To assess the potential of energy crops to provide a stock material for biofuel production three crops (rapeseed, sunflower and sweet sorghum) were studied in field experiments in Thessaly, Central Greece in 2007 and 2008. The cropping... more
To assess the potential of energy crops to provide a stock material for biofuel production three crops (rapeseed,
sunflower and sweet sorghum) were studied in field experiments in Thessaly, Central Greece in 2007 and 2008. The cropping activities were recorded. Energy analysis was carried out to assess benefits from the crops. Power requirements and energy consumption during field operations were measured directly using instrumented tractors. Literature data was used for the
energy sequestered to the inputs of the system (indirect energy). Energy budgets were produced taking into account as output either the seed or including the stalks for the two oil seed crops. The results showed that in all cases positive energy balances were achieved. Analysis of the inputs showed that energy for fertilizer was the most important for the rain fed rapeseed but irrigation for sunflower and sweet sorghum. Pumping depth of the irrigation water had a high impact on the energy inputs of the irrigated crops. The overall results gave maximum energy efficiency coefficients of 4.62 for rapeseed without the stalks and 10.68 with stalks, of 2.89 for sunflower without the stalks and 6.16 with stalks and 8.92 for sweet sorghum. An analysis of data from the literature was carried out to assess the effect of new technological developments to the energy sequestered to different inputs. Several developments are expected to improve energy efficiency coefficient, such as variable rate application of inputs, as well as properly designed crop rotations and use of cover crops.
sunflower and sweet sorghum) were studied in field experiments in Thessaly, Central Greece in 2007 and 2008. The cropping activities were recorded. Energy analysis was carried out to assess benefits from the crops. Power requirements and energy consumption during field operations were measured directly using instrumented tractors. Literature data was used for the
energy sequestered to the inputs of the system (indirect energy). Energy budgets were produced taking into account as output either the seed or including the stalks for the two oil seed crops. The results showed that in all cases positive energy balances were achieved. Analysis of the inputs showed that energy for fertilizer was the most important for the rain fed rapeseed but irrigation for sunflower and sweet sorghum. Pumping depth of the irrigation water had a high impact on the energy inputs of the irrigated crops. The overall results gave maximum energy efficiency coefficients of 4.62 for rapeseed without the stalks and 10.68 with stalks, of 2.89 for sunflower without the stalks and 6.16 with stalks and 8.92 for sweet sorghum. An analysis of data from the literature was carried out to assess the effect of new technological developments to the energy sequestered to different inputs. Several developments are expected to improve energy efficiency coefficient, such as variable rate application of inputs, as well as properly designed crop rotations and use of cover crops.
Research Interests:
Research Interests:
The limited resources of fossil fuels along with the highly fluctuating prices, call for investigation to find diesel alternatives. Biofuels from vegetable oils, seems the easiest accessible substitutes as they can be used in conventional... more
The limited resources of fossil fuels along with the highly fluctuating prices, call for investigation to find diesel alternatives. Biofuels from vegetable oils, seems the easiest accessible substitutes as they can be used in conventional diesel engines without lot of modifications. There are though two mainstream attitudes on this approach. The one points that it is immoral to divert environmental resources from food production to energy production when the global population increases and the other claims that without mechanization and fuel to power it, food production will finally be decreased. Conservation tillage adoption may contribute in significant fuel savings by eliminating tillage operations. If they would be combined with on farm biofuel production, they would certainly require less land to be devoted for this purpose. In the present work, based on data of a long term tillage experiment, it was calculated the percentage of land that would be required to cultivate with a b...
Research Interests:
Three experimental fields were cultivated with cotton (Gossypium hirsutum L) in Omorfochori Larissa in 2005. The correlation between electrical conductivity, plant density, plant height and yield were determined to draw conclusions and... more
Three experimental fields were cultivated with cotton (Gossypium hirsutum L) in Omorfochori Larissa in 2005. The correlation between electrical conductivity, plant density, plant height and yield were determined to draw conclusions and make farm decisions for the best management of the fields. The results showed significant variability in yield and Electrical Conductivity in the three fields. Electrical conductivity did not give adequate correlation to yield but it can be used to delineate management zones for targeted soil sampling. Plant height and plant density did not affect yield due to the uniformity of the plants.
In a 9 weeks incubation experiment, gin trash (weakly alkaline material), was added to an acid soil and the residue of cottonseed acid delinting process (acid material), was added to a calcareous soil; a parallel control experiment, was... more
In a 9 weeks incubation experiment, gin trash (weakly alkaline material), was added to an acid soil and the residue of cottonseed acid delinting process (acid material), was added to a calcareous soil; a parallel control experiment, was carried out by adding a commercial organic fertiliser, to the same acid soil, used in the previous treatment with gin trash. The application of those materials to the soils, increased the contents in organic matter and the available P and K. The gin trash, and the organic fertiliser, (chemically neutral materials), corrected the soil acidity but the residue of acid delinting the cottonseed (acid material) reduced the soil alkalinity. The experiment didn’t show any significant effect on mineral N content of the soils
Seed cotton samples were collected in a field where yield maps were taken in the last three years. The samples were analysed in a High Volume Instrument (HVI) automatic machine to assess the lint quality. Thematic maps of the lint... more
Seed cotton samples were collected in a field where yield maps were taken in the last three years. The samples were analysed in a High Volume Instrument (HVI) automatic machine to assess the lint quality. Thematic maps of the lint properties are presented. Correlation analysis was performed between yield and lint properties. Although the lint properties are not given in scales that can be directly compared, a general trend shows a negative correlation of the yield and most of the lint properties. Lint quality correlations with soil properties were significant in many cases. Yield correlation to soil properties was significant only with penetration resistance and Mg.
In order to investigate the possibility to use reduced inputs in fuel and machinery, the follwing five methods of primary tillage for sugar beet establishment were tested in an experiment carried out in Thassaly Greece. 1) Conventional... more
In order to investigate the possibility to use reduced inputs in fuel and machinery, the follwing five methods of primary tillage for sugar beet establishment were tested in an experiment carried out in Thassaly Greece. 1) Conventional tillage, 2) reduced tillage with heavy cultivator, 3) reduced with rotary cultivator 4) reduced with disk harrow and 5) No-tillage. The experiment was combined with two rotations, beets after wheat and beets after cotton, in order to investigate any possible effect. The results showed that growing and final yield of the beets followed the intensity of the tillage method. Conventional as the most intensive, gave the best yields followed by the heavy cultivator. Much less, were the yields of rotary cultivator and disk harrow while no-tillage gave the lowest yield. A different behavior were detected between the five methods of tillage at the two rotations in the first crop development stages, witch is probably owed to the increased amount of weeds after ...
In order to use reduced inputs in cotton crop, an experiment studying the impact of five methods of tillage on soil physical aspects, and cotton growth, established in 1996 in Thessaly Greece. The methods included conventional tillage,... more
In order to use reduced inputs in cotton crop, an experiment studying the impact of five methods of tillage on soil physical aspects, and cotton growth, established in 1996 in Thessaly Greece. The methods included conventional tillage, with ploughing at 25 cm, reduced tillage with heavy cultivator at 20 cm, reduced with rotary cultivator at 15 cm, reduced with disc harrow at 8 cm and no-tillage. Soil at reduced tilled plots presented higher bulk density, shear strength and resistance to penetration. Cotton plants grown under reduced methods of tillage presented delayed emergence, reduced growth, less bolls and lower yields. At harvest, conventional tillage gave the best yield with 4 t/ha of seed cotton followed by heavy cultivator with 3.8 t/ha. The methods of rotary cultivator and disk harrow yielded much less, with 3.2 t/ha. Last of all were the plots of no-tillage which gave 2.8 t/ha of seed cotton. Introduction Cotton, is the most important industrial crop in Greece covering abo...
Minimizing tillage operations by adopting a conservation tillage system can provide significant energy and cost savings. A three year reduced tillage experiment was carried out in Central Greece in order to evaluate the benefits. The... more
Minimizing tillage operations by adopting a conservation tillage system can provide significant energy and cost savings. A three year reduced tillage experiment was carried out in Central Greece in order to evaluate the benefits. The methods were: Conventional tillage (CT) using plough, reduced tillage with a heavy cultivator (HC), rotary cultivator (RC), disk harrow (DH) and no-tillage (NT). Emergence was satisfactory for all treatments but growth and yields were better for CT and HC followed by RC and RC and last was NT plots. Weed populations were lower for CT then reduced tillage plots with NT having the worst problem. Soil water content and dry bulk density were a function of the depth of tillage. Energy consumption was higher in (CT) plots. (HC), (RC), (DH) and (NT) required 24,2%, 44,1%, 72% and 53,8% less energy consumption respectively.
This work presents the instrumentation of a tractor to measure the performance during the work of implements. The forces, produced between the tractor and the agricultural implements during fieldwork were measured by six loading cells... more
This work presents the instrumentation of a tractor to measure the performance during the work of implements. The forces, produced between the tractor and the agricultural implements during fieldwork were measured by six loading cells connecting two " Π " shaped frames. Measurement of torque and angular velocity of power take off is achieved by a gauge that installed between power take off axle and the agricultural implement. Measurement of traveling speed was achieved using a radar and fuel consumption was measured using a special flow meter for diesel engines. Revolutions of tractor's wheels were measured using flux gates. Measurement of working depth of implement was achieved by using a secondary wheel build on the implement testing frame and a rotation potentiometer measuring its position. Loading cells, torque meter and potentiometer produced analog signals while PTO revolution measuring sensor, flux gates, radar and flow meter produced pulses. Analog signals were...
Vinasse did not affect significantly the crop compared to chemical fertilisation. Soil salinty and sodicity increased but not at hazardous levels. Recycling vinasse in local crops once every four years, any adverse effect can be eliminated.
Vinasse application in agriculture as a substitute for chemical fertiliser and soil amendment, was studied in field and in laboratory experiments in Greece. Different application rates, times of application, the effect of soil compaction... more
Vinasse application in agriculture as a substitute for chemical fertiliser and soil amendment, was studied in field and in laboratory experiments in Greece. Different application rates, times of application, the effect of soil compaction induced by the spreading tank and the effect on chemical properties of the soil, were studied in a Wheat Durum crop. Vinasse did cause a delay in plant emergence, but the plants recovered later showing no significant differences in the growth rates and characteristics. Compaction caused an increase in penetration resistance and the shear strength of the soil, but the effect on yields was not always significant. Plots with vinasse gave similar or better yields than conventional fertilisation. Vinasse caused an increase in pH and Na content at a dangerous level in the incubation experiments, but in the field this increase was small and not at hazardous level for the soil.
Yield mapping is considered as the basic element of every precision agriculture system. They were developed the last decade in crops like grain. Lately, commercial mapping systems for cotton were developed. Their application can maximize... more
Yield mapping is considered as the basic element of every precision agriculture system. They were developed the last decade in crops like grain. Lately, commercial mapping systems for cotton were developed. Their application can maximize the economic and minimize the environmental adverse effects for Greece. During the harvesting period of 2001, a cotton yield mapping system was evaluated in fields of Karditsa area. The results of the operation in two fields, with area 4.3 and 1.7 ha respectively, are presented in the present paper. This study showed that every field studied had distinctive zones of equal yield. There was also a significant difference in yield between them despite the small field size. Thus, the variable rate application of inputs may provide economic advantages even in small fields, as is the situation in Greece.
A strip tillage implement was designed, constructed and used for cotton establishment. The implement consisted of a combination of shallow spring and deep rigid chisel tines combined with a rotary digger. It was designed to till a soil... more
A strip tillage implement was designed, constructed and used for cotton establishment. The implement consisted of a combination of shallow spring and deep rigid chisel tines combined with a rotary digger. It was designed to till a soil strip of 0.30 m wide and at a depth of 0.25 m at two rows 1 m apart. Cotton was planted over the strips by a conventional planter. A three-year experiment was established to compare the strip tillage with two other methods˙ conventional tillage using plough and tillage with heavy cultivator. Energy requirements for the strip tillage were 10-28% lower compared to the heavy cultivator and 28-42% lower compared to the conventional method. Soil penetration resistance was used to assess soil loosening by the tools. On the crop rows soil resistance was similar for strip tillage and conventional tillage but higher for the heavy cultivator. Between the rows soil was more compacted in strip tillage plots. Cotton yield showed non-significant differences for the...
In the present study, four reduced tillage methods were compared with conventional tillage using plough. The tillage methods were: 1) reduced tillage with a heavy cultivator (HC), 2) reduced tillage with a rotary cultivator (RC), 3)... more
In the present study, four reduced tillage methods were compared with conventional tillage using plough. The tillage methods were: 1) reduced tillage with a heavy cultivator (HC), 2) reduced tillage with a rotary cultivator (RC), 3) reduced tillage with a disk harrow (DH) and 4) no-tillage (NT). No-plough tillage methods are blamed to cause increased weed infestation. Tillage treatments were combined with four rotations including crops of sugar beet, corn and cotton in order to investigate the possibility to reduce the problem. The results however have shown increased weed infestation especially for the NT. It is obvious that the exclusive use of spring crops in the rotations wasn't the best choice. During the experiment the crop growth and yield as well as the soil compaction were measured. Reduced tillage caused reduced growth and yields. Compared to the conventional method, HC had 3,7-6,6% yield reduction, RC 23,6-34,7%, DH 22,7-34,2% and NT 33-50% yield reduction. The soil i...
The results of three years of yield mapping in cotton in Greece are reported. Yield mapping was taken with a FARMSCAN equipment installed on a two row picker. The equipment performed satisfactorily with the proper care. Data of soil... more
The results of three years of yield mapping in cotton in Greece are reported. Yield mapping was taken with a FARMSCAN equipment installed on a two row picker. The equipment performed satisfactorily with the proper care. Data of soil properties using direct measurements (texture, chemical properties, compaction) and soil EC mapping by a VERIS machine were collected as well .Thematic maps were produced using GIS software. Correlations between yield and soil properties were investigated using SPSS software. The analysis showed that great yield variability was evident in all three years giving high spatial and temporal variability. Yield zones can be produced giving basis for field management. Yield was well correlated to VERIS EC mapping as well as to other soil properties like soil compaction.
Reduced tillage operations can provide soil conservation as well as significant energy savings. A seven year experiment was carried out in Central Greece in order to evaluate the energy budget in the sugar beet crop. Tested methods were:... more
Reduced tillage operations can provide soil conservation as well as significant energy savings. A seven year experiment was carried out in Central Greece in order to evaluate the energy budget in the sugar beet crop. Tested methods were: reduced tillage with a heavy cultivator or subsoiler (HC), rotary cultivator (RC), disk harrow (DH) and no-tillage (NT) compared with a conventional tillage method (CT) using plough. Compared with the (CT) method the reduced tillage methods provided energy savings but also resulted on greater yield losses. As a result, energy productivity was reduced. The results for the (HC) method however were comparable with the (CT).
Cotton is the most important arable crop in Greece. It is cultivated in small fields with average size less than 6 ha. A project aiming at evaluating precision farming technology was initiated in 2001 harvesting period. Yield mapping of... more
Cotton is the most important arable crop in Greece. It is cultivated in small fields with average size less than 6 ha. A project aiming at evaluating precision farming technology was initiated in 2001 harvesting period. Yield mapping of cotton fields in Greece were performed during 2001 and 2002 harvesting periods. Soil samples, from 0-0.30 and 0.30 – 0.60 m depths, were taken in a grid of 15X27 m and analyzed for their chemical properties. Additionally soil penetration resistance in 0-0.50 m depth, was measured at the same grid. The results showed a large yield variation in the fields studied. Using data processing techniques over GIS yield zones can be drawn which can be the basis of any variable input application. Correlation between the parameters studied and yield were not significant apart from soil organic matter and P in the 0-0.30 m depth and clay, sand and Mg in the 0.30-0.60 depth for the year 2001 and soil organic matter, Na and P in the 0-0.30 m depth and silt and sand ...
This paper presents the results of the first year of experiments carried out in Thessaly Greece, to study sorghum crop for biomass production under different cropping practices. The main aim is to produce raw material for second... more
This paper presents the results of the first year of experiments carried out in Thessaly Greece, to study sorghum crop for biomass production under different cropping practices. The main aim is to produce raw material for second generation biofuels. Several varieties of sweet and fibre sorgum were tested under two tillage systems (conventional and no-till), under two row spacings and under three N fertilisation levels and two water application rates. The results showed that Sugar Graze gave the highest yield (18 t of dry matter/ha) followed by Amigo, PR489F, Dale and Topsilo. It is interesting that the varieties reacted differently to soil tillage. Sugar Graze and Dale gave higher yield with conventional tillage while Amigo, PR489F and TopSilo performed better with no tillage. Sugar content of the sip was increasing till the end of October but the highest sugars yield was achieved at the mid of October indicating that respiration was higher than photosynthesis after the mid October....
The introduction of energy crops for biofuel production is expected to cause severe soil degradation as all crop material will be removed from the fields leaving the soil bare and susceptible to soil erosion. The adoption of crop... more
The introduction of energy crops for biofuel production is expected to cause severe soil degradation as all crop material will be removed from the fields leaving the soil bare and susceptible to soil erosion. The adoption of crop rotations to keep the soil covered by vegetation all year round along with the application of reduced tillage or no-tillage methods can offer considerable soil protection. Basic criterion for an energy crop is the positive energy balance. Energy budgets for two energy crop rotations (in the first one all the plant material is removed from the field while in the second one the residues are left on the soil) and five tillage methods were estimated. Crop rotations were combined with: 1. Conventional Tillage (CT), 2. Reduced tillage with heavy cultivator (HC), 3. Reduced tillage with rotary cultivator (RC), 4. Strip tillage or disk harrow (ST/DH) and no-tillage (NT). The energy budget proved to be positive when the whole plant material of a crop was used as an ...
In this paper an attempt has been made to determine the optimum replacement time for cotton pickers under the technical and economic conditions in Greece. For this purpose, five relevant methods have been applied to analyze real data... more
In this paper an attempt has been made to determine the optimum replacement time for cotton pickers under the technical and economic conditions in Greece. For this purpose, five relevant methods have been applied to analyze real data taken by 62 cotton pickers working in Central Greece. Three of the methods consider that the optimum replacement time for cotton pickers
Research Interests:
Irrigation contributes a large part of the costs and energy consumption of irrigated crops of the area. Variable rate technology (VR) can lead to inputs saving in agriculture. Precision agriculture (PA) has proved that most fields are not... more
Irrigation contributes a large part of the costs and energy consumption of irrigated crops of the area. Variable rate technology (VR) can lead to inputs saving in agriculture. Precision agriculture (PA) has proved that most fields are not homogeneous and their input requirements differ considerably in different parts of the field. In most fields, even small ones, there is a high variability of soil properties and topography. Conventional agriculture, by applying inputs at the same rate in the entire field, causes over and under – applications. This results either in deficit of inputs or in waste of them. Over-application causes usually problems to the environment. High spatial and temporal variability exists in yields and in other properties like soil texture. Different soil types can store different amounts of water at the beginning of the season and require different water application amounts and practices. In this study, A FAO water application model was applied in fields with di...
The effect of reduced tillage, cover crop and planting direction on soil erosion was investigated in sloping cotton field in Larissa, Central Greece. The treatments were three tillage methods: conventional tillage using a plough, reduced... more
The effect of reduced tillage, cover crop and planting direction on soil erosion was investigated in sloping cotton field in Larissa, Central Greece. The treatments were three tillage methods: conventional tillage using a plough, reduced tillage using a heavy cultivator, and reduced tillage using a disk harrow, with and without cover crop and tillage and planting of cotton to the
Research Interests:
Research Interests:
This chapter discusses sustainability issues in soil engineering and presents the potential of the use of autonomous tractors in agriculture. While farm machinery is becoming bigger for economies of scale, it causes significant problems... more
This chapter discusses sustainability issues in soil engineering and presents the potential of the use of autonomous tractors in agriculture. While farm machinery is becoming bigger for economies of scale, it causes significant problems in soil erosion and soil compaction. The use of smaller intelligent machines could reduce these problems and the specification requirements for these systems are presented.
Research Interests:
ABSTRACT Conservation tillage research indicated that continuous use of no-tillage or shallow tillage causes an increase in soil dry bulk density, in weed infestation and reduced yields. In a four-year experiment in Greece in a clay loam... more
ABSTRACT Conservation tillage research indicated that continuous use of no-tillage or shallow tillage causes an increase in soil dry bulk density, in weed infestation and reduced yields. In a four-year experiment in Greece in a clay loam soil, five tillage methods using plough, heavy cultivator, rotary cultivator, disk harrow and no-tillage for primary tillage were compared. The adverse effects of conservation tillage mentioned were observed. During the experiment all crop residues were incorporated into the soil. In order to study the effect of using deep soil loosening in conservation tillage plots a change in tillage was made such that plots with continuous five yearof a tillage system can be compared to plots with four years of each studied treatment and for the fifth combination of all others. The results of the experiment showed that conservation tillage methods increased weed infestations. Ploughing for a year decreased weed populations. Five years of no tillage caused an increase of soil dry bulk density to 1.60 g/cm3 compared to 1.12 g/cm3 for conventional tillage. Deep soil loosening after four years reduced dry bulk density considerably. Soil organic matter at a depth 0-10 cm increased after five years of no tillage to 2.78 % compared to 1.56% of conventional tillage and around 1.2 % at the beginning of the experiment. At depth 10-20 cm conventional tillage had 1.77% organic matter compared to 1.33% for no tillage. Year 2001 was a very dry one and reduced tillage methods had the best plant emergence with ploughing and no tillage giving the lower emergence rates. But at the end of the period ploughing gave the best yields.
The goal of this project was to Determine the potential of using precision agricultural practices in small fields throughout Greece. This project is an extension of a prior study carried out in a 0.8ha apple orchard in Northern Greece.... more
The goal of this project was to Determine the potential of using precision agricultural practices in small fields throughout Greece. This project is an extension of a prior study carried out in a 0.8ha apple orchard in Northern Greece. Maps were created to view the variability of four different soil characteristics pH, Nitrogen (N), Phosphorus (P), and Potassium (K). The three nutrients are the major soil ammendments that are applied to crops each year. Results have shown that utilizing management zones can benefit farmers by lowering cost, time spent in the field, and by increasing profits. Management zones can also benefit farmers with small fields by utilizing smaller precision farming equipment.
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Yield and soil mapping were carried out in 2007 and 2008 in a 9.1 ha commercial olive tree plantation for olive oil production. The orchard is in the southern Peloponnese, where olives are cultivated extensively for extra virgin olive oil... more
Yield and soil mapping were carried out in 2007 and 2008 in a 9.1 ha commercial olive tree plantation for olive oil production. The orchard is in the southern Peloponnese, where olives are cultivated extensively for extra virgin olive oil production. The field is planted in rows with about 1650 trees in total. Weed control was practiced during the previous 3 years
Research Interests:
Research Interests:
... Nearly half the area of maize (Zea mays L.) and soybean (Glycine max) in the United States is under reduced tillage methods (Uri, 1999). The data on the reduced tillage effect on cotton are rather limited. Govindasany et al. (1995)... more
... Nearly half the area of maize (Zea mays L.) and soybean (Glycine max) in the United States is under reduced tillage methods (Uri, 1999). The data on the reduced tillage effect on cotton are rather limited. Govindasany et al. (1995) and McConnel et al. ... (Uri, 1999). ...
Research Interests:
Research Interests:
Laboratory of Farm Mechanization, School of Agricultural Sciences, Faculty of Crop Production and Rural Environment, University of Thessaly, Fytoko, N. Ionia, 384 46, GREECE, email:markinos@agr.uth.gr, gemtos@agr.uth.gr ... A precision... more
Laboratory of Farm Mechanization, School of Agricultural Sciences, Faculty of Crop Production and Rural Environment, University of Thessaly, Fytoko, N. Ionia, 384 46, GREECE, email:markinos@agr.uth.gr, gemtos@agr.uth.gr ... A precision farming project has been ...