determine the irrigation water requirement (IR) of crops for optimal irrigation scheduling under the changing climate. This study aimed to investigate the impact of climate change on the future IR and yield of three strategic crops (winter wheat, barley, fodder maize) in the semi-arid Qazvin Plateau, Iran, for the periods 2016–2040, 2041–2065, and 2066–2090. The Canadian Earth System Model (CanESM2), applying IPCC scenarios rcp2.6, rcp4.5, and rcp8.5, was used to project the monthly maximum and minimum temperatures and monthly precipitation of the region. The results indicated that the maximum and minimum temperatures will increase by 1.7 °C and 1.2 °C, respectively, under scenario rcp8.5 in the period 2066–2090. The precipitation will decrease (1%–13%) under all scenarios in all months of the future periods, except in August, September, and October. The IR of winter wheat and barley will increase by 38%–79% under scenarios rcp2.6 and rcp8.5 in the future periods. The increase in the IR of fodder maize will be very slight (0.7%–4.1%). The yield of winter wheat and barley will decrease by ~50%–100% under scenarios rcp2.6 and rcp8.5 in the future periods. The reduction in the yield of maize will be ~4%. Serious attention has to be paid to the water resources management of the region. The use of drought-tolerant cultivars in the region can be a good strategy to deal with the predicted future climatic conditions. [ABSTRACT FROM AUTHOR]

• Water conservation is the best way to increase water management efficiency in agriculture and reduce potential negative environmental impacts. • Residue improves soil tilth and adds organic matter to the soil as it decomposes. • Crop residue can reduce the rate of water evaporation and runoff, increase penetration of water and therefore improve soil water conservation. Wheat (Triticum aestivum L.) residues and water management are major problems in southern part of Iran where irrigated wheat-corn (Zea mays L.)-wheat rotation is a common practice. A 2-year (2015–2016) field experiment was conducted as a split plot design with four replications to determine the influence of different irrigation regimes (50, 70, and 100% of water requirement) and wheat residue rates (0, 25, and 50%) incorporation into the soil on sweet corn (Zea mays L V. Saccharata) growth, grain yield, and some soil properties at School of Agriculture, Shiraz University, Shiraz, Iran. The results showed that the highest plant height (187.12 cm) and leaf area index (3.49) were obtained when the crop was normally irrigated (100% of water requirement) and sown into the 25% incorporated wheat residues. Furthermore, canned yield (68%) and water use efficiency (WUE) increased with normal irrigation and 25% residue incorporation compared to the 50% wheat residue rate. The highest grain protein (14.67%) was achieved under incorporation of either 25 or 50% wheat residue into the soil, while the highest grain sugar (2643.5 mg g−1) was obtained when the crop was moderately irrigated (70% of water requirement) with 25% residue incorporation into the soil. The highest soil nitrogen (N) and soil organic carbon (SOC) were achieved with normal irrigation and 50% residue incorporation in both years.In general, adopting an adequate rate of wheat residue (between 25%–50%) accompanied by decreasing irrigation volume to 70% water requirement of corn is recommended in semi-arid agroecosystems. [ABSTRACT FROM AUTHOR]