Irrigation
S. Habibi; M. Khoshravesh; R. Nouri Khajebelagh
Abstract
IntroductionIn today's world, challenges related to agriculture, food security, water and energy resources, productivity, and greenhouse gas emissions have emerged as significant issues for global societies. Through their international impacts, these challenges have led to economic, social, and environmental ...
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IntroductionIn today's world, challenges related to agriculture, food security, water and energy resources, productivity, and greenhouse gas emissions have emerged as significant issues for global societies. Through their international impacts, these challenges have led to economic, social, and environmental changes on a global scale. One of the most crucial issues that should be highlighted is the shortage of water resources. Water, as a vital factor in agriculture and food production, holds special importance. Therefore, in order to achieve sustainable agriculture, it is necessary to pay attention to the energy indicators, the efficiency of water consumption in the production of agricultural products and the amount of greenhouse gas emissions. In general, a combination of energy indicators, water efficiency and reduction of greenhouse gas emissions in agriculture can help to develop sustainable agriculture and preserve the environment and help to provide safe and accessible food for the society. The aim of the present study was to investigate the indicators of physical water, energy efficiency, and greenhouse gas emissions on alfalfa and barley crops in two different climates: a warm and arid climate (Shahr-e-Qom Plain, Qom) and a temperate and humid climate (Sari Plain, Mazandaran). This was done to assess the impact of climate on the outcomes of these indicators. Materials and MethodsTo investigate the physical water efficiency and evaluate energy indicators in this study, major agricultural products in Sari and Sharifabad Plains, including barley and alfalfa, were analyzed using cross-sectional data from the agricultural year 2021-2022. Initially, the sample size was determined based on the Cochran formula and the Bartlett method (2001). Subsequently, sampling was carried out using a questionnaire designed by the researchers themselves. The questionnaires totaled 250 (Sari Plain: 150, Sharifabad Plain: 100), and the collected information included the amount of input consumption and production quantity. The questionnaire, designed by the researcher, was validated for validity and reliability by experts and specialists. The inputs used in the study of water efficiency and energy indicators for the mentioned products in Sari and Sharifabad Plains included person-days of human labor, machine working hours, fuel consumption of machines, the quantity of nitrogen, phosphorus, potassium fertilizers per hectare, the quantity of various chemical pesticides (herbicides, fungicides, and insecticides) per liter per hectare, the amount of water consumption in cubic meters per hectare, and the amount of seed consumption in kilograms per hectare.Results and DiscussionThe results of the descriptive statistics of input consumption in Sari and Sharifabad Plains in barley and alfalfa crops showed that the highest input consumption of manpower in the cultivation of alfalfa crops in Sharifabad Plains with an average of 225 hours per hectare, the highest amount of fertilizer consumption related to the alfalfa crop in Sharifabad Plain is related to nitrogen fertilizer with an average of 130 kg per hectare, the highest amount of fuel consumption of machinery related to alfalfa crop in Sari Plain with an average of 405 liters per hectare, the highest amount of water consumption related to alfalfa crop in Sharifabad Plains with an average of 17500 cubic meters per hectare and the highest yield of alfalfa was obtained in Sharifabad Plains with an average of 11550 kg per hectare. The obtained results indicated that the highest input energy level in Sharifabad Plain for alfalfa was 5,674.50 MJ per hectare. The results of energy efficiency indicated that alfalfa production in Shahrifabad Plain had the highest value with 0.19 kilograms per MJ, while this index for alfalfa in Sari Plain was 0.13 kilograms per MJ. Additionally, the energy efficiency for barley in Shahrifabad Plain was 0.13 kilograms per MJ, and for Sari Plain, it was 0.12 kilograms per MJ, showing a somewhat similar level. The physical water use efficiency results revealed that the highest and lowest efficiency levels were observed for barley in Sari Plain, amounting to 0.96 kilograms per cubic meter, and for alfalfa in Shahrifabad Plain, amounting to 0.57 kilograms per cubic meter, respectively. Furthermore, this index for alfalfa in Sari Plain was 0.67 kilograms per cubic meter, and for barley in Shahrifabad Plain, was 0.8 kilograms per cubic meter. The results for greenhouse gas emissions demonstrated that the level of emissions in Sari Plain was higher than Sharifabad Plain, attributed to excessive fertilizer and pesticide use in Sari Plain. The highest greenhouse gas emissions in Sari Plain for alfalfa were 2681.65 kilograms of CO2 per hectare, while in Sharifabad Plain, was 2351.85 kilograms of CO2 per hectare. ConclusionThe overall results indicated that crop performance in humid regions was not higher than in dry and semi-arid regions, and this index depends on various parameters, including water consumption and managerial considerations. However, water consumption in temperate and humid regions is significantly lower than in dry and semi-arid areas due to higher precipitation. This result is increased efficiency in temperate and humid regions.
Mohsen Soleimanzadeh; Hossein Khademi; mozhgan sepehri
Abstract
Introduction: Iron is one of the essential micronutrients for plant growth. The total amount of iron in soil is often more than plant iron requirement, but the low solubility of iron compounds in many of soils leads to low uptake of this element by plant and eventually, results in iron deficiency symptoms ...
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Introduction: Iron is one of the essential micronutrients for plant growth. The total amount of iron in soil is often more than plant iron requirement, but the low solubility of iron compounds in many of soils leads to low uptake of this element by plant and eventually, results in iron deficiency symptoms in plant. Iron is the structural component of cytochromes, leghemoglobines and ferredoxins. This element participates in many vital activities of plants, such as photosynthesis, respiration and fixation of molecular nitrogen. Some of micaceous minerals including muscovite and phlogopite which contain significant amounts of iron are plentiful in soils of arid and semiarid regions of Iran. The purpose of this study was to evaluate the ability of two plant species (alfalfa and barley) to uptake structural iron from muscovite and phlogopite.
Materials and Methods: The greenhouse experiment was conducted as factorial arrangement based on completely randomized design with three replicates. Treatments consisted of two plant species (alfalfa and barley), two types of micaceous minerals (phlogopite and muscovite) and two nutrient solutions (complete and iron-free).The experiment was done in 700 g pots containing a mixture of quartz sand (as the filling material), cocopeat and micaceous minerals (phlogopite and muscovite). Quartz sand and micaceous mineral were obtained from a mine near Hamadan City in Iran. For this purpose, X-ray elemental analysis fluorescence (XRF) was used to investigate the possibility of using quartz sand and micaceous mineral. Micaceous minerals were passed through a 140 mesh sieve and then, samples were saturated with Ca using a 0.5 M CaCl2 solution. To remove the excess Cl, saturated minerals were washed with distilled water several times and then samples were oven dried at 105 °C. Pots were filled with a mixture of 600 g quartz sand, micaceous mineral and cocopeat. The amount of mineral was added until there was 0.35% K2O in all pots. Two barley and alfalfa seeds were planted in each pot. During the growth period (150days), plants were irrigated and fed with distilled water and nutrient solutions, respectively. At the end of the growth period, shoots and roots of plants were harvested andiron contents of plants extracts were measured by atomic absorption.
Results and Discussion: For two plant species, the results showed that iron concentration in the pots containing phlogopite and fed with iron-free nutrient solution was in a sufficient range for both barley and alfalfa. The amount of iron uptake by alfalfa in both substrates and nutrition solutions was more than barely. It seems that alfalfa is able to uptake more amount of iron due to the abundant root exudates. The highest amount of iron uptake by root is related to alfalfa cultivated in substrates containing phlogopite and fed with iron-free nutrient solution. The highest barley shoots weight is related to substrates containing phlogopite and muscovite fed with complete (with iron) nutrient solution, whereas in alfalfa, the highest shoot weight is related to phlogopite-containing substrates fed with iron-free nutrient solution. Plants cultivated in two substrates containing phlogopite and muscovite did not show deficiency symptoms until late growth period and appearance of plants fed with iron-free nutrient solution was completely similar to those fed with complete nutrient solution. The amount of iron uptake by roots is several times higher than that of shoots. High uptake of iron by plant roots are affected by phytosiderophores produced by plant roots. Phytosiderophores produce chelate Fe (III) in the rhizosphere. These chelates are absorbed into the apoplast of roots and Fe (III) is separated from them as a result of certain reactions, and takes the path to xylem.
Conclusion: The results of this study indicate that iron structural phlogopite and muscovite minerals can provide iron requirement for plant during the growth season. Since phlogopiteis a tri-octahedral mineral, it has more Fe (II) and its structure is weaker than muscovite, and hence, is able to provide more iron for the plant during growth season. But muscovite is di-octahedral and its structure contains Al+3, so octahedral may not easily release its elements into the rhizosphere for the plants utilization. The factors influence the release of elements from micaceous minerals are structure and type of mineral. Alfalfa is able to release more iron from micaceous minerals thanks to its root systems and ability to produce more shoot. Since micaceous minerals have considerable amount of iron and are able to provide iron requirement for plant during growth season, it is recommended to investigate whether micaceous minerals are able to supply this element for longer growth periods.
R. Mosavi; E. Sepehr; A. Samadi; Mirhasan Rasouli-Sadaghiani; B. Sadeghzade
Abstract
Introduction: Phosphorus (P) is regarded as the most important soil nutrient after nitrogen (N) for plant growth and development as it plays key roles in plant metabolism, structure and energy transformation. Also, although soil P is often abundant in both organic and inorganic forms, it is frequently ...
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Introduction: Phosphorus (P) is regarded as the most important soil nutrient after nitrogen (N) for plant growth and development as it plays key roles in plant metabolism, structure and energy transformation. Also, although soil P is often abundant in both organic and inorganic forms, it is frequently a major or even the prime limiting factor for plant growth. Low phosphorus (P) availability is a major global global constraint to crop production. In most soils, soil and fertilizer P are easily bound by either soil organic matter or chemicals, and thus are unavailable to plants unless hydrolyzed to release inorganic phosphate. Phosphorus efficient plants play a major role in increasing crop yields due to shortage of inorganic P fertilizer resources, limited land and water resources, and increasing environmental concerns. Therefore, the development of P-efficient crop varieties that can grow and yield better with low P supply is a key for improving crop production. Enhancing P efficiency in plants can be achieved through enhancing P acquisition, utilization, or both.
Materials and Methods: In order to investigate the effect of microbial inoculation on phosphorus efficiency of different genotypes of barley, a glasshouse factorial experiment was conducted in a completely randomized block design with 10 barley genotypes and different phosphorus (P) treatments including control (P0), phosphate rock (RP), RP inoculated with phosphate solubilizing fungi (RP+F), RP inoculated with phosphate solubilizing bacteria (RP+B), RP inoculated with both fungi and bacteria inoculums (RP+B+F), and soluble phosphate (PS) in three replications. After sieving (2 mm sieve), and, air - drying of soil samples, basal nutrients mixed thoroughly at the following soil test results. Then, soils placed in plastic pots (3 kg). The P treatments as (KH2PO4 and Rock Phosphate) 80 mg kg-1 soil added at the depth of 5-cm of soil. After 9 weeks the plants were harvested, grain dry weight (GDW) and grain P concentration measured and then content P (TP), P efficiency (PE), P acquisition efficiency (PACE) and P utilization efficiency (PUTE) were calculated.
Results and Discussion: The results indicated that microbial inoculation had significant effect (P
J. Givi
Abstract
In addition to qualitative and quantitative land suitability evaluation, economical evaluation can be carried out as well, based on net or gross benefit per surface area unit. The present research was done to evaluate land suitability, qualitatively and economically,, by different methods for irrigated ...
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In addition to qualitative and quantitative land suitability evaluation, economical evaluation can be carried out as well, based on net or gross benefit per surface area unit. The present research was done to evaluate land suitability, qualitatively and economically,, by different methods for irrigated maize, wheat, potato and barley in Shahrekord area. In this regards, qualitative land suitability class was determined by matching land characteristics with the studied crops growth requirements, using simple limitation method and ALES program. Economical land suitability evaluation was carried out, using "internal rate of return", "gross profit", "net present value" and "benefit/cost ratio" methods which are included in the ALES program. The results showed that qualitative suitability class in all of the studied land units for irrigated maize, wheat and barley is S2 and for irrigated potato in 73% of the units is S2 and in 27% of them is S3. As the "net present value" method is used, % 73 and % 27 of the land units are classified as S2 and S1, respectively for all of the studied crops. For wheat and maize, all of the land units are classified as S1, as gross profit, benefit/cost ratio and internal rate of return methods are used. For potato and barley, using gross profit and internal rate of return methods, % 73 and % 27 of the land units are classified as S2 and S1, respectively and as the benefit/cost ratio method is used, economical land suitability class in all of the land units is S1.
