Tillage and Irrigation Impacts on the Efficiency of Fossil Fuel Utilization for Hungarian Vetch Production and Fuel-Related CO 2 Emissions

Abstract

Improving energy efficiency in tillage is critical for developing sustainable agriculture and mitigating fuel-related CO₂ emissions. However, data on energy efficiency and CO₂ emissions across various tillage-sowing practices remain scarce in terms of vetch production. The study aimed at evaluating the impact of four tillage-sowing practices (conventional tillage [CT], Reduced-I and II, and no-tillage [NT]) on the fuel consumption, energy productivity, and fuel-related CO₂ releases in Hungarian vetch production. The study was performed in Turkey, in semiarid conditions using two water applications (rainfed and irrigated) under two different crop rotations (rainfed: vetch-wheat-fallow and irrigated: vetch-wheat-sunflower). The study findings revealed that while CT had the highest diesel-fuel consumptions (52.2 L/ha in irrigated and 53.1 L/ha in rainfed), the lowest values were determined in NT (16.4 L/ha in irrigated and 16.6 L/ha in rainfed). Total energy requirements were the highest in CT, and determined 11827.4 MJ/ha (5229.1 MJ/ha direct and 10502.5 MJ/ha nonrenewable) in irrigated rotation and 9328.5 MJ/ha (3013.6 MJ/ha direct and 8004.6 MJ/ha nonrenewable) in rainfed conditions. Moreover, CT provided the lowest energy ratio (4.41 in irrigated and 3.87 in rainfed). NT practice required significantly lower total (20.6% in irrigated and 27.8% in rainfed), direct (52.5% in irrigated and 68.8% in rainfed), and nonrenewable energies (23.1% in irrigated and 32.3% in rainfed) and provided higher energy ratio (24.0% in irrigated and 53.2% in rainfed) compared to CT. Irrigation increased energy gain by 48.2% on average. Conservation tillage logarithmically reduced CO₂ emissions in both rotations. NT and reduced tillage practices generated 68.7% and 42.2% lower emissions on average compared to CT (151.1 kg CO₂/ha), respectively. It was concluded that NT can be a suitable practice to achieve higher energy efficiency and lower CO₂ emissions in vetch production. However, reduced tillage can be favorable due to the limited application of NT in most countries.

Introduction

Proper economic and environmental approaches to meet food security goals in the agriculture sector are vital in formulating global environmental policies. Therefore, energy consumption and energy-related greenhouse gas (GHG) emissions from agricultural practices are an important concern for policymakers (Li et al., 2016).

Emissions through agricultural treatments comprise a considerable portion of total GHG emissions (Jaiswal and Agrawal, 2019). The share of the agricultural sector of total GHG emissions is 22% (Platis et al., 2019). The use of fossil fuel in agricultural power machineries and irrigation pumps contributes to carbon emissions (Houshyar, 2017). CO₂ is also emitted at high levels from the degradation of agricultural and other lands by human-induced activities directly [Environmental Protection Agency (EPA), 2019]. The amount of global GHG emissions reported in 2017 was 50.9 Gt, which is about 55% higher than in 1990 and 40% higher than in 2000 (Oliver and Peters, 2018). Anthropogenic emissions accounted for probably 55% of total global emissions in 2016 (Xi-Liu and Qing-Xian, 2018).

The adequacy of measures that could be considered to reduce GHG emissions by way of soil management is still uncertain (Abdalla et al., 2016). Global impact of management practices such as tillage and crop rotation on cropland soils needs further evaluation under different soil and climatic conditions (Sainju, 2016). Tillage is both an energy intensive practice and affects soil organic carbon stocks and GHG emissions due to organic matter decomposition (Abdalla et al., 2016). High-level consumption of fossil-based energy during the tillage process emits high amounts of CO₂ into the atmosphere from the burning fuel. Lu and Lu (2017) confirmed that diesel fuel use was the major consumer of energy and producer of GHG emissions in various tillage practices.

Conservation tillage practices encompass zero tillage or no-till, reduced or minimum tillage, mulch tillage, ridge tillage, and contour tillage practices, and the most common ones are zero tillage (no-till) and reduced or minimum tillage (Busari et al., 2015). Conservation tillage and no-tillage (NT) practices have various advantages such as low carbon emission, save time and fuel, require less labor, and higher agricultural productivity (Karayel and Šarauskis, 2019).

Reducing tillage processes mitigates GHG emissions both through decreased use of fossil fuels in field preparation and increases soil organic matter content and sequestration of carbon (Mangalassery et al., 2014). In a study that analyzed the numerous researches conducted in different soil and environmental conditions worldwide to evaluate tillage impact on soil CO₂ emissions, it is shown that NT practice is an effective mitigation measure of CO₂ emissions from dry land soils. It is also concluded that tillage practices result in 21% greater CO₂ emissions than NT practice (Abdalla et al., 2016).

Conventional tillage (CT) requires high amounts of diesel fuel due when increasing the working depth from 0.25 to 0.30 m (López-Vázquez et al., 2019). Lekavičienė et al. (2019) also confirmed significantly increased diesel fuel consumption and tractor's CO₂ emission with increasing penetration depth. Similarly, Sayed et al. (2019) determined minimum amounts of fuel consumption and considerably lower CO₂ emission in NT and minimum tillage practices compared to CT.

Previous study results showed that sustainable crop production with less GHG emissions can be obtained through efficient energy use (Houshyar, 2017). Energy efficiency can be improved with reduced energy input and/or increased output energy. Therefore, more acceptable energy efficiency can be realized with either increased or decreased energy inputs or outputs depending on the input-output energy relationship under different tillage practices. Barut et al. (2011), Kumar et al. (2013), and Hamzei and Seyyedi (2016) have previously reported that higher energy use efficiency was achieved under minimized or NT conditions compared to CT practice.

Huynh et al. (2019) reported that soil productivity and thus crop yield are strongly influenced with changes in the cropping system, soil tillage, and irrigation. Therefore, a suitable cropping system can provide additional contributions to increase productivity and profitability of crops and to provide agronomic sustainability. Decreasing cereal monoculture by adding legumes in rotation systems has long been proven to have productivity and environmental benefits in many parts of the world (Dalias, 2012). Inserting legumes into crop rotations helps reduce the use of fertilizers and energy (Stagnari et al., 2017). Wheat-fallow crop rotation is applied mostly in dry regions with low annual precipitation (<450 mm) (Kumlay et al., 2007). This study was conducted in the Eastern Anatolia Region in Turkey. Approximately 26.2% and 21% of the country's small and large ruminant animals, respectively, are raised in this region [Eastern Anatolia Project (DAP), 2014].

Vetch has also been added as a crop to the wheat-fallow rotation in this region with a low amount of annual precipitation (≈425 mm) to grow animal feed (Olgun et al., 2007). Vetch uses the soil water economically. Dalias (2012) expressed that vetch creates better water economy because it does not consume soil moisture at the same extent as cereal crops and leaves residual soil moisture for the following crop in the rotation.

Nowadays, tillage is being increasingly abandoned as the use of direct sowing machines becomes more widespread and weed control is carried out with herbicides (Abdalla et al., 2016). Conservation tillage practices are being increasingly advocated worldwide for sustainable agriculture due to minimum fuel consumption based on shallow tillage or NT and decreased tillage equipment usage and time, and less CO₂ releases from minimized fuel consumption. However, empirical knowledge regarding energy consumption and CO₂ emissions of tillage-sowing practices in vetch production in both rainfed and irrigated rotations in regions with semiarid climates is limited. Therefore, by studying rainfed and irrigated crop rotations that continued for 9 years, we endeavored to (1) investigate how much CO₂ was emitted from fuel consumption with conventional and conservation tillage-sowing practices during Hungarian vetch production for 3 years and (2) evaluate the effects of different tillage-sowing practices on vetch energy use by many energy evaluation parameters (e.g., the energy ratio, intensity and gain, and the requirements of direct, indirect, renewable, and nonrenewable energies).

Materials and Methods

Experiment area

The field studies were conducted at the Soil-Water Resources Research Station of East Anatolia Agricultural Research Institute in Pasinler District in Erzurum province, Turkey (39.989° N, 41.575° E, 1,720 m a.s.l). The soil type in the study region is Inseptisol according to the USDA soil classification system (Özgül, 2003). The texture class of the surface soil layer at 0–30 cm in the experimental field was sandy clay loam (47.9% sand, 25.5% silt, and 26.6% clay). Electrical conductivity, pH, CaCO₃, and organic matter contents in the surface soil layer before the experiment were also determined as 1.495 dS/m, 7.17, 0.35%, and 1.73%, respectively.

The annual total precipitation and mean temperature in the experimental region were 423.5 mm and 6.1°C in long-term period averages (2000–2016), respectively [Eastern Anatolia Agricultural Research Institute (DATAE), 2016]. Monthly precipitation and air temperature values during vetch growing periods are shown in Fig. 1. First year precipitation values in vetch growing periods were less than the long-year average precipitation values, while other 2-year values were close. In the region with a semiarid climate, summers are short, warm-cool, and dry, while winters are long, cold, and snowy. Therefore, the climate type is described as Dsb (D: continental climate, s: dry summer, and b: warm summer) according to the Koppen-Griger classification (Öztürk et al., 2017b).

FIG. 1.

Monthly precipitation and air temperature values during vetch growing periods.

Experimental design and agricultural operations

The experimental design was a randomized complete block design with three replications. Hungarian vetch production was carried out in 1999, 2002, and 2005 in two crop rotations (rainfed and irrigated), each was planned for a period of 9 years (1999–2008). While vetch-winter wheat-fallow cycle was applied in the rainfed crop rotation, vetch-winter wheat-sunflower cycle was considered in the irrigated crop rotation. Each experimental plot was 15 × 40 m in size and a total of 12 plots for each crop rotation were arranged in the experimental field. The plots under both crop rotations have been treated with four different tillage-sowing practices as CT, reduced tillage-I (RT1), reduced tillage-II (RT2), and NT. The equipment and their technical properties used in different tillage-sowing practices during the vetch production periods are given in Table 1. The effective working depths and widths of all the equipment used were determined with three repeated measurements for each plot in the study. Agricultural equipment was towed with a tractor of 50 kW with a weight of 3,396 kg and economic life of 12,000 h.

Table 1.

Equipments Used in Different Tillage-Sowing Practices in Vetch Production Processes and Their Technical Properties

Tillage-sowing practice	Agricultural process
	Tillage					Sowing		Spraying	Harvesting
	MP	DH	C	CH	RH	DS	NS	P	FM
CT (irrigated)	√	√	—	√	—	√	—	—	√
CT (rainfed)	√	—	√	√	—	√	—	—	√
RT1	—	—	√	√	—	√	—	√	√
RT2	—	—	—	—	√	√	—	√	√
NT	—	—	—	—	—	—	√	√	√
Technical properties
Effective width, cm	88.2	191	194	207.8	185.9	300	250	750	130
Effective depth, cm	25.9	10.9	15.4	6.8	12.2	5.8	6.0	—	—
Weight, kg	440	420	430	440	510	372	1,400	260	398
Economic life, h	2,000	2,000	2,000	2,000	1,500	1,500	1,200	1,500	2,000

C, cultivator; CH, combined harrows; CT, conventional tillage; DH, disc harrow; DS, disc seeder; FM, fingerbar mower; MP, moldboard plough; NS, no-till seeder; NT, no-tillage; P, pulverizator; RH, rotary power harrow; RT1, reduced tillage-I; RT2, reduced tillage-II.

The Hungarian vetch (Vicia pannonica Crantz.) population line seeds were sown at a rate of 130 kg/ha on September 8, 1999, October 2, 2002, and October 13, 2005. Harvests were made on July 11, 2000 and 2003, and June 29, 2006. The 500 g samples taken from green forages harvested in trial plots were air dried in outdoor conditions, subsequently oven dried at 78°C for 24 h, and weighed. Dry forage yield as kg/ha was calculated with dry weight percentage (Taş, 2010). Average vetch dry forage yields for 3 years under irrigated rotation conditions were realized as 5801.57, 6069.08, 6078.81, and 5710.95 kg/ha in the CT, RT1, RT2, and NT practices, respectively. These values under rainfed rotation conditions were determined as 4010.44, 3906.13, 3938.21, and 4435.15 kg/ha with the same order. The plots were fertilized with diammonium phosphate (46–48% P₂O₅ and 16–18% N) and urea (46% N) fertilizers with consideration to the dosage calculated according to the soil analysis results before planting during all vetch production years (Table 2). No chemicals were used to combat weeds in the CT practice due to deep plowing with a moldboard plough, while herbicide at the rate of 0.4 kg/ha using a pulverizator was applied in the other tillage-sowing practices.

Table 2.

The Fertilizer Quantities (kg/ha) Applied to Different Tillage-Sowing Practices Under Two Crop Rotations in Vetch Production Years

Crop rotation	Tillage-sowing practices	Diammonium phosphate						Urea
		1999		2002		2005		1999	2002	2005
		P₂O₅	N	P₂O₅	N	P₂O₅	N	N	N	N
Irrigated	CT	63.45	22.95	58.75	21.25	18.80	6.80	50.60	32.20	50.60
	RT1	63.45	22.95	42.30	15.30	18.80	6.80	50.60	34.50	59.80
	RT2	63.45	22.95	42.30	15.30	37.60	13.60	50.60	34.50	59.80
	NT	63.45	22.95	49.35	17.85	28.20	10.20	50.60	43.70	59.80
Rainfed	CT	42.30	15.30	49.35	17.85	61.10	22.10	41.40	32.20	41.40
	RT1	42.30	15.30	23.50	8.50	28.20	10.20	41.40	36.80	41.40
	RT2	42.30	15.30	49.35	17.85	61.10	22.10	41.40	32.20	41.40
	NT	42.30	15.30	32.90	11.90	37.60	13.60	41.40	36.80	41.40

The quantity of irrigation water applied in different tillage-sowing practices as a 3-year average (mean ± standard error of mean) in vetch production under irrigated crop rotation conditions was 1088.7 ± 8.9, 1045.8 ± 32.6, 863.1 ± 32.8, and 744 ± 14.4 m³/ha for CT, RT1, RT2, and NT practices, respectively. Irrigation quantities were determined considering soil moisture contents measured gravimetrically. Irrigation was done by surface (ponding) irrigation method using groundwater (pH: 7.45, electrical conductivity: 0.225 dS/m and sodium adsorption ratio: 0.64) that was provided by an electrical motor-submersible pump system.

Determination of operational values, input and output energies, energy efficiency, and CO₂ emission

Task times of agricultural equipments used throughout vetch production periods were determined with a chronometer with 1/100 Cmin precision. The effective field capacity (EFC) values of tractors and agricultural equipment needed for determination of the machine energy requirements were calculated with the ratio of the treated area and the actual task time (Hanna, 2016). Real fuel consumptions were measured at a precision of 0.01 mL with specially designed electronic fuel units located between the fuel tank and pistons, as well as the pump and fuel tank. The data were transferred into a storage unit, and evaluated by using a software (ZET) developed by Özden (1995). The human labor requirements were also determined for each agricultural process under operational conditions. Table 3 shows diesel fuel consumption, the EFC, and human labor values of all used agricultural equipment as 3-year averages.

Table 3.

The Operational Values as 3-Year Average of Equipments Used in Vetch Production Processes Under Irrigated and Rainfed Crop Rotation Conditions

Parameter	Agricultural process
	Tillage					Sowing		Spraying	Harvesting
	MP	DH	C	CH	RH	DS	NS	P	FM
Irrigated crop rotation
Diesel fuel, L/ha
CT	25.48	9.24	—	6.53	—	5.50	—	—	5.41
RT1	—	—	11.23	6.61	—	5.74	—	1.18	5.41
RT2	—	—	—	—	18.56	5.60	—	1.18	5.41
NT	—	—	—	—	—	—	9.79	1.18	5.41
EFC, ha/h
CT	0.231	0.824	—	0.991	—	0.993	—	—	0.913
RT1	—	—	0.583	1.010	—	1.030	—	3.197	0.913
RT2	—	—	—	—	0.405	1.038	—	3.197	0.913
NT	—	—	—	—	—	—	0.605	3.197	0.913
Human labor, h/ha
CT	4.943	1.324	—	1.181	—	2.190	—	—	1.212
RT1	—	—	1.949	1.124	—	2.098	—	0.731	1.212
RT2	—	—	—	—	2.758	2.120	—	0.731	1.212
NT	—	—	—	—	—	—	3.574	0.731	1.212
Rainfed crop rotation
Diesel fuel, L/ha
CT	23.87	—	11.16	6.92	—	5.74	—	—	5.41
RT1	—	—	10.43	6.59	—	5.94	—	1.18	5.41
RT2	—	—	—	—	18.90	5.74	—	1.18	5.41
NT	—	—	—	—	—	—	10.01	1.18	5.41
EFC, ha/h
CT	0.243	—	0.670	0.974	—	1.124	—	—	0.913
RT1	—	—	0.620	1.014	—	1.158	—	3.197	0.913
RT2	—	—	—	—	0.418	1.148	—	3.197	0.913
NT	—	—	—	—	—	—	0.644	3.197	0.913
Human labor, h/ha
CT	4.453	—	1.635	1.194	—	1.932	—	—	1.212
RT1	—	—	1.753	1.129	—	1.853	—	0.726	1.212
RT2	—	—	—	—	2.688	1.867	—	0.726	1.212
NT	—	—	—	—	—	—	3.385	0.726	1.212

EFC, effective field capacity.

The total input energy requirement in different tillage-sowing practices was calculated as the sum of the requirements of machinery, diesel fuel oil, human labor, fertilizers, seed, irrigation, and chemical energy. The machinery energy need for the manufacturing of tractors and agricultural equipment was calculated using the equation below (Barut et al., 2011; Karaağaç et al., 2014). $M a c h i n e r y E n e r g y (M J h a^{- 1}) = \frac{W \times E}{T \times E F C}$

where W is the weight of a tractor or agricultural equipment (kg), E is the energy equivalent of the manufacturing of the tractor or agricultural equipments (MJ/kg), T is the economic life (h), and EFC is the effective field capacity (ha/h). Energy amounts spent for other inputs (diesel fuel oil, human labor, fertilizers, seed, irrigation, and chemical) were calculated by multiplying the input amounts with the energy equivalents given in Table 4. Hungarian vetch total forage yield was multiplied by the value of energy equivalent in Table 3 to determine the output energy amount.

Table 4.

Energy Equivalents (MJ/Unit) of Inputs and Output in Vetch Production

Energy parameters	Unit	Energy equivalent	References
Inputs
Diesel fuel oil	L	56.31	Kizilaslan (2009)
Human labor	h	2.30	Gözübüyük et al. (2012)
Tractor	kg	158.5	Gözübüyük et al. (2012)
Agricultural equipments	kg	121.3	Gözübüyük et al. (2012)
Irrigation	m³	2.07	Calculated
Fertilizer (P₂O₅)	kg	12.44	Banaeian and Zangeneh (2011)
Fertilizer (N)	kg	66.14	Banaeian and Zangeneh (2011)
Seed	kg	10.0	Moreno et al. (2011)
Chemical (Herbicide)	kg	238	Barut et al. (2011)
Output
Forage yield	kg	9.0	Moreno et al. (2011)

The energy amounts calculated for the inputs were categorized as direct, indirect, renewable, and nonrenewable energy. The indirect energy was determined with the sum of machinery, fertilizer, seed, and chemical energies, and direct energy was determined by the sum of human labor, diesel fuel oil, and irrigation energies. Moreover, while the sum of human labor and seed energies was considered renewable energy, the others were evaluated as nonrenewable energy (Lorzadeh et al., 2012).

Energy efficiency was evaluated in terms of energy ratio, energy intensity (also called specific energy), and energy gain (also known as net energy produced or net energy output) (Rathke et al., 2007; Banaeian and Zangeneh, 2011; Barut et al., 2011; Moreno et al., 2011).

The energy ratio (no unit) was determined by dividing the energy output by the energy input. Energy intensity (MJ/kg) represents total energy input per unit vetch forage yield equivalent. Energy gain (MJ/ha) is the difference between total output and total input energies (Rathke et al., 2007).

CO₂ emission was calculated with diesel fuel and lubricant oil consumptions by using the following equations (Öztürk et al., 2017a; Gungor et al., 2018; Küsek, 2018).

Diesel-based CO₂ emission (kg CO₂/ha) = Diesel fuel used (L/ha) × Heating value (0.0371 GJ/L) × Emission factor (74.01 kg CO₂/GJ)

Lubricant oil-based CO₂ emissions = Oil used (L/ha) × Heating value (0.0382 GJ/L) × Emission factor (73.28 kg CO₂/GJ)

Similarly, Filipovic et al. (2006) and Khaledian et al. (2014) reported that the combustion of one liter of diesel fuel resulted in an emission of 2.75 kg CO₂ (0.0371 × 74.01). Lubricant oil consumption was considered 4.5% of diesel fuel consumption (Gözübüyük et al., 2015).

Yield-scaled CO₂ emissions named as specific CO₂ emission (g CO₂/kg_yield) used to analyze the relationship between CO₂ emissions and crop production were calculated with the ratio of total CO₂ emissions (g CO₂/ha) and vetch forage yield (kg_yield/ha) (Gungor et al., 2018; Küsek, 2018).

Statistical analysis

The effects of different tillage-sowing practices on input and output energies, energy use efficiency, and CO₂ emissions were evaluated by variance (analysis of variance) analysis using JMP statistical software. Significant means were compared at the level of 0.05 with the LSD multiple comparison test.

Results and Discussion

Operational values

Average 3-year diesel fuel, human labor, and EFC values of the agricultural equipment used in four different tillage-sowing practices for Hungarian vetch production under irrigated and rainfed crop rotations are shown in Table 3. In both crop rotations, diesel fuel consumptions were the highest in CT (52.2 L/ha in irrigated rotation and 53.1 L/ha in rainfed rotation) and the lowest in NT practice (16.4 L/ha in irrigated rotation and 16.6 L/ha in rainfed rotation). This was manifested as 3.2-fold difference between fuel consumptions in CT and NT. While RT1 and RT2 practices consumed 30.2 and 30.8 L/ha fuel in irrigated rotation, respectively, the consumptions were 29.6 and 31.2 L/ha in rainfed rotation. These values also showed that the difference between the CT and RT practices was 1.7–1.8 times lower in favor of RT practices. The significant differences in fuel oil consumption under conventional and NT conditions have also been manifested by many researchers. According to an investigation by Sarauskis et al. (2012), the fuel consumption in CT-sowing systems was more than five times higher compared to zero tillage. Akbarnia and Farhani (2014) determined approximately four times higher fuel consumptions under CT practice in a wheat farm than with NT. Similarly, Filipović et al. (2004) reported that compared to the CT system, the NT system consumed 82.7% less fuel in a maize-winter wheat rotation. From the results of previous studies, it is seen that the no-till practice resulted in fuel savings close to or a bit higher than our findings. It is clear from our data that the moldboard plough equipment used in the CT practice consumed more fuel (25.5 L/ha in irrigated rotation and 23.9 L/ha in rainfed rotation) due to deep tillage compared to the other tillage equipments (Tables 1 and 3). As compatible with research findings mentioned above, Moitzi et al. (2014) determined linear increases in fuel consumption with increasing working depth of the moldboard plough used in the CT system. Namdari et al. (2011) indicated an increase in fuel consumption in deep plowing. Šarauskis et al. (2017) also measured increases ranging from 10.3% to 24.3% in hourly fuel consumption in increased soil depths up to 20 cm depending on the machine working speed.

The human labor need was the highest in moldboard plough application with the lowest EFC values in both crop rotations (Table 3). Therefore, the CT practice with the moldboard plough had the highest human labor or the lowest EFC values compared to other tillage-sowing practices. These study findings regarding savings incurred from machine working time in vetch production were very valuable because, while the area amounts tilled and planted per hour was 0.132 and 0.133 ha in the conventional practice, respectively, in irrigated and rainfed rotations, the NT practice manifested a value that was more than 4.5 times higher. The NT practice also provided approximately two times lower working time compared to reduced tillage practices in both rotations. Parallel to our findings, Sarauskis et al. (2012) and Moitzi et al. (2013) declared the greatest working time need in CT practice due to deep ploughing. Sessiz et al. (2008) presented better values because the NT practice decreased both fuel consumption and working time, and the values were five to six times lower than those of CT with ploughing.

In addition, our findings showed that fuel consumptions in deep plowing were lower in the rainfed conditions than in the irrigated (Table 3). Since vetch year follows fallow year, fuel consumption might decrease as a result of extra moisture accumulation in the soil during tillage in rainfed conditions. In line with this result, Nkakini and Vurasi (2015) indicated that energy spent during tillage operations decreases with the increase in soil moisture content.

Input and output energies and energy use efficiencies

The quantities of energy consumed in vetch production in CT, RT1, RT2, and NT practices showed that soil tillage-sowing practices significantly affected all energy inputs, except seed energy in both crop rotations (Table 5). The greatest total energy input was determined in the CT practice as 11827.45 MJ/ha under irrigated crop rotation, indicating a value 1.27 times higher compared to rainfed crop rotation. Total input energies in the irrigated rotation relative to the values in rainfed rotation were 1.44 times higher in RT1, 1.30 times higher in RT2, and 1.40 times higher in NT. This could be explained with less fertilization and no irrigation under the rainfed rotation conditions (Table 5).

Table 5.

The Input and Output Energy Amounts (MJ/ha) for the Vetch Produced Under Four Different Tillage-Sowing Practices in Two Crop Rotations

Input	Tillage-sowing practice
	CT	RT1	RT2	NT
		Irrigated crop rotation
Diesel fuel oil	2937.56 ± 29.56^a	1698.66 ± 21.96^c	1731.58 ± 15.24^b	922.47 ± 6.54^d
Human labor	24.96 ± 1.41^a	16.35 ± 0.69^b	15.68 ± 0.78^b	12.69 ± 0.35^c
Machinery	648.29 ± 38.44^a	374.52 ± 18.12^c	392.82 ± 21.14^bc	408.99 ± 13.30^b
Fertilizers	4650.09 ± 253.25^d	4704.23 ± 265.21^c	4932.11 ± 282.12^b	5106.45 ± 143.37^a
Seed	1300 ± 0	1300 ± 0	1300 ± 0	1300 ± 0
Irrigation^*	2266.55 ± 9.25^a	2177.22 ± 33.89^b	1796.83 ± 34.19^c	1548.90 ± 15.02^d
Chemical	0 ± 0^b	95.20 ± 0^a	95.20 ± 0^a	95.20 ± 0^a
Total input	11827.45 ± 304.54^a	10366.18 ± 279.06^b	10264.22 ± 324.52^c	9394.70 ± 145.09^d
Output	52214.12 ± 3602.67	54621.68 ± 3501.78	54709.25 ± 3805.06	51398.53 ± 2454.71
		Rainfed crop rotation
Diesel fuel oil	2989.57 ± 55.87^a	1656.76 ± 18.49^c	1751.05 ± 22.24^b	927.27 ± 12.89^d
Human labor	23.98 ± 0.57^a	15.16 ± 0.46^b	14.75 ± 0.67^b	12.06 ± 0.42^c
Machinery	628.14 ± 14.78^a	353.17 ± 12.80^c	377.84 ± 20.03^bc	392.08 ± 14.83^b
Fertilizers	4386.85 ± 152.03^a	3776.15 ± 142.62^c	4386.85 ± 152.03^a	4004.03 ± 96.64^b
Seed	1300 ± 0	1300 ± 0	1300 ± 0	1300 ± 0
Chemical	0 ± 0^b	95.20 ± 0^a	95.20 ± 0^a	95.20 ± 0^a
Total input	9328.54 ± 167.68^a	7196.44 ± 165.56^c	7925.69 ± 135.10^b	6730.64 ± 111.87^d
Output	36093.92 ± 1548.83^b	35155.16 ± 1202.33^b	35443.87 ± 1764.49^b	39916.36 ± 1284.30^a

The values marked with different superscript letters in each row are statistically different (p < 0.05).

Irrigation labor included.

The NT practice with the lowest energy consumption reduced the input energies by 20.6% (irrigated) and 27.8% (rainfed) compared to the CT because no soil tillage equipment was used and less energy was necessary for irrigation. Input energy saved in the NT practice of this study was low because Sørensen and Nielsen (2005) simulated that, compared to CT, the input energy of reduced tillage and NT can be 18–53% and 75–83% lower, respectively. Contrary to these study results, Šarauskis et al. (2014) determined a lower total energy input in maize cultivation. They obtained 10.5% less energy input value in NT compared to the conventional deep-ploughing tillage. Yousefi et al. (2019) also found a lower value of 10.7% in NT under wheat cultivation conditions.

The lowest consumption in all practices was obtained for human labor, except in the CT practice without the application of chemicals. A large proportion of input energy use was attributed to fertilizer. Considering irrigated crop rotation, the ratio of fertilizer energy to total energy consumed in vetch production was 39.3% in CT, 45.4% in RT1, 48.1% in RT2, and 54.4% in NT. This was followed by fuel oil and irrigation energies in the CT practice, irrigation and fuel oil energies in the RT1 and RT2 practices, and irrigation and seed energies in the NT practice (Fig. 2). Parallel results were also observed under rainfed crop rotation. While the fertilizer energy among inputs had the highest ratio (47% in CT, 52.5% in RT1, 55.3% in RT2, and 59.5 in NT) in all practices, fuel oil energy ranked as the second highest ratio (32% in CT, 23% in RT1, and 22.1% in RT2), except for the NT practice.

FIG. 2.

The percentage distribution of the energy consumed for vetch production in four different tillage-sowing practices under two crop rotations. CT, conventional tillage; NT, no-tillage; RT1, reduced tillage-I; RT2, reduced tillage-II.

The fertilizer energy was followed by seed energy (19.3%) in the NT practice (Fig. 2). The reason for chemical fertilizer energy being so high was due to the full application of chemical fertilizers to achieve maximum yields in the soils with poor fertility. Therefore, higher yields (output energies) could be obtained under irrigated rotation through the supporting effect of additional fertilizer relative to rainfed rotation (Table 5). Some previous studies revealed that fertilizer energy in crop production was the most dominant input compared to the others. The results of energy analysis of winter vetch (Vicia sativa L.) produced in dry conditions in Thrace region of Turkey displayed that the chemical fertilizer energy (52.8%) was the highest followed by diesel fuel energy (25.6%) (Baran, 2017). Chemical fertilizer energy had the highest portion (56%) of total energy inputs in maize production (Abdi et al., 2012).

While the fertilizer energy in the NT practice under the irrigated rotation was the highest, it was statistically lower in the rainfed rotation compared to the CT practice (Table 5). Higher fertilizer consumption in the irrigated rotation compared to rainfed rotation could be the result of higher soil water content that influences uptake of elements required in the irrigated plants (Xue et al., 2017). The NT practice in the rainfed rotation reduced the fertilizer need because the conservation tillage (minimum tillage, direct drilling, zero tillage, and so on) improves soil fertility due to increased soil organic matter from crop residue (Sharif et al., 2018).

The NT practice significantly decreased the requirements for direct (fuel oil+human labor+irrigation) and nonrenewable energies (fuel oil+machinery+fertilizers+irrigation+chemical) compared to reduced and CT practices (Fig. 3). Direct energy in the NT practice was reduced at a rate of 52.5% (irrigated) and 68.8% (rainfed) compared to the CT practice, which had the highest value. The nonrenewable energy in the NT practice was also 23.1% (irrigated) and 32.3% (rainfed) less compared to the CT practice. It could be argued that the reduction of fuel oil consumption using less tillage equipment reduced the direct and nonrenewable energies in conservation tillage conditions compared to CT.

FIG. 3.

Types of energy consumed in the vetch production in four different tillage-sowing practices under two crop rotations. The values marked with different lowercases in each crop rotation for each energy type are statistically different (p < 0.05).

The NT practice had the lowest renewable energy consumption (human labor and seed) in both rotations. Same seed and reduced human labor values provided similar renewable energy values for two crop rotations (Table 5). Indirect energy values (machinery+fertilizer+seed+chemical) in irrigated rotation in the NT practice increased, while they decreased in rainfed rotation (Fig. 3). Fertilizer energy was the most effective element in changing the indirect energy amount (Table 5). Therefore, the NT practice had the highest value in irrigated rotation, while the CT practice had the highest value in rainfed rotation.

Average values for 3 years (Table 5) showed that the output energy in rainfed rotation was significantly higher in the NT practice (39916.36 MJ/ha), a result of the higher vetch forage yields than for the conventional and reduced tillage practices. The energy output in the CT, RT1, and RT2 practices was 9.6, 11.9, and 11.2% lower than in the NT practice, respectively. Higher output energies were obtained in all tillage-sowing practices under irrigated crop rotation as a result of higher vetch forage yields compared to rainfed rotation, while tillage-sowing practices provided similar effects on the yields statistically (Table 5). The practices of CT, RT1, RT2, and NT in the irrigated rotation provided 1.45, 1.55, 1.54, and 1.29 times higher output energies, respectively, compared to rainfed rotation. These values indicated that the NT practice in rainfed conditions could be more appropriate to improve the vetch forage yield with more effective use of the soil water as a result of improved soil properties. Many previous studies have indicated that the NT practice has been a better alternative in terms of soil water conservation compared to the CT practice. According to Rusu (2014), using minimum and NT practices promotes the increase of soil organic matter content, aggregation, and permeability, and provide a greater water supply. Similarly, Yu et al. (2011) expressed that NT practice promotes available soil water by improving soil porosity and wet aggregate stability, and thereby increases crop yield. Rain water use efficiency has been reported to be higher under the NT practice compared to CT (Li et al., 2005). As a supporting important result for our study findings, Pittelkow et al. (2015) conducted an analysis on a global scale to evaluate the effects of numerous crops (50 crops) and environmental factors (63 countries) on NT compared to CT yields using data obtained from 678 different studies. The results of this analysis showed that no-till practice increases yields compared to CT under rainfed conditions in dry climates. Farooq et al. (2011) expressed that yields in conservation agriculture under rainfed conditions were often greater compared to CT.

The CT practice had a statistically lower energy ratio (4.41 in irrigated rotation and 3.87 in rainfed rotation) compared to the NT practice (5.47 in irrigated rotation and 5.93 in rainfed rotation) with the greatest energy ratio in both rotations (Fig. 4). Moreover, reduced tillage practices increased (∼21.0%) the energy ratio significantly compared to the CT practice. Therefore, the order of energy ratios for different tillage practices could be expressed as NT>RT>CT. Yousefi et al. (2019) also determined that the energy ratio amounts of different tillage systems followed the order of NT>RT>CT practices in wheat production. These findings show that energy ratio increased with decreasing soil tillage applications in both crop rotations. The use of more machinery and increased operational time increases energy consumption to a major degree and may reduce energy use efficiency. Similarly, Rathke et al. (2007) observed that the energy ratio tended to increase when soil tillage operations were reduced. Šarauskis et al. (2014) achieved the highest energy efficiency ratio in maize production with the NT practice and it resulted in a 12.9% higher value compared to conventional deep ploughing.

FIG. 4.

Energy ratio (output/input) values in the vetch production in four different tillage-sowing practices under two crop rotations. The values marked with different lowercases in each crop rotation are statistically different (p < 0.05).

Higher output energies, despite higher input energies in irrigated rotation, increased the energy ratio in the CT, RT1, and RT2 practices compared to rainfed rotation. However, an energy rate that was 8.4% higher was acquired with the NT practice with both the relative yield increase and input energy decrease in rainfed rotation compared to irrigated rotation (Table 5 and Fig. 4). Therefore, it could be said that this high energy ratio in the rainfed rotation corresponded to a high yield and low mechanization level. Taner et al. (2016) also expressed that higher energy use efficiency with minimum energy input and maximum output energy was determined in NT practice than CT and RT in the wheat production under wheat-fallow, wheat-chickpea, and wheat-wheat rotations in a rainfed region.

The greatest energy intensity was determined in the CT practice (2.04 MJ/kg in irrigated rotation and 2.33 MJ/kg in rainfed rotation), while conservation tillage positively affected energy intensity, and values were statistically lower than those in the CT practice (Fig. 5). The NT practice with minimum energy intensity resulted in 19.1% and 34.8% lower values than the CT practice in the irrigated and rainfed rotations, respectively. The finding for tillage practices is consistent with the finding of Tabatabaeefar et al. (2009), who emphasized that the minimum energy consumed in wheat production was 8.81 MJ/kg under the NT practice and that it was lower by 25.2% than with moldboard treatment. The change in trend for energy intensity in soil tillage-sowing practices in rainfed rotation was similar to changing trends of nonrenewable and direct energies (Figs. 3 and 5). Therefore, it could be asserted that less diesel fuel oil consumption in the conservation tillage practices is a more dominant input to obtain less energy intensity values in rainfed crop rotation (Table 5). Energy intensity values in irrigated rotation were lower than the values in rainfed rotation values, except in the NT practice (Fig. 5). Higher fertilizer consumption in irrigated rotation could deter obtaining lesser energy intensity values, despite higher forage yields.

FIG. 5.

Energy intensity values in the vetch production in four different tillage-sowing practices under two crop rotations. The values marked with different lowercases in each crop rotation are statistically different (p < 0.05).

Energy gain for different tillage practices in both rotations generally displayed similar trends to total energy output (Fig. 6 and Table 5). This finding is commensurate with the result that the energy gain manifested a behavior generally similar to that of energy output argued by Zentner et al. (2004) and Yousefi et al. (2019). This behavior also confirmed energy gain increases as long as the energy output per unit energy input increases (Moreno et al., 2011). Energy gain also differed between the crop rotations and it was lower in rainfed conditions. The decrease rates in the CT, RT1, RT2, and NT practices were 33.7%, 36.8%, 38.1%, and 21%, respectively. These results indicated that NT practice under rainfed conditions is more suitable compared to other tillage-sowing practices due to the increase in energy output and decrease in energy inputs.

FIG. 6.

Energy gain values in the vetch production in four different tillage-sowing practices under two crop rotations. The values marked with different lowercases in each crop rotation are statistically different (p < 0.05).

CO₂ emissions

Although total CO₂ emissions based on the heating value of diesel fuel and lubricant oil showed similar changes under the two crop rotations, tillage-sowing practices had a significant effect on CO₂ emission, and the highest amount of CO₂ emissions occurred in CT practice (Fig. 7). The conservation tillage practices in both crop rotations logarithmically (r² = 0.913 in irrigated rotation and r² = 0.898 in rainfed rotation) reduced the CO₂ emissions (Fig. 7). Carbon emissions from moldboard plough were 19.8 kg C/ha in irrigated rotation and 18.5 kg C/ha in rainfed rotation (the CO₂ emission was multiplied by 0.27 coefficient convert to C). Therefore, moldboard plowing in CT practice released CO₂ equivalent to 48.9% and 45.0% of total emission in irrigated and rainfed rotations, respectively. These values were high when considering the C emission equivalent values that ranged from 13.4 to 20.1 kg C/ha of the moldboard plowing given by Lal (2004). NT practice saved ∼69% of CO₂ emissions for irrigated and rainfed rotations, in comparison with CT practice, as a consequence of fuel savings.

FIG. 7.

CO₂ emission values in the vetch production in four different tillage-sowing practices under two crop rotations. The values marked with different lowercases in each crop rotation are statistically different (p < 0.05).

In accordance to an analysis of previous study findings, many studies reported close rates for CO₂ emissions from NT practice compared to CT. Khaledian et al. (2014) determined CO₂ emission up to 50% less in NT practice compared to CT, while Stajnko et al. (2009) found a reduction of 80%. Šarauskis et al. (2014) found that agricultural machinery used in NT practice in maize cultivation emits 57.7% less CO₂ gas into the environment compared to the emissions of conventional deep-ploughing tillage. Some of the previous studies reported excessively high CO₂ emission values for CT practices. In the seedbed preparation stage, Lal (2004) determined that CT resulted in 6 times higher carbon emission (35.3 kg C/ha) than NT. Filipovic et al. (2006) determined that, while CT practice in the production of four different crops (maize, wheat, barley, and soybean) released CO₂ quantities ranging from 132.36 kg CO₂/ha to 167.72 kg CO₂/ha based on the fuel consumption, the commensurate figures ranged from 15.95 to 20.21 kg CO₂/ha in the NT practice.

Reduced tillage-sowing practices also provided lower emissions ranging between 41% and 44% from those valid for the CT practice. Our results, which were higher than in a previous study finding that reported CO₂ emission rates in the production of four major crops (wheat, sugar beet, bean and potato), were reduced by 15–29% in the reduced tillage practice compared to the conventional practice (Koga et al., 2003).

Yield-indexed CO₂ emissions (specific CO₂ emission) were ∼1.5 times higher in CT, RT1, and RT2 practices under rainfed rotation than in irrigated rotation with higher vetch forage yields, while the NT practice revealed 1.3 times higher specific CO₂ emissions (Fig. 8). In both rotations, the NT practice had the lowest specific CO₂ emission, and emission values that were significantly lower at 68.8% (irrigated) and 72.1% (rainfed) than in the CT practice. It was determined that specific CO₂ emissions were reduced similar to the CO₂ emission logarithmically (r² = 0.921 in irrigated rotation and r² = 0.890 in rainfed rotation) in the conservation tillage practices under rainfed and irrigated rotations (Fig. 8).

FIG. 8.

Specific CO₂ emission values in the vetch production in four different tillage-sowing practices under two crop rotations. The values marked with different lowercases in each crop rotation are statistically different (p < 0.05).

Conclusions

These results reveal that the NT practice in rainfed and irrigated rotations was very advantageous compared to the CT practice in terms of saving both diesel fuel (3.2 times less) and working time (4.5 times less). Therefore, the greatest output/input energy ratio (5.47 in irrigated rotation and 5.93 in rainfed rotation) and the lowest energy intensity (1.65 MJ/kg in irrigated rotation and 1.52 MJ/kg in rainfed rotation) were determined in the NT practice. Energy gain in rainfed rotation, despite lower energy input, was lesser than in irrigated rotation with higher vetch yields. Conventional practice also consumed more fuel compared to the reduced tillage practices. Lower fuel consumption in conservation tillage practices sharply reduced CO₂ emissions. The NT practice reduced ∼69% of CO₂ emission compared to the CT practice.

It was concluded that NT practice in Hungarian vetch production in both irrigated and rainfed rotations can be an appropriate option to achieve higher energy use efficiency and lower CO₂ emissions from fuel oil consumption. Reduced tillage practices also can be considered a second option in Hungarian vetch production. Moreover, compared to the NT practice in rainfed rotation in semiarid climate conditions, NT practice in irrigated rotation would be more suitable due to both reduced yield-indexed CO₂ emissions and increased energy gain.

Footnotes

Author Disclosure Statement

No competing financial interests exist.

Funding Information

This research was financially supported by “General Directorate of Agricultural Research and Policies in Ministry of Agriculture and Forest in Turkey” (Project No. TAGEM-BB-980210K1).

References

Abdalla

, Chivenge

, Ciais

, and Chaplot

(2016). No-tillage lessens soil CO₂ emissions the most under arid and sandy soil conditions: Results from a meta-analysis. Biogeosciences, 13, 3619.

Abdi

, Hematian

, Shahamat

E.Z.

, and Bakhtiari

A.A.

(2012). Optimization of energy consumption pattern in the maize production system in Kermanshah province of Iran. Res. J. Appl. Sci. Eng. Tech. 4, 2548.

Akbarnia

, and Farhani

(2014). Study of fuel consumption in three tillage methods. Res. Agr. Eng. 60, 142.

Banaeian

, and Zangeneh

(2011). Study on energy efficiency in corn production of Iran. Energy, 36, 5394.

Baran

M.F.

(2017). Energy and economic analysis of vetch production in Turkey: A case study from Thrace region. Fresenius Environ. Bull. 26, 1966.

Barut

Z.B.

, Ertekin

, and Karaagac

H.A.

(2011). Tillage effects on energy use for corn silage in Mediterranean Coastal of Turkey. Energy, 36, 5466.

Busari

M.A.

, Kukal

S.S.

, Kaur

, Bhatt

, and Dulazi

A.A.

(2015). Conservation tillage impacts on soil, crop and the environment. Int. Soil Water Con. Res. 3, 119.

Dalias

(2012). Increased yield surplus of vetch-wheat rotations under drought in a Mediterranean environment. Sci. World J. 2012, 658518.

Eastern Anatolia Agricultural Research Institute (DATAE). (2016). Hydro-meteorological observation data. Erzurum: Eastern Anatolia Agricultural Research Institute.

10.

Eastern Anatolia Project (DAP). (2014). Eastern Anatolia Project (DAP) Action Plan (2014–2018) [in Turkish]. Erzurum: DAP Regional Development Administration. Available at: www.dap.gov.tr/dap-eylem-plani/eylem-plani (accessed February 27, 2019).

11.

Environmental Protection Agency (EPA). (2019). Global Greenhouse Gas Emissions Data. United States Environmental Protection Agency. Available at: www.epa.gov/ghgemissions/global-greenhouse-gas-emissions-data (accessed October 13, 2019).

12.

Farooq

, Flower

K.C.

, Jabran

, Wahid

, and Siddique

K.H.M.

(2011). Crop yield and weed management in rainfed conservation agriculture. Soil Till. Res. 117, 172.

13.

Filipović

, Košutić

, and Gospodarić

(2004). Influence of different soil tillage systems on fuel consumption, labour requirement and yield in maize and winter wheat production. Poljoprivreda, 10, 17.

14.

Filipovic

, Kosutic

, Gospodaric

, Zimmer

, and Banaj

(2006). The possibilities of fuel savings and the reduction of CO₂ emissions in the soil tillage in Croatia. Agr. Ecosyst. Environ. 115, 290.

15.

Gözübüyük

, Çelik

, Öztürk, İ., Demir

, and Adıgüzel

M.C.

(2012). Comparison of energy use efficiency of various tillage-seeding systems in prodction of wheat [in Turkish]. J. Agr. Machin. Sci. 8, 29.

16.

Gözübüyük

, Öztürk, İ., Çelik

, Evren

, Daşçı

, and Adıgüzel

M.C.

(2015). Comparison of various tillage-seeding systems in terms of energy use efficiency in production of sunflower [in Turkish]. J. Agr. Machin. Sci. 11, 113.

17.

Gungor

, Kusek

, Kucukerdem

H.K.

, Ozturk

H.H.

, and Akdemir

(2018). Carbon dioxide emissions related to fuel consumption for groundnut production in Turkey. In: Vîrsta

Ed., Land Reclamation, Earth Observation and Surveying, Environmental Engineering, Vol VII, Scientific papers, Series E. Bucharest, Romania: CERES Publishing House, p. 1.

18.

Hamzei

, and Seyyedi

(2016). Energy use and input–output costs for sunflower production in sole and intercropping with soybean under different tillage systems. Soil Till. Res. 157, 73.

19.

Hanna

(2016). Estimating the Field Capacity of Farm Machines. Ames, IA: Iowa State University. Available at: www.extension.iastate.edu/agdm/crops/html/a3-24.html (accessed February 28, 2019).

20.

Houshyar

(2017). Environmental impacts of irrigated and rain-fed barley production in Iran using life cycle assessment (LCA). Spanish J. Agr. Res. 15, e0204.

21.

Huynh

H.T.

, Hufnagel

, Wurbs

, and Bellingrath-Kimura

S.D.

(2019). Influences of soil tillage, irrigation and crop rotation on maize biomass yield in a 9-year field study in Müncheberg, Germany. Field Crop. Res. 241, 107565.

22.

Jaiswal

, and Agrawal

(2019). Carbon footprints of agriculture sector. In: Muthu

S.S.

Ed., Carbon Footprints. Case Studies from the Building, Household, and Agricultural Sectors. Springer, Singapore, p. 81.

23.

Karaağaç

H.A.

, Aykanat

, Gültekin

, and Baran

M.F.

(2014). Determination of energy using efficiency at corn production in Adana. J. Tekirdag Agr. Fac. 11, 75.

24.

Karayel

, and Šarauskis

(2019). Environmental impact of no-tillage farming. Environ. Res. Eng. Manag. 75, 7.

25.

Khaledian

, Mailhol

J.C.

, and Ruelle

(2014). Diesel oil consumption, work duration, and crop production of corn and durum wheat under conventional and no-tillage in southeastern France. Arch. Agron. Soil Sci. 60, 1067.

26.

Kizilaslan

(2009). Input–output energy analysis of cherries production in Tokat province of Turkey. Appl. Energ. 86, 1354.

27.

Koga

, Tsuruta

, Tsuji

, and Nakano

(2003). Fuel consumption-derived CO₂ emission under conventional and reduced tillage cropping systems in northern Japan. Agr. Ecosyst. Environ. 99, 213.

28.

Kumar

, Saharawat

Y.S.

, Gathala

M.K.

, Jat

A.S.

, Singh

S.K.

, Chaudhary

, and Jat

(2013). Effect of different tillage and seeding methods on energy use efficiency and productivity of wheat in the Indo-Gangetic Plains. Field Crop. Res. 142, 1.

29.

Kumlay

A.M.

, Olgun

, Şanal

, and Turgut

(2007). The effect of the first tillage times and rotation systems on productivity of wheat (T. aestivum L.). Lucrări Ştiinţifice, 50, 257.

30.

Küsek

(2018). Assessment of carbon dioxide emissions due to fuel consumption in lentil production in Southeastern Anatolia Region. Harran J. Agr. Food Sci. 22, 572.

31.

Lal

(2004). Carbon emission from farm operations. Environ. Int. 30, 981.

32.

Lekavičienė

, Šarauskis

, Naujokienė

, Buragienė

, and Kriaučiūnienė

(2019). The effect of the strip tillage machine parameters on the traction force, diesel consumption and CO₂ emissions. Soil Till. Res. 192, 95.

33.

L.L.

, Huang

G.B.

, Zhang

R.Z.

, Jin

X.J.

, Li

G.D.

, and Chan

K.Y.

(2005). Effects of conservation tillage on soil water regimes in rainfed areas. Acta Ecol. Sin. 25, 2326.

34.

, Baležentis

, Makutėnienė

, Streimikiene

, and Kriščiukaitienė

(2016). Energy-related CO₂ emission in European Union agriculture: Driving forces and possibilities for reduction. Appl. Energ. 180, 682.

35.

López-Vázquez

, Cadena-Zapata

, Campos-Magaña

, Zermeño-Gonzalez

, and Mendez-Dorado

(2019). Comparison of energy used and effects on bulk density and yield by tillage systems in a semiarid condition of Mexico. Agronomy, 9, 189.

36.

Lorzadeh

S.H.

, Mahdavidamghani

, Enayatgholizadeh

M.R.

, and Yousefi

(2012). Research of energy use efficiency for maize production systems in Izeh, Iran. Acta Agr. Sloven. 99, 137.

37.

, and Lu

(2017). Tillage and crop residue effects on the energy consumption, input–output costs and greenhouse gas emissions of maize crops. Nutr. Cycl. Agroecosyst. 108, 323.

38.

Mangalassery

, Sjögersten

, Sparkes

D.L.

, Sturrock

C.J.

, Craigon

, and Mooney

S.J.

(2014). To what extent can zero tillage lead to a reduction in greenhouse gas emissions from temperate soils? Sci. Rep. 4, 4586.

39.

Moitzi

, Szalay

, Schüller

, Wagentristl

, Refenner

, Weingartmann

, Liebhard

, Boxberger

, and Gronauer

(2013). Effects of tillage systems and mechanization on work time, fuel and energy consumption for cereal cropping in Austria. Agric. Eng. Int. CIGR J. 15, 94.

40.

Moitzi

, Wagentristl

, Refenner

, Weingartmann

, Piringer

, Boxberger

, and Gronauer

(2014). Effects of working depth and wheel slip on fuel consumption of selected tillage implements. Agric. Eng. Int. CIGR J. 16, 182.

41.

Moreno

M.M.

, Lacasta

, Meco

, and Moreno

(2011). Rainfed crop energy balance of different farming systems and crop rotations in a semi-arid environment: Results of a long-term trial. Soil Till. Res. 114, 18.

42.

Namdari

, Rafiee

, and Jafari

(2011). CO₂ emission as a result of the fuel consumption and tillage quality in different tillage conditions. Int. J. Environ. Sci. 1, 1659.

43.

Nkakini

S.O.

, and Vurasi

N.M.

(2015). Effects of moisture content, bulk density and tractor forward speeds on energy requirement of disc plough. Int. J. Adv. Res. Eng. Tech. 6, 69.

44.

Olgun

, Serin

, Kumlay

A.M.

, and Turgut

(2007). The effects of tillage and rotation systems in vetch (Vicia pannonica) yield, some yield components and soil characters [in Turkish]. Presented at the Turkey VII. Field crops congress, Erzurum, Turkey, June 25–27.

45.

Oliver

J.G.J.

, and Peters

J.A.H.W.

(2018). Trends in Global CO₂ and Total Greenhouse Gas Emissions: 2018 Report. PBL Netherlands Environmental Assessment Agency, The Hague, Netherlands, Publication number: 3125.

46.

Özden

D.M

. (1995). Time Study Analysis and Database Generation in Agricultural Mechanization. General Directorate of Rural Services, Soil and Water Resources Research Department, Ankara, Turkey, Publication No. 81.

47.

Özgül

(2003). Classifying and mapping of great soil groups commonly found in Erzurum [in Turkish]. PhD thesis. Atatürk University, Graduate School of Natural and Applied Sciences, Erzurum.

48.

Öztürk

H.H.

, Gözübüyük

, and Atay, Ü. (2017a). An assessment of carbon dioxide emissions related to fuel consumption for cotton production in Turkey. Presented at the 3rd ASM International Congress of Agriculture and Environment, Antalya, Turkey, November 16–18.

49.

Öztürk

M.Z.

, Çetinkaya

, and Aydın

(2017b). Climate types of Turkey according to Köppen-Geiger climate classification [in Turkish]. Istanbul Univ. J. Geo. 35, 17.

50.

Pittelkow

C.M.

, Linquist

B.A.

, Lundy

M.E.

, Liang

, van Groenigen

K.J.

, Lee

, van Gestel

, Six

, Venterea

R.T.

, and van Kessel

(2015). When does no-till yield more? A global meta-analysis. Field Crop. Res. 183, 156.

51.

Platis

D.P.

, Anagnostopoulos

C.D.

, Tsaboula

A.D.

, Menexes

G.C.

, Kalburtji

K.L.

, and Mamolos

A.P.

(2019). Energy analysis, and carbon and water footprint for environmentally friendly farming practices in agroecosystems and agroforestry. Sustainability, 11, 1664.

52.

Rathke

G.W.

, Wienhold

B.J.

, Wilhelm

W.W.

, and Diepenbrock

(2007). Tillage and rotation effect on corn–soybean energy balances in eastern Nebraska. Soil Till. Res. 97, 60.

53.

Rusu

(2014). Energy efficiency and soil conservation in conventional, minimum tillage and no-tillage. Int. Soil Water Con. Res. 2, 42.

54.

Sainju

U.M.

(2016). A global meta-analysis on the impact of management practices on net global warming potential and greenhouse gas intensity from cropland soils. PLoS One, 11, e0148527.

55.

Šarauskis

, Buragienė

, Masilionytė

, Romaneckas

, Avižienytė

, and Sakalauskas

(2014). Energy balance, costs and CO₂ analysis of tillage technologies in maize cultivation. Energy, 69, 227.

56.

Sarauskis

, Buragiene

, Romaneckas

, Sakalauskas

, Jasinskas

, Vaiciukevicius

, and Karayel

(2012). Working time, fuel consumption and economic analysis of different tillage and sowing systems in Lithuania. Presented at the 18th International Scientific Conference, Engineering for Rural Development, Jelgava, Latvia, May 24–25.

57.

Šarauskis

, Vaitauskienė

, Romaneckas

, Jasinskas

, Butkus

, and Kriaučiūnienė

(2017). Fuel consumption and CO₂ emission analysis in different strip tillage scenarios. Energy, 118, 957.

58.

Sayed

, Sarker

, Kim

J.E.

, Rahman

, and Mahmud, Md.G.A. (2019). Environmental sustainability and water productivity on conservation tillage of irrigated maize in red brown terrace soil of Bangladesh. J. Saudi Soc. Agr. Sci. DOI: 10.1016/j.jssas.2019.03.002.

59.

Sessiz

, Sogut

, Alp

, and Esgici

(2008). Tillage effects on sunflower (Helianthus annuus, L.) emergence, yield, quality, and fuel consumption in double cropping system. J. Central Eur. Agr. 9, 697.

60.

Sharif

, Ijaz

S.S.

, Ansar

, Ahmad

, and Sadiq

S.A.

(2018). Evaluation of conservation tillage system performance for rainfed wheat production in upland of Pakistan. Pakistan J. Agr. Res. 31, 37.

61.

Sørensen

C.G.

, and Nielsen

(2005). Operational analyses and model comparison of machinery systems for reduced tillage. Biosyst. Eng. 92, 143.

62.

Stagnari

, Maggio

, Galieni

, and Pisante

(2017). Multiple benefits of legumes for agriculture sustainability: An overview. Chem. Biol. Technol. Agric. 4, 2.

63.

Stajnko

, Lakota

, Vučajnk

, and Bernik

(2009). Effects of different tillage systems on fuel savings and reduction of CO₂ emissions in production of silage corn in Eastern Slovenia. Polish J. Environ. Stud. 18, 711.

64.

Tabatabaeefar

, Emamzadeh

, Varnamkhasti

M.G.

, Rahimizadeh

, and Karimi

(2009). Comparison of energy of tillage systems in wheat production. Energy, 34, 41.

65.

Taner

, Kaya

, Arısoy

R.Z.

, Gültekin, İ., and Partigöç

(2016). Effect of tillage systems on energy use efficiency in wheat based cropping sequence. Int. J. Agric. Biol. 18, 353.

66.

Taş

(2010). Determination of optimum mixture rate and cutting time for vetch+wheat mixtures sown in spring and autumn under irrigated conditions I. hay yield and yield components. Anadolu J. AARI, 20, 45.

67.

Xi-Liu

, and Qing-Xian

(2018). Contributions of natural systems and human activity to greenhouse gas emissions. Adv. Clim. Change Res. 9, 243.

68.

Xue

, Shen

, and Marschner

(2017). Soil water content during and after plant growth influence nutrient availability and microbial biomass. J. Soil Sci. Plant Nutr. 17, 702.

69.

Yousefi

, Khoramivafa

, Damghani

A.M.

, Mohammadi

, and Alagha

A.B.

(2019). Soil tillage systems impact on energy use pattern and economic profitability in wheat agroecosystems. Mod. Concept Dev. Agron. 3, 1.

70.

, Peng

, Ma

, and Zhang

(2011). Effects of no-tillage on soil water content and physical properties of spring corn fields in semiarid region of northern China. Chinese J. Appl. Ecol. 22, 99.

71.

Zentner

R.P.

, Lafond

, Derksen

D.A.

, Nagy

C.N.

, Wall

D.D.

, and May

W.E.

(2004). Effects of tillage method and crop rotation on non-renewable energy use efficiency for a thin Black Chernozem in the Canadian Prairies. Soil Till. Res. 77, 125.

Tillage and Irrigation Impacts on the Efficiency of Fossil Fuel Utilization for Hungarian Vetch Production and Fuel-Related CO 2 Emissions

Abstract

Introduction

Materials and Methods

Experiment area

Experimental design and agricultural operations

Determination of operational values, input and output energies, energy efficiency, and CO2 emission

Statistical analysis

Results and Discussion

Operational values

Input and output energies and energy use efficiencies

CO2 emissions

Conclusions

Footnotes

Author Disclosure Statement

Funding Information

References

Determination of operational values, input and output energies, energy efficiency, and CO₂ emission

CO₂ emissions