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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.

There is a lack of research on the practice of intercropping sugar beet and the impact of such agrocenoses on soil and crop fertility, especially under organic farming conditions. For this reason, a three-year stationary field experiment was performed at Vytautas Magnus University, Agriculture Academy, Lithuania. Sugar beet was grown continuously with intercropped Persian clover (Trifolium resupinatum L., MC), white mustard (Sinapis alba L., MM) and spring barley (Hordeum vulgare L., MB) as a living mulch. Inter-row loosening (CT) and mulching with ambient weeds (MW) were used as comparative treatments. The results showed that, under minimal fertilization, CT and intercropping increased the average content of nitrogen, phosphorus and potassium in the soil. However, the average content of magnesium was reduced in single cases (MW, MB), and the average content of sulphur was reduced in all cases. Intercropping significantly decreased the yields of sugar beet root-crop, but was mainly neutral in quality terms. The meteorological conditions during experimentation had a weak impact on root-crop quantity and quality. Generally, the practice of sugar beet intercropping requires more detailed research on how to minimize the competition between the sugar beet, living mulch and weeds, and how to balance the nutrition conditions.

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.

A long-term field experiment (since 1988) was carried out at the experimental station of the Aleksandras stulginskis university (Asu, 54º52′ N, 23º49′ e) in the conditions of transitional maritime-climate. Research data from the 2010-2012 experimental period are presented. the soil of the experimental site is silty light loam Endohypogleyic-Eutric Planosol (PLe-gln-w). Average annual temperature is 6.2°c. the aim of the experiment was to establish the influence of reduced primary autumn soil tillage on maize productivity. the treatments of the experiment were: 1) conventionally (22-25 cm) ploughed by a mouldboard plough, 2) shallowly (12-15 cm) ploughed by a mouldboard plough, 3) deeply (25-30 cm) tilled by a chisel cultivator, 4) shallowly (10-12 cm) tilled by a disc harrow, 5) no-till. the experimental results showed that all primary soil tillage methods (except for chiselling) normally had insignificant effect on maize biometric parameters. Deep chiselling had consistent negative influence on the biometric parameters of maize canopy, while no no-till effect was insignificantly positive. maize crop biometric parameters partially depended on weed infestation at the beginning and the end of maize vegetation. in two out of three experimental years, maize crop density at the beginning and end of vegetation did not differ significantly in differently tilled plots. A relationship was found between the number of annual as well as total number of weeds and crop density at the beginning of vegetation (r = −0.926** and −0.948**). crop density at the beginning of vegetation had significant positive effect on most maize productivity parameters. Reduced soil tillage from shallow ploughing to no-till had total positive effect on maize productivity in 2011 only because of the lower weed infestation. Relationships were established between weed infestation and maize crop productivity parameters (correlation coefficients from −0.394 to −0.965**). Productivity parameters were influenced by biometric parameters too (correlation coefficients from 0.713** to 0.920**).