Decreased tillage intensity can contribute to a reduced agro-technological footprint and stabilise the negative impact of climate change, especially in leguminous crop cultivation. For this reason, a long-term (since 1988) stationary field experiment has been performed on silty loam Planosol (in Lithuania). The main objective of this study was to establish the influence of sustainable tillage and no-tillage systems on soil aggregate stability to water, penetration resistance, enzymatic activity, abundance of earthworm and faba bean grain yield. Five different tillage systems were investigated: conventional deep and shallow mouldboard ploughing, deep chiselling, shallow disking and no-tillage. No-tillage in faba bean cultivation significantly increased soil structural stability by 40–97%, saccharase content by 0.7–2.0 times, urease activity by 3–4 times, the average quantity of earthworm by 55% and the biomass by 3.6 times. The impact of other ploughless tillage systems on soil properties was positive but not as significant. Faba bean grain yield was more influenced by growing seasons than by different tillage methods.

No abstract

Nowadays the priority in agriculture is given to the soil tillage systems which enable reduction of organic matter decomposition. Our investigation was aimed to assess the long-term impact of reduced intensity tillage systems, straw and green manure combinations on soil organic matter quantity and quality. Since 1999, a long-term field experiment has been done at the Experimental Station of Aleksandras Stulginskis University (former Lithuanian University of Agriculture) at 54º52′50′′ N latitude and 23º49′41′′ E longitude. The results presented in this paper were obtained in the 12 th and 14 th years of investigations. The soil of the experimental site is Epieutric Endocalcaric Endogleyic Planosol. Continuous long-term (12 and 14 years) straw application increased soil organic carbon (SOC) content by 9.3% and 12.0% compared with the plots without straw. Reduced tillage systems without primary tillage (shallow rotovating before sowing, catch cropping for green manure with rotovating, no-tillage) were even more effective. Compared with conventional ploughing, SOC increased by 19.4% to 33.9%. These tillage systems increased soil quality too, since SOC stratification ratio between 0-10 and 10-20 cm layers increased by 1.14 till 1.21. Reduced tillage systems with primary tillage (shallow ploughing and shallow loosening) had no effect both on SOC and stratification process in the soil. SOC pools over the experimental years tended to increase by 9.3% and 11.6% in the treatments of long-term application of straw compared with the plots without straw. Notillage and catch cropping for green manure with rotovating compared with conventional ploughing significantly increased the pools of organic carbon by 31.7% to 33.3% in the plots without straw and by 28.9% to 32.7% in the plots with straw. Continuous straw application increased the quantity of mobile humus substances by 22.7% compared to the plots without straw. Straw in combination with catch crop for green manure incorporation and rotovating and no-tillage increased mobile humus substances by 53.2% and 58.8% compared with conventional ploughing. Only long-term application of straw increased the quantity of mobile humic acids by 40.6% compared with the plots without straw. The rate of mobile humic acids from total amount of mobile humus substances in the treatments without straw amounted to 39.8%, while with straw this content increased to 45.6%. Reduced tillage systems without primary tillage had no significant effect on mobile humic acids but tended to increase soil organic matter quality.

Please use the following format when citing the article: Bogužas V., Sinkevičienė A., Romaneckas K., Steponavičienė V., Skinulienė L., Butkevičienė L. M. 2018. The impact of tillage intensity and meteorological conditions on soil temperature, moisture content and CO 2 efflux in maize and spring barley cultivation. Zemdirbyste-Agriculture, 105 (4): 307-314. AbstractWith a worldwide increase in the use of sustainable tillage systems, it is important to ascertain their long-term effects on soil properties and greenhouse gas emissions. However, there are not many long-term experiments of this type, and they are conducted in very different climatic and soil conditions. To fill a knowledge gap in this field of study, a long-term, stationary field experiment was set up at Aleksandras Stulginskis University's Experimental Station (54°52ʹ57 N lat., 23°50ʹ51 E long.) in 1988. The current paper presents the experimental data from the 2015-2016 period. The soil of the experimental site is Epieutric Endocalcaric Endogleyic Planosol (PL.gln-can-eup) with a texture of loam on heavy loam. The topsoil layer's characteristics are as follows: pH KCL 6.6-7.0, available phosphorus (P 2 O 5 ) content 131.1-206.7 mg kg -1 , available potassium (K 2 O) content 72.0-126.9 mg kg -1 , humus content 1.68%. This study set out to investigate the effects of long-term application of different tillage systems and meteorological conditions on soil temperature, moisture content and soil surface carbon dioxide (CO 2 ) efflux in the stands of maize and spring barley. The experiment included the following primary tillage methods differing in intensity: 1) conventional ploughing (CP) at a 23-25 cm depth (control treatment), 2) shallow ploughing (SP) at a depth of 12-15 cm, 3) deep cultivation (DC) at a depth of 23-25 cm, 4) shallow cultivation (SC) at a depth of 12-15 cm and 5) no tillage (NT) (direct drilling). The findings of the study suggest that the soil surface CO 2 efflux depended on the amount of rainfall during the crop growing season. In a dry year 2016, the soil CO 2 efflux was lower than that in a wet year, the differences between the tillage treatments were more distinct, with the least flux being from the NT treatment. No significant differences among the tillage treatments were determined in a wet year 2015. The soil temperature depended on the tillage intensity and the weather conditions during the crop growing season. A lower soil temperature was recorded in the reduced tillage treatments compared with conventional tillage treatments. A negative strong correlation was established between the soil surface CO 2 efflux and soil temperature (y = 13.93867 + 0.303x; r = −0.96, P < 0.05). The tillage methods of different intensity did not have significant effect on the moisture content in the soil surface layer; however, in a dry year, the highest moisture content was determined in the no-tillage treatment, while in a wet year the differences were negligible.

Differently tilled faba bean cultivations, in particular, require a comprehensive study of weed diversity, abundance, and seedbank due to the lack of experimental data. Therefore, in 2016–2018, field trials were conducted at Vytautas Magnus University on the basis of a long-term tillage experiment. Conventional deep and shallow plowing, deep chiseling, shallow disking, and no-tillage systems were investigated. According to the results of the investigations, the air temperature and amount of precipitation during the vegetative season had a greater influence on the total number of weeds (r = 0.538 and 0.833 p > 0.05) than the types of tillage systems investigated. However, on average, a reduction in tillage intensity did not change the weed number, especially in disked and not tilled plots. On average, the biomass of weeds varied little between the treatments (from 105.9 to 125.7 g m−2) and mainly depended on the volume of forecrop residues (rannual = −0.982 p ≤ 0.01 and rperennial = 0.890 p ≤ 0.05). Higher total weed seedbanks were found in the disked (+43.0%) and not tilled (+21.6%) soils compared to deeply plowed ones. The weed seedbank was almost similarly distributed between the treatments, irrespective of the tillage depth and method used.