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Cotton is an important cash crop in Xinjiang, accounting for 90.2% of China's total production in 2022. However, natural factors such as drought, high soil salinity, and the constraints of perennial shallow tillage soil management practices limit the yield and efficiency of cotton production and sustainable agricultural development. Deep vertical rotary tillage facilitates the breaking up of soil solidification and promotes the salt leached by irrigation water. In order to investigate the improvement effect of deep vertical rotary tillage on heavily saline cotton fields in Southern Xinjiang of China, this study conducted a 2 a (2021-2022) field experiment with three deep vertical rotary tillage depths (DT20: deep vertical rotary tillage 20 cm, DT40: deep vertical rotary tillage 40 cm, DT60: deep vertical rotary tillage 60 cm), and alternate with conventional tillage (five-share plowing 20 cm CT20), and CT20 was set to be the two consecutive years of conventional tillage. Original soil samples from 0-60 cm were collected to determine the water-stable aggregates. Soil moisture, salinity, organic carbon, total nitrogen, total phosphorus and total potassium were defermined by samples under the drip irrigation tapes, wide rows and narrow rows of each treatment on the 3rd day after each irrigation. Cotton root samples were collected at 105 days after sowing in 2021 and at 103 days in 2022. The effects of different depths of deep vertical rotary tillage on soil physical properties, soil nutrient content, cotton root length density, boll weight, dry matter mass accumulation and seed cotton yield were investigated, and the effect of crop yield was quantified by structural equation modeling. The results showed that: 1) deep vertical rotary tillage was able to loosen the soil in the tillage layer to optimize the soil structure. DT60 treatment was able to significantly reduce the soil bulk density, the content of coarse aggregates (>2 mm), and silt and clay particle (<0.053 mm) in the tillage depth layer compared with DT20 and CT20 treatment, which led to a significant reduction in mean weight diameter and mean geometric diameter, and increased total soil porosity and the content of micro-aggregates (<0.25～ 0.053 mm), while DT60 treatment was unable to further improve the soil structure in the deep soil layer compared with DT40 treatment. 2) DT40 and DT60 treatments were able to significantly increase soil moisture from 0-40 cm soil layer and reduce soil salinity and pH value, whereas DT20 treatment was only able to reduce soil salinity from 0-20 cm soil layer, whereas DT60 treatment was able to significantly reduce soil salinity and pH value from 0-60 cm soil layer compared with DT40 treatment. The reduction of soil salinity promoted the accumulation of soil organic carbon in the 0-40 cm soil layer and soil total nitrogen in the 0-60 cm soil layer, but DT60 treatment was unable to significantly increase soil organic carbon and soil total nitrogen in the 0-20 cm soil layer compared with the DT40 treatment. 3) The analysis of the structural equation modeling showed that soil salinity was an indirect factor affecting the seed cotton yield, and the accumulation of cotton’s dry matter and the weight of cotton bolls were the direct factored. The reduction of soil salinity favors soil nutrient accumulation and cotton root growth, promoted nutrient transport and accumulation to the plant organ, and increased cotton dry matter accumulation and seed cotton yield. Therefore, DT60 treatment had the best effect of soil salinity reduction, and thus the effect of yield increase. Comprehensive analysis showed that the depth of 60 cm on deep vertical rotary tillage with conventional tillage alternating can realize the synergy of improving and increasing the yield and efficiency of the severe saline cotton fields in the Southern Xinjiang of China. [ABSTRACT FROM AUTHOR]

Soil tillage is widely acknowledged to affect soil characteristics and agricultural productivity. This research investigates the short‐term effects of various tillage methods on soil physical properties and crop yields at a Central German field site with a dry climate (mean temperature 9.5°C; annual precipitation 470 mm). Three tillage approaches were evaluated: conventional plough tillage (25 cm depth), cultivator tillage (18 cm depth), and double‐layer plough tillage (15 and 30 cm depth). We assessed soil physical properties through standard laboratory analyses, compression tests, soil pore structure via X‐ray computed tomography (X‐ray CT) and crop yields over 3 years. The results indicate that cultivator tillage approach increased soil bulk density relative to conventional tillage, especially in the second year, though this effect diminished over time. Double‐layer plough tillage emerged as a viable short‐term alternative to conventional tillage, achieving comparable soil bulk density. Saturated hydraulic conductivity values were generally higher for soils under conventional tillage or double‐layer plough tillage than for cultivator tillage, highlighting their soil loosening effect. Classical soil analysis methods combined with X‐ray computed tomography provided valuable insights into tillage induced changes to soil structure. Cultivator tillage resulted in a distinct pore structure with reduced macroporosity and pore connectivity. Despite notable soil property variations, crop yields remained consistent across the tillage methods. Overall, double‐layer plough tillage presents a sustainable option, moderately improving soil physical properties while maintaining crop yields. This study highlights the need to assess the short‐term effects of tillage on soils and contributes to the broader dialogue on optimizing tillage strategies for effective soil management and crop production. [ABSTRACT FROM AUTHOR]

A field experiment was conducted in northeast China to examine the response of nitrogen cycling enzymes, that is, protease, N‐acetyl‐β‐D‐glucosaminidase (NAG), amidase, urease, and peptidase, as well soil organic nitrogen (SON) fractions and their relationships to RT (no maize residue application), NT (no tillage with maize residues placed on the surface), TT (plow maize residues into the soil at 0–35 cm depth in the first year, 0–20 cm in the second year, and 0–15 cm in the third year), and PT (plow maize residues into soil at 0–35 cm depth). The results have shown that NT significantly enhanced the activities of protease and NAG at 0–10 cm soil depth in comparison with other treatments. NT and TT significantly enhanced the activities of protease compared to RT and PT at 10–20 cm soil depth. TT significantly enhanced the activities of NAG in comparison with RT at 10–20 cm soil depth. TT and PT significantly enhanced the activities of NAG and peptidase compared to RT and NT at 20–35 cm soil depth. PT significantly increased the activities of protease in comparison with RT at 20–35 cm soil depth. NT, TT, and PT significantly enhanced the activities of peptidase compared to RT at 10–20 cm soil depth. NT significantly increased the concentration of hydrolyzable NH4+‐N$$ {\mathrm{NH}}_4^{+}\hbox{-} \mathrm{N} $$ in comparison with other treatments at 0–10 cm soil depth. PT significantly enhanced the concentration of hydrolyzable NH4+‐N$$ {\mathrm{NH}}_4^{+}\hbox{-} \mathrm{N} $$ and amino acid N compared to other treatments at 20–35 cm soil depth. Redundancy analysis showed that protease played a crucial role in the cycling of SON under RT and NT, whereas peptidase and NAG played a significant role in the cycling of SON under TT and PT, respectively. This study provided a comprehensive understanding of crop residue return methods for regulating soil N cycling. [ABSTRACT FROM AUTHOR]

Historical depletion of agricultural soils must be remedied to maintain their long-term food production function, including soils in intensive vineyards traditionally kept without plant cover to limit resource competition. This paper reports on the impact of five contrasting soil management regimes on indicators of soil quality such as soil organic carbon, nitrogen and their indices. We exposed sandy loam Rendzic Leptosol under a vineyard in Nitra-Dražovce (Slovakia, central Europe) to the following five treatments for 14 years: no-till sward, no-till sward+NPK100, no-till sward+NPK125, plowed tillage and (5) plowed tillage+manure. We found that grass swards continuously increased the total soil organic carbon in the topsoil, but plowed tillage resulted in no change. The availability of potentially mineralizable nitrogen was also increased by grass cover; but was not modified by manure but by mineral fertilizer addition. We tested the usefulness of carbon and management indices as indicators of changing soil C and N status and found them no better than tracking total and labile forms of both elements. In conclusion, the recovery of degraded vineyard soils under no-till grass sward cover is detectable within 14 years and is not affected by fertilization or manure addition. [ABSTRACT FROM AUTHOR]

The rice-ratoon system has long been considered an important economic, time-saving, and labor-saving planting method. Optimal tillage and straw management are beneficial to increasing the growth and yield of recycled rice. However, there is little research on the physical and chemical properties of soil under tillage and straw management, and its effects on the yield and fertilizer utilization of recycled rice. A field experiment was conducted to study the effects of four types of tillage and straw management on rice yield and soil properties in central China during 2020–2021. The types of management were no-till with residues retained (NT+S); plow tillage with residue retention (PT+S); no-till with residues removed (NT-S); and plow tillage with residue removed (PT-S). Compared with PT, yield decreased by 38.8% in NT, while straw returning effectively increased the yield of regenerated rice. NT+S increased the yield of main season rice by 37.0% and ratoon rice by 45.3%. Compared with non-returning straw, straw returning increased soil total porosity, soil organic carbon, and activity of β-glucosidase and urease, among which TP and SOC were increased by 8.8% and 27.8%, respectively. The results showed that returning straw to the field could significantly reduce the yield loss caused by no-tillage and improve the soil structure. No-tillage combined with returning straw to the field of regenerative rice is a green, light, and simplified cultivation mode worthy of further exploration. [ABSTRACT FROM AUTHOR]

Land management systems that comprise the principles of conservation agriculture (CA) can lead to soil organic carbon (SOC) gains over time. Nonetheless, how fertilization regimes interfere with their performance in highly weathered soils is still uncertain. This study presents results on SOC storage, crop yield, and soil resilience from a long-term experiment in southern Brazil (Ponta Grossa – Paraná State) 26 years after its establishment in 1989 combining a gradient of soil disturbance through diverse soil management strategies with contrasting fertilization regimes. We hypothesized that preserving soil structure rebuilt over time through no-till system plays a significant role in SOC persistence and the fertilization regime can impact land management performance on soil resilience and crop yield. The experimental design was laid out as a split plot through completely randomized blocks. The main plots comprised the treatments related to soil management systems: 1) conventional plow-based tillage – CT; 2) minimum tillage (Chiselling replacing plowing) – MT; 3) no-till with one chisel plowing every three years – NTch; and 4) continuous no-till system – NTS. The sub-plots comprised full crop fertilization (FCF) for all crops and low crop fertilization (LCF) by suppressing K and P fertilization and maintaining N in broadcast application. SOC stocks significantly improved as the soil disturbance diminished, resulting in higher soil resilience indexes for NTS and NTch. Differences in SOC stocks between the contrasting treatments NTS and CT were higher under low fertilization, resulting in C and N sequestration rates of 1.14 and 0.14 Mg ha−1 year−1 under LCF compared to 0.77 and 0.08 Mg ha−1 yr−1 in FCF at the 0–100 cm layer. Such higher differences were induced by overall higher SOC stocks of CT when under FCF and higher SOC stocks in subsoil depths promoted by NTS when under LCF. High fertilization treatments produced cumulative yields 1.5 times higher for soybeans and 2.5 times higher for corn throughout the 26 years of the experiment. Labile C fractions extracted by hot water (HWEOC) and K-permanganate (POXC) were systematically increased as the disturbance diminished. Gains in labile fractions were promoted in deeper layers in lower disturbance treatments (NTch and NTS). We conclude that combining conservation agriculture principles ultimately defined the potential for SOC sequestration. The high soil resilience under the NTS in this research indicates a considerable potential to reverse the soil degradation and decline of the SOC and labile fractions by conversion to intensive NTS (high and diversified annual C input) associated with absence of soil disturbance. [Display omitted] • The no-till system (NTS) storaged more C under full or low crop fertilization. • The NTS had higher Soil Resilience Index than the other management systems. • The soil labile C was higher in NTS and was the pathways to store more C. • The NTS under low crop fertilization exhibited the greater C sequestration rate. • Soil management that involve greater soil disturbance result in higher carbon loss. [ABSTRACT FROM AUTHOR]

The cultivation of vegetables in general degrades the soil because it is necessary to adopt intensive mechanical preparation operations. The objective of this research was to quantify soil losses (SL) and water losses (WL) by water erosion in the onion cycle in different types of soil and crop residue management, under simulated rainfall conditions, in 2017. No-tillage treatments were studied: 1) furrows in the planting line on the corn residue (NTC); 2) furrows in the planting line over the soybean residue (NTS); 3) soil preparation with a plow + two harrowing + manual rake on the corn residue (SPC); 4) soil preparation with a plow + two harrowing + manual rake on the soybean residue (SPS); 5) soil preparation with one plowing + two harrowing + manual rake without cultivation and uncovered (BS - control). Four simulated rains were applied to the treatments, each lasting 60 min and 65 mm h-1 of constant intensity, with a rain simulator with rotating arms of the thrust type. The total soil losses observed at the end of the four simulated rainfall applied in the treatments NTC, NTS, SPC, and SPS were respectively 1.35; 3.35; 7.36; 33.72; and 55.44 t ha-1. Soil losses verified in the NTC, NTS and SPC treatments were respectively 85%, 63% and 12% lower than the soil loss tolerance of 9 t ha-1 year-1 The increase in soil cover by crop residues caused an exponential decrease in soil losses, while these losses increased exponentially with the increase in runoff velocity. Runoff water losses showed the same trend as soil losses, but with less dependence on soil management. [ABSTRACT FROM AUTHOR]

Intensive agriculture can induce soil degradation through various mechanisms, resulting in a decline in soil health and functionality. Soil arthropods, as an essential component of soil biodiversity, play a pivotal role in numerous ecosystem services for sustainable and productive crop cultivation. This research presents the inaugural nationwide evaluation of agricultural soils in Hungary, using microarthropods as soil quality indicators. Through the examination of 133 soil samples from 78 farms, we explored the direct and indirect effects of soil, plant, climatic variables and farming practices on the biological soil quality of winter wheat fields. Collembola and Acari were the two most common and abundant soil microarthropods. All arthropod-based soil quality and community metrics (QBS-ar, Collembola/Acari, richness, density) exhibited a negative correlation with bulk density, indicating the adverse effects of soil compaction. Notably, soil moisture was found to be a crucial factor that positively influenced the integrated faunal indices, QBS-ar and Collembola/Acari abundance ratio. Collembola proved to be the most responsive taxon, being highly sensitive to variations in both soil moisture and bulk density. In addition, bulk density had a negative effect on the abundance of Pauropoda, Diplura and Formicidae. The frequency of rainy days during the growing season had both direct and indirect positive effects on soil microarthropods, particularly in terms of density. Soil management, specifically ploughing and the number of tillage operations, emerged as primary drivers, indirectly affecting biological soil quality by altering soil structure and moisture conditions. Low-input farming under Hungarian agri-environmental schemes had comparable arthropod-based soil quality indices to conventional wheat fields. In conclusion, our study confirmed that soil microarthropods are suitable for nationwide assessments of agricultural soils and we found that the measures of the Hungarian Agri-Environmental Programme 2004–2009 were insufficient to improve soil biological quality. It is therefore imperative to implement more efficient farming practices that take better account of soil biodiversity and health. • Biological soil quality of winter wheat fields was assessed across Hungary. • Soil compaction and moisture were key factors directly affecting microarthropods. • The most responsive group of soil microarthropods were springtails (Collembola). • Tillage practices indirectly influenced soil microarthropods. • Biological soil quality was comparable in low-input and conventional farming systems. [ABSTRACT FROM AUTHOR]

Copyright of Agronomy Journal / Agronomski Glasnik (0002-1954) is the property of Croatian Society of Agronomists and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Reduced tillage systems have been argued to provide several potential benefits to soil, environment and to farm incomes. In England, while many farms have partially adopted such practices, a large proportion of arable farmers do not undertake reduced tillage in any form. This paper analyses the rationale for and uptake of different cultivation techniques, including analysis of the barriers to adoption of reduced tillage, aiming to benefit policymakers and researchers and increase the spread of smart agricultural practices. Based on a postal questionnaire, we estimated that 47.6% of English arable land is cultivated using minimum‐tillage and 7% under no‐tillage. As farm size increased, so did the probability of reduced tillage uptake. Furthermore, farms growing combinable crops were more likely to utilize reduced tillage approaches than other farm types. Soil type, weed control and weather conditions were noted as the main drivers for 'strategic' and 'rotational' ploughing, constraining continuous reduced tillage use. To effect greater reduced tillage uptake, greater communication between researchers and farmers is needed to facilitate the implementation of sustainable soil management solutions, supported by current legislation permitting responsible herbicide use in arable production. Financial support to access reduced tillage machinery may also be required for farmers operating smaller holdings. Adopting reduced tillage is a continuous learning process requiring ongoing training and information gathering; supporting a network of reduced tillage 'farmer champions' would facilitate practical knowledge exchange, allow farmers to observe soil improvements, understand transition phase barriers and ultimately encourage increased reduced tillage uptake. [ABSTRACT FROM AUTHOR]

Copyright of Ambiência is the property of Revista Ambiencia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The objective of the study was to elucidate the relationship between soil management and carbon (C) stocks, and to identify the factors that intervene in the processes that favor C sequestration. The study was carried out on a farm in the Argentinean semiarid pampas with four land management practices (2019–2021): natural grassland (NG), crop-pasture rotation (RO), soybean monoculture (S-S) and with cover crop (S-CC). Aerial and root biomass were quantified at cover crop termination and soybean flowering. In addition, residues on soil surface were determined two times a year. In all cases, C and N contents were quantified. On composite soil samples, soil organic C (SOC), particulate C (POC), microbial biomass C and N (MBC, MBN), and soluble C and N were determined at 0–0.1 m depth. Results showed that NG had the highest and the most stable aboveground (3807.1 kg residue-C ha-1) and belowground inputs between years (4965.8 kg root-C ha-1). Similar results were observed in RO treatment during the first year (4221.0 kg root-C ha-1) diminishing by 67% after plowing for the annual crop in the second year reaching similar root-C values than S-CC and S-S (721.7 kg ha-1). S-S presented the lowest aboveground (49%) and belowground inputs (77%) compared to NG. Cover crops (S-CC) contributed with 31% and 14% of extra residue-C and root-C, respectively, compared to S-S. MBC showed a non-linear response with increases in root-C, reaching maximum carrying capacity of 110.6 ± 4.3 kg MBC ha-1 with root-C inputs ≥ 2200 kg ha-1. Our results showed significant relationships between root-C and POC and SOC, while no relationships were found for aboveground residues. Increases in soluble N explained 86% of SOC variability. Both RO and S-CC reached the "4 per Mille " goal with an average annual SOC storage rate (ΔC) of 0.24 and 0.16 Mg ha-1 y-1, respectively, while S-S had SOC losses of 0.04 Mg ha-1yr-1. [Display omitted] • NG had higher and stable inputs with 15% more root-C than residue-C. • RO-pasture had similar root-C as NG, diminishing by 67% after plowing. • S-CC contributed with 31% and 14% more residue-C and root-C than S-S. • Root-C and soluble N explained increases in SOC. • Both, RO-pasture and S-CC reached the "4 per Mille " goal. [ABSTRACT FROM AUTHOR]

Ploughing of grassland for reseeding can result in a temporary decline in soil carbon stocks due to reduced gross primary production and increased soil respiration. To improve understanding of processes affecting the decay of soil organic matter after grassland renovation we measured soil respiration and soil carbon stocks for several months after ploughing and reseeding of 16-year-old grass-clover swards on a sandy loam soil in Sep 2010 (I), May 2011 (II), Sep 2011 (III) and May 2012 (IV). Simultaneously, to establish the CO 2 -flux baseline, the ecosystem respiration, consisting of autotrophic and heterotrophic soil respiration, was measured on intact control swards (IG). Collected data were used to calibrate a soil carbon model to estimate mid- and long-term carbon losses. Results showed that, on the basis of the model used, heterotrophic soil respiration from ploughed plots exceeded the IG baseline in all experimental periods (I-IV). The amount of residual plant material at the time of ploughing and increased decay of native soil organic matter for approximately six months after soil disturbance were identified as the main drivers for enhanced soil respiration in the short-term. Long-term simulation of the calibrated model for 100 years indicated that net soil carbon stocks can decrease by 21 and 14 Mg C ha −1 , compared with intact grassland, when sward renovation by reseeding, involving ploughing, is conducted every 5 to 10 years, and that grassland reseeding in spring carries a higher risk of soil carbon losses compared with reseeding later in the year. [ABSTRACT FROM AUTHOR]

Soil tillage and plastic film management practices are essential agricultural production strategies for improving crop yield. Furthermore, they can also play important roles in affecting soil quality, greenhouse gas (GHG) emissions, and carbon footprint (CF), and the overall impacts of tillage and plastic film management on these indicators and the potential links among them are rarely assessed. A 4-year-long field experiment was performed under the winter wheat–summer peanut rotation pattern to investigate how the tillage (plow tillage and rotary tillage) and plastic film management practices (plastic film mulching and no plastic film mulching) affected the summer peanut fields' soil quality (soil carbon (C) stock, enzyme activity, and nutrients concentration), soil GHG (N 2 O and CH 4) emissions, CF components, and peanut yield. The present results showed that plow tillage management improved peanut yield and decreased seasonal cumulative soil N 2 O and CH 4 emissions and CF relative to rotary tillage management. However, the seasonal cumulative emissions of soil N 2 O and CH 4 under plastic film mulching were higher than those under no mulching. The application of plastic film mulching also increased soil TOC stock, soil enzymes (invertase, unease, and catalase) activities, and soil nutrients (microbial biomass C, microbial biomass nitrogen (N), ammonium N, and nitrate N) concentrations. The mulching-induced improvements in soil quality can promote an increase in crop productivity; thus, plastic film mulching showed increased peanut yield and decreased yield-scaled CF. In conclusion, plow tillage combined with plastic film mulching (PTM) treatment maintained higher peanut productivity and produced lower CF while generating suitable soil conditions and therefore may be a more high-yielding, eco-friendly, and sustainable development management strategy for summer peanut production. [Display omitted] • Tillage and plastic film management are crucial strategies for improving crop yield. • Plow tillage improved soil quality and reduced CF. • Plastic film mulching decreased yield-scaled CF. • Plow tillage combined with plastic film mulching produced higher yield and lower CF. [ABSTRACT FROM AUTHOR]

The humidity of the soil and the quality of seedbed preparation is an important factor influencing crop density and early establishment. It largely depends on weather conditions, but partly it can be controlled by soil management system. Field experiments of different soil tillage methods were carried out at Experimental Station of Aleksandras Stulginskis University in 2009. Treatments involved: 1) direct drilling, 2) shallow ploughing (10 cm depth), and 3) deep ploughing (20 cm depth). In the experiment spring barley (Hordeum vulgare L.) variety 'Simba' was cultivated. The soil of experimental site - Calc(ar)i-Endohypogleyic Luvisol (Drainic). The aim of the research was to estimate the influence of soil management system on seedbed parameters and crop density. It was estimated, that the highest roughness of the soil surface (31.8 mm) was, when the soil was ploughed at 20 cm depth, but contrarily the seedbed roughness was the lowest (15.2 mm). Estimated direct drilling depth was 15.6 mm and in ploughed soil it was 51.7-57.4 mm. In ploughed soil at 20 cm depth the seeds were sown too deep - 88.4 % of them were below sowing depth. When direct drilling was used - too shallow - 57.8 % of seeds were above sowing depth. The highest accuracy was estimated in shallow ploughed soil - 43.8 % of the seeds were at sowing depth. Nevertheless in the dry weather conditions spring barley germinated faster when direct drilling was used, later on, experimental results showed, that spring barley crop density was significantly thinner (180 plants per m2) compared to deep or shallow ploughing, whereas depth of the ploughing did not influence thickness of crop stand: it was 431-445 plants per m2. [ABSTRACT FROM AUTHOR]

Tillage methods and crop rotation are probably the two most important cropping factors affecting weed communities, particularly when herbicide use is restricted. This study examined weed dynamics following eleven years of different tillage and crop rotation treatments. The aboveground grass weed flora was recorded each year and the content and vertical location of individual weed seeds within the plough layer (0–20 cm) were determined after 11 years of continuous mouldboard ploughing (P), pre-sowing tine cultivation to 8–10 cm soil depth (H 8-10 ) and direct drilling (D). The content of weed seeds, especially grass weeds, was determined for three distinct soil layers (0–5, 5–10 and 10–20 cm), reflecting the cultivation depths of the tillage treatments. The annual grass weeds, Apera spica-venti and Vulpia myuros , were promoted by non-inversion tillage and in the case of V. myuros also by frequent cropping of winter cereals. The two non-inversion tillage treatments caused a strong stratification of weed seeds within the plough layer, with the majority of the seeds being accumulated in the upper soil layers, at 0–5 and 5–10 cm, and markedly less so in the 10–20 cm layer. Ploughing resulted in a more even distribution between the three layers. It is suggested that in cases where severe grass weed problems have built up in a non-inversion tillage system and where changes in crop rotation are ineffective or undesirable, inversion of the upper soil layer with the lower one could be considered a management option. [ABSTRACT FROM AUTHOR]

The moldboard plow is the most common primary tillage implement in the world; therefore, it is valuable to consider this plow from an engineering viewpoint. Since the required draft force and power are among the most important engineering specifications of a moldboard plow, in this paper, a model was developed to calculate them. In this model, the effect of soil cutting, soil displacement, and soil-metal friction on the plow specific draft was considered. Soil parameters, plow parameters, and working condition parameters were considered as the model inputs. To simplify the required calculations, the derived equations were entered in the Excel software, and the finalized spreadsheet was utilized as the moldboard plow draft force and power calculator. To verify the model, comparison of the model outputs with the corresponding results of other studies was carried out. Furthermore, the output of the model and the measured draft force of plowing on a silty clay loam soil was compared. According to the results of this study, the developed model produced acceptable specific draft forces that were within the overall range of the moldboard plow specific draft. Furthermore, draft force and power requirements of a three-bottom moldboard plow working on a silty clay loam soil with the forward velocity of 7 km h −1 were 17.9 kN, and 34.8 kW, respectively, that were about 8% higher than the results obtained by the developed model (16.64 kN, and 32.28 kW). Therefore, the developed model can be used to calculate the draft force and power of the moldboard plow with reasonable accuracy. [ABSTRACT FROM AUTHOR]

An assessment of soil management impacts on carbon dynamics requires easily applicable tools. The carbon balance model CCB was applied to quantify the impact of different tillage systems on soil organic matter (SOM) dynamics. The model was able to describe the observed dynamics of SOM for conventional tillage (CT), but the correct simulation of ploughless soil management in the minimum tillage (MT) treatment required an adaptation of the calculation of the specific turnover conditions that are quantified as Biologic Active Time (BAT). We hypothesized a texture dependent reduction of the turnover activity with depth and calculated a site specific correction factor for the BAT of minimum-tilled soils where the topsoil is not mixed by ploughing. Without additional calibration we evaluated this approach using the data set of the field experiment in Fuchsenbigl (Austria) that was started in 1989 on a fine-sandy loamy Haplic Chernozem ( FAO, 2006 ). The model predicted a reduced turnover activity with a BAT of 13 d yr −1 for the MT treatment versus 23 d yr −1 for the CT treatment having significant correlations between the modeled pool size of active SOM and the microbiological properties substrate induced respiration and potential nitrogen mineralization. [ABSTRACT FROM AUTHOR]

Nitrite (NO 2 −) oxidation is the second step in nitrification, following ammonia (NH 3) oxidation, and catalyzed by nitrite oxidizing bacteria (NOB). Their activity is critical in preventing toxic accumulation of NO 2 −. The two major NOB genera in soil are Nitrobacter and Nitrospira. This study investigated how N fertilization and tillage management influenced these two NOB communities in long-term (>40 years) maize (Zea mays L.) cropping. To evaluate NOB community changes we used PCR and denaturing gradient gel electrophoresis (DGGE) to analyze Nitrobacter and Nitrospira NO 2 − oxidoreductase genes (nxr). Season, fertilizer rate, and tillage all influenced Nitrobacter and Nitrospira communities, but differentially for the two genera. Nitrobacter was more diverse in summer, whereas Nitrospira was more diverse in winter. Nitrobacter was more diverse in N-fertilized samples, whereas Nitrospira diversity decreased with increasing fertilizer rate in winter but not summer. Nitrobacter diversity was not significantly influenced by tillage, whereas no-tillage samples had more diverse Nitrospira , compared to plow tillage samples. In addition to providing evidence for better understanding the relationship between soil management and NOB communities, this study also helped to suggest linkages between ammonia oxidizing bacteria and Nitrobacter and between ammonia oxidizing archaea and Nitrospira that may facilitate future studies concerning ammonia-oxidizing nitrifiers and NOB. • Season, fertilizer rate, and tillage all influenced Nitrobacter and Nitrospira communities. • Response was differential for the two genera. • Nitrobacter was more diverse in summer; Nitrospira was more diverse in winter. • Nitrobacter diversity increased in N-fertilized samples; whereas Nitrospira diversity decreased. [ABSTRACT FROM AUTHOR]

Soil cultivation is among the principal factors that determine the structure and properties of soil and also affects the species composition and abundance of soil dwelling arthropods. Carabid beetles are a particularly valuable group of arthropods, the species of which are strongly associated with particular soil environments. This paper discusses the effect of soil tillage on carabid beetle assemblages. The study was carried out near Olsztyn, in northeastern Poland. Six wheat fields, each cultivated using either, conventional or non-inversion, soil tillage, were chosen. Carabid beetles were caught in Barber's traps from early April to the end of October 2011. In total, 7,486 specimens belonging to 55 species of the family Carabidae were captured. The most numerous were Poecilus cupreus, Pterostichus melanarius, Harpalus rufipes, Anchomenus dorsalis and Carabus granulatus. Differences in the abundance of ground beetles and some life history traits were associated with the two soil tillage systems. In particular, ploughing reduced carabid abundance and resulted in the increased activity of medium-sized zoophages and spring breeders. [ABSTRACT FROM AUTHOR]

A field study was carried out to evaluate the effects of tillage practices on soil physical properties in Mwala district, Eastern Kenya, duringthe long rains (LR) and short rains (SR) of 2012/13. The treatments were disc ploughing (DP), disc ploughing and harrowing (DPH), ox-ploughing (OX), subsoiling-ripping (SSR), hand hoeing with tied ridges (HTR), hand hoeing only (H). These were investigated under three cropping systems of sole maize, sole bean, and maize-bean intercrop in a split-plot design with four replications. Soil physical properties were monitored at different weeks after planting (WAP) throughout the growing seasons. A four-season average shows that soil moisture content was significantly (P < 0.05) higher in OX > SSR > DPH > H > HTR > DP with values ranging from 13.1 to 14.1%. Soil surface roughness and crust strength varied significantly (P < 0.05) over time within the growing seasons, between the tillage practices, and across the different seasons with values ranging from 26 to 66% and 1.21 to 1.31 MPa, respectively. Tillage practices and cropping systems did not significantly affect bulk density, porosity, or Ksat values. It is apparent that long term tillage experiment (>4 seasons) would be required to detect changes in soil physical properties as a result of the soil management practices. [ABSTRACT FROM AUTHOR]

Field experiments (2009-2010) were carried out in soybean on lessive pseudogley soil in north-eastern Croatia to evaluate the impact of three continuous tillage systems (conventional with mouldboard ploughing, chisel ploughing, disk harrowing) and chemical weed control through split application of post-emergence herbicides at reduced rates alone or in combinations, on weed density, fresh weed biomass and crop yield. Total weed density in untreated plots was significantly influenced by tillage and it was the highest in disk-harrowing (202.0 plants m"2), medium in chisel ploughing (126.5 plants m"2) and the lowest in mouldboard ploughing (109.3 plants m"2). In comparison with conventional tillage, chisel ploughing and disk harrowing increased weed number on average by 15% and 85%, respectively, after only two years of experiment. The main weeds were annual species of Echinochloa crus-galli (L.) PB., Ambrosia artemisiifolia L., Chenopodium album L., and Polygonum lapathifolium L. with a share of 89% and 83% of the total weed population and biomass, respectively. The efficacy of herbicide treatments in the control of main weeds did not vary significantly between tillage treatments. The best and equal total weed biomass reduction of 96% was provided by both herbicide combinations of imazamox 24 g + oxasulfuron 50 g plus thifensulfuronmethyl 6 g a. i. ha"1 and of oxasulfuron 60 g + oxasulfuron 60 g plus thifensulfuron-methyl 4 g a. i. ha"1, whereas the treatment with imazamox 24 g + 24 g a. i. ha"1 reduced the weed biomass by 93%. Weed control had no impact on soybean yields that were significantly affected by year and tillage. Compared to the highest yield with mouldboard ploughing (4183 kg ha"1), the average percent yield decreases with chisel ploughing and disk harrowing were 6% and 14%, respectively. [ABSTRACT FROM AUTHOR]

The article presents a study regarding the impact of physical structure on fungal growth dynamics by combining a physiologically based model of fungal growth with digitized images of internal pore volume of samples of undisturbed soil with different management practices. It is investigated by measuring the pore geometries of the soil samples in chisel plow (CT) and no till (NT). Results of the study indicate the disadvantaged fungal invasion of the fragmented pore space in soils under NT.

Abstract: Clean cultivation is a common practice in rainfed orchards; however, it may have detrimental effects on soil properties. This study examines the effect of different soil management systems on physical, chemical, and biochemical properties in a hypercalcic Calcisol in rainfed almond orchards (Prunus dulcis (Mill.) D.A. Webb) in SE Spain. Four types of soil management (main-plot treatments) were compared to a frequently tilled orchard system (FT: three or four tillages per year). The four types of soil management were: fencing (SF) of a flock of 130 sheep in 0.4ha and grass cover was kept throughout the growing season; native vegetation (NV) that was allowed to grow; cover crop (CC) composed of legumes and crucifers; and reduced tillage (RT) comprising autumn and spring chisel ploughing. Each type of soil management was split into two grazing treatments (subplot treatments): with and without grazing. Our results supported the hypothesis that clean cultivation, i.e., FT, has deleterious effects on soil properties compared with managed groundcover. Compared with FT treatment, at the end of the experiment, the rest of treatments had higher wet aggregate stability (except the SF treatment), soil organic carbon (10.6gkg−1 vs. 5.4gkg−1, mean groundcover treatments vs. FT), total nitrogen (1.35gkg−1 vs. 0.83gkg−1, mean groundcover treatments vs. FT), available potassium (332mgkg−1 vs. 187mgkg−1, mean groundcover treatments vs. FT), and dehydrogenase (2.6μgINTFg−1 h−1 vs. 1.9μgINTFg−1 h−1, mean groundcover treatments vs. FT), arylsulphatase (12.8μgPNPg−1 h−1 vs. 6.5μgPNPg−1 h−1, mean groundcover treatments vs. FT), β-glucosidase (569μgPNPg−1 h−1 vs. 300μgPNPg−1 h−1, mean groundcover treatments vs. FT), and phosphatase activity (394μgPNPg−1 h−1 vs. 220μgPNPg−1 h−1, mean groundcover treatments vs. FT). Grazed plots had higher water content in soil (10gH2Okgsoil−1 vs. 9.4gH2Okgsoil−1, grazed vs. not grazed plots) and greater levels of arylsulphatase (12μgPNPg−1 h−1 vs. 11μgPNPg−1 h−1, grazed vs. not grazed plots), β-glucosidase (582μgPNPg−1 h−1 vs. 491μgPNPg−1 h−1, grazed vs. not grazed plots), and phosphatase activity (396μgPNPg−1 h−1 vs. 345μgPNPg−1 h−1, grazed vs. not grazed plots), in late spring, and this is attributed to the reduction of evapotranspiration and to the stimulation of root activity by means of plant defoliation. In conclusion, under the conditions of this study, managements including grass cover improved physical, chemical and biological properties of soil compared with frequent tillage, particularly when grass was early removed by grazing. [Copyright &y& Elsevier]

Abstract: For thousands of years, smallholder-based crop farming in Ethiopia has been practiced with oxen ploughing using the traditional Maresha ard plough where consecutive tillage operations are undertaken perpendicular to each other. Despite its wide acceptance by smallholder farmers, long-term use of the Maresha is believed to deteriorate the soil''s physical properties. This study examines the surface and subsurface infiltration, soil evaporation and penetration resistance of sandy loam soils that have been exposed to varying durations (0, 2, 7, 22 and 35 years) of cultivation after being converted from acacia-based grassland dominated by Acacia tortilis and Acacia senegal in the Central Rift Valley (CRV) of Ethiopia. The infiltration rate of the surface layer increased significantly (p =0.05) immediately after conversion from acacia-based grassland to cultivated land. Thereafter, there was a weak decreasing trend (p >0.05, R 2 =0.24) in infiltration rate with years of cultivation. Unlike the surface soil layer, there was no significant difference in the subsurface (below 15cm) infiltration between the acacia-based grassland and lands cultivated for varying numbers of years. Following a rain event satisfying field capacity of the soils, the daily soil evaporation increased significantly (p =0.05) with increased duration of cultivation. The cumulative evaporation, observed over 5 consecutive days following the last rainfall, increased by 2.4 times in the 35 years old cultivated land from the acacia-based grassland. There was also a strong correlation (R 2 =0.86) between α (the slope of the cumulative evaporation versus the square root of time) and an increase in the years of cultivation. It is, therefore, concluded that long-term Maresha cultivation along with the present soil management makes the maize crop susceptible to drought and dry-spells. Improved soil management and development of appropriate tillage are needed to maximize rainwater use efficiency and achieve a more sustained agricultural production in the drought-prone CRV of Ethiopia. [Copyright &y& Elsevier]

Ploughing is a draught intensive operation that becomes a limitation for small tillage machines like the power tiller due to lower availability of draught. Ploughing is possible using power tiller with the adoption of an implement that requires less draught like oscillatory tillage tool. In order to enable dry land tillage from a small machine, a novel power tiller-operated oscillatory tillage implement was designed and developed. The work included modification of transmission system of power tiller to provide required frequency (9–13Hz), designing a new rotary shaft to impart oscillation and give required amplitude (15–35mm). Prototype oscillatory tillage implement thus developed was tested in terraced land field conditions and compared with the same working in non-oscillatory mode of operation. Prototype oscillatory tillage implement having 25cm tool width operated up to 15.3cm depth in dry, untilled field conditions. However, the same implement operated only up to 7.4cm depth in non-oscillatory mode of operation. The volume of soil handled per unit time, fuel consumption and tillage performance index were higher (94.88m3 h−1, 2.70lh−1 and 2.99, respectively) with prototype oscillatory tillage implement working at average 15.3cm depth of operation as compared to the same implement working in non-oscillatory mode of operation. [Copyright &y& Elsevier]

The environmental consequences of changing from conventional to reduced soil tillage in winter crops are yet poorly understood under North European conditions. Soil tillage intensity may affect both crop growth and soil carbon (C) and nitrogen (N) turnover and balances, including emissions of greenhouse gases (GHG) such as CO2 and N2O. In this study we compared the effects of conventional tillage (CT) using mouldboard ploughing to 20cm depth, reduced tillage (RT) using rotary harrowing to 8–10cm depth and direct drilling (DD) with disk coulters on fluxes of CO2 and N2O from loamy sand soil under winter oilseed rape (Brassica napus L.) followed by winter wheat (Triticum aestivum L.). The measurements were conducted by use of chambers over a period from August 2003 to July 2005 in a soil tillage experiment established in Denmark in 2002. To integrate information on the C and GHG budgets for the experiment, the FASSET model was used with no recalibration in a two-step modelling procedure. First, we fitted the soil organic matter (SOM) model of FASSET to give the observed ratio of soil CO2 respiration from the CT and DD treatments by scaling all decomposition and maintenance parameters for the DD treatment with the same value (δ), called the “tillage factor”. Second, the complete FASSET model was run with default parameter value for ploughing depth in CT (δ =1.00) and the estimated value for DD (δ =0.57), in order to quantify the cumulated CO2 and N2O emissions. Both measurements and model simulations showed that the combined global warming potential (GWP) from CO2 and N2O emissions was lower from reduced tillage treatments (RT and DD) than from conventional tillage. Thus, compared with CT, modelled reduced soil tillage treatments decreased GHG emissions by 0.56 (RT) and 1.84 (DD)MgCO2-eq.ha−1 year−1. Similar differences between treatments were obtained for simulations over 30 years of observed weather for the specific site. In both cases, negative GWPs for the studied site were obtained. A sensitivity analysis showed that the simulated GHG emissions were primarily influenced by changes in SOM model parameters, whereas observed changes in soil water retention affected only N2O emissions, and soil temperature had only minor effects. [Copyright &y& Elsevier]

While the adoption of no-till (NT) usually leads to the accumulation of soil organic C (SOC) in the surface soil layers, a number of studies have shown that this effect is sometimes partly or completely offset by greater Soc content near the bottom of the plow layer under full-inversion tillage (FIT). Our purpose was to review the literature in which soc profiles have been measured under paired NT and FIT situations. Only replicated and randomized studies directly comparing NT and FIT for >5 yr were considered. Profiles of soc had to be measured to at least 30 cm. As expected, in most studies soc content was significantly greater (P < 0.05) under NT than FIT in the surface soil layers. At the 21- to 25-cm soil depth, however, which corresponds to the mean plowing depth for the data set (23 cm), the average soc content was significantly greater under FIT than NT Moreover, under FIT, greater soc content was observed just below the average depth of plowing (26-35 cm). On average, there was 4.9 Mg ha-1 more soc under NT than FIT (P = 0.03). Overall, this difference in favor of NT increased significantly but wealdy with the duration of the experiment (R2 = 0.15, P = 0.05). The relative accumulation of soc at depth under FIT could not be related to soil or climatic variables. Furthermore, the organic matter accumulating at depth under FIT appeared to be present in relatively stable form, but this hypothesis and the mechanisms involved require further investigation. [ABSTRACT FROM AUTHOR]

Ground beetles are well known as beneficial organisms in agroecosystems, contributing to the predation of a wide range of animal pests and weed seeds. Tillage has generally been shown to have a negative effect on ground beetles, but it is not known whether this is because of direct mortality or the result of indirect losses resulting from dispersal caused by habitat deterioration. In 2005, field experiments measured direct, tillage-induced mortality, of four carabid weed seed predators, Harpalus vufipes DeGeer, Agonum muelleri Herbst, Anisodactylus merula Germar, and Amara cupreolata Putzeys, and one arthropod predator, Pterostichus melanarius Illiger, common to agroecosystems in the northeastern United States. Three tillage treatments (moldboard plow, chisel plow, and rotary tillage) were compared with undisturbed controls at two sites (Stillwater and Presque Isle) and at two dates (July and August) in Maine. Carabid activity density after disturbance was measured using fenced pitfall traps installed immediately after tillage to remove any effects of dispersal. Rotary tillage and moldboard plowing reduced weed seed predator activity density 52 and 54%, respectively. Carabid activity density after chisel plowing was similar to the undisturbed control. This trend was true for each of the weed seed predator species studied. However, activity density of the arthropod predator P. melanarius was reduced by all tillage types, indicating a greater sensitivity to tillage than the four weed seed predator species. These results confirm the need to consider both direct and indirect effects of management in studies of invertebrate seed predators. [ABSTRACT FROM AUTHOR]

The period after ploughing of grass–clover leys within a ley-arable rotation is when nitrogen accumulated during the ley phase is most vulnerable to loss. We investigated how ploughing date and timing of cessation of grazing before ploughing affected nitrous oxide (N2O) losses of the first cereal crop. Ploughing dates were July and October for a winter wheat pilot study and January and March for spring barley in the main experiment. Timings of cessation of grazing (main experiment only) were October, January and March. Spring barley yield, nitrogen uptake and soil mineral nitrogen were also assessed. A separate large-scale laboratory incubation was made to assess the effect of temperature and rainfall on nitrous oxide emissions and nitrate leaching under controlled conditions. Nitrous oxide emissions in the 1- to 2-month period after autumn or spring ploughing, or sowing were typically between 20 and 150 g N ha−1 day−1 and increased with temperature and rainfall. Tillage for crop establishment stimulated N2O emissions with up to 2.1 kg N ha−1 released in the month after spring tillage. Cumulative nitrous oxide emissions were greatest (∼8 kg ha−1 over 17 months) after cessation of grazing in March before March ploughing, and lowest (∼5.5 kg ha−1) after cessation of grazing in January before January ploughing. These losses were 1.2–3.9% of the N inputs. In the laboratory study, winter ploughing stimulated nitrate leaching more than nitrous oxide emissions. The optimum time of ploughing appears to be early spring when the cold restricts nitrogen mineralization initially, but sufficient nitrogen becomes available for early crop growth and satisfactory N offtake as temperature increases. Early cessation of grazing is advantageous in leaving an adequate supply of residues of good quality (narrow C:N ratio) for ploughing-in. Restricting tillage operations to cool, dry conditions, being aware of possible compaction and increasing the use of undersown grass–clover should improve the sustainability of organic farming. [ABSTRACT FROM AUTHOR]

One of the main effects of soil tillage is that it determines the distribution of crop residues in the soil profile. Little information is available on how this affects the distribution of carbon (C) and nitrogen (N) in the soil and more specifically in soil aggregates, as in general the contribution of other effects of tillage (i.e. mechanical disturbance) cannot be distinguished. A laboratory experiment was conducted with repacked soil columns to improve our understanding of the mechanisms of soil aggregate stabilization and storage of organic C in relation to residue location. Double-labelled oilseed rape residues (13C and 15N) were incorporated in the 0–10 cm soil layer or left on the soil surface. The soil columns were incubated for 33 weeks at 20°C. Artificial rain events followed by evaporation imposed several dry-wet cycles on the soil-residue system. Spatial separation of surface-placed residues from the soil slowed down the decomposition rate compared with incorporated residues. This resulted, in the short term, in a large fraction of residue fragments at the soil surface (equivalent to 52% of carbon applied). In contrast, initial crop residue location did not significantly affect incorporation of residue-C in soil aggregates (only 10–12% of carbon applied), as new C entered the aggregate fractions mainly as soluble C. However, concentrations of residue-derived C and N were greater and aggregation increased near the soil surface with mulch, which in the longer term can modify physical and biological properties of the upper cm of the soil. [ABSTRACT FROM AUTHOR]

Abstract: Micropores are important to soil moisture retention and plant growth. Microporosity and pore size distribution were evaluated using mercury intrusion porosimetery on aggregates from 35-year-old experiments started in 1962 at Wooster (40.5°N, 82°W) and South Charleston (39.8°N, 84°W) in Ohio, USA and from three land use practices on Kolombangara (8°S, 157°E) in Solomon Islands. Tillage treatments in Ohio included: moldboard plowing (MP), chisel plowing (CP), and no-till (NT) with continuous corn. The land use treatments in Kolombangara included: natural forest (NF), traditional farming (TF) and topsoil removal (TR). Pore size measured in aggregates ranged from 0.2 to 100μm in diameter. Median pore radius was significantly (P <0.05) larger for NT than for MP and CP treatments at Wooster, but not at South Charleston. Tillage treatments had significant effect on the volume of both storage and residual pores for both sites in Ohio. Volume of storage and residual pores were higher for Wooster than South Charleston soil. At Kolombangara, the NF treatment had significantly larger median and peak pore radii, and microporosity than TF and TR treatments. There was, however, no significant difference among treatments in the volume of pore size distribution. These data support a recommendation for adoption of no-till or conservation tillage in soils of the temperate region, and of minimal disturbance and effective erosion control in soils of the tropics. [Copyright &y& Elsevier]

Abstract: Restricting tillage to shallow-mixing operations as conducted in many conservation tillage systems occasionally causes problems such as compaction of the formerly ploughed layer or severe weed and slug infestation. To overcome these constraints, one moulboard ploughing operation is carried out and, subsequently, cultivation is shifted back to non-inverting shallow-mixing tillage. This study investigated the effect of one single ploughing action conducted after several years of conservation tillage on the amount of organic matter in the soil profile. It was hypothesized that soil organic carbon (SOC) and soil nitrogen (SN) stocks decrease very rapidly during the first few months after ploughing. The study was carried out in temperate climate on three adjacent fields with loess-derived soil (Stagnic Luvisol) located in southern Lower Saxony, Germany. The crop rotation included sugar beet (Beta vulgaris L.), winter wheat (Triticum aestivum L.), winter barley (Hordeum vulgare L.), and white mustard (Sinapis alba L.) as a catch crop. Conservation tillage started in 1992 on all fields and consisted of 30cm deep non-inverting tillage combined with shallow-mixing (10cm deep) operations. Mouldboard ploughing (30cm deep) was conducted once in each field in August 1998–2000 prior to sowing of mustard. Thereafter, shallow conservation tillage (10cm) was established. Soil samples were taken once before and at three dates (1–6 months, 7–9 months, 1.5–2.5 years) after ploughing and masses of SOC and SN were determined. After 7–9 years of conservation tillage, SOC and SN were concentrated in the top 10cm layer of the soil. One ploughing operation resulted in a substantial loss of organic matter. At 0–30cm soil depth, losses of 0.26kgm−2 SOC and 0.046kgm−2 SN occurred within 1–6 months after ploughing, accounting for 4 and 7% of the total initial masses, respectively. At the soil layer of 0–45cm, these early losses were much lower (2% and 5% of the initial masses of SOC and SN per unit of soil area, respectively), caused by an increase of masses in the 30–45cm depth. Further losses of SOC and SN from the 0–30cm layer were small, while from the lower layer a second pronounced loss of organic matter occurred. After 1.5–2.5 years after ploughing, losses from the 0–45cm depth accounted for 6% and 10% of the initial total mass of SOC and SN, respectively. In temperate climate, one ploughing operation after several years of conservation tillage obviously causes a partial loss of organic matter within a few weeks after ploughing. [Copyright &y& Elsevier]

The study aimed to determine the number of cultivation cycles required to reform the plough sole once it has been destroyed or removed from the paddy. An ad hoc infiltration column experiment, which is a cylinder of 50 cm in diameter and 140 cm long, was setup to simulate the processes of ploughing and compaction, the two major forces exerted by a tractor, for developing a plough sole in rice paddy. Three experimental conditions were investigated, namely developing the plough sole by ploughing, compaction, and a combination of ploughing and compaction. The results of the change in the infiltration rate, soil dry bulk density, and weight percentage of clay in an experimental soil column were measured and evaluated. The experimental results show that, the infiltration rate decreases to 63, 29, and 2% of its initial value with ploughing eight times, compaction 30 times, and combination of ploughing and compaction 14 times, respectively. Moreover, the soil bulk density increases from 1.51 to 1.53, 1.61, and 1.71 g cm-3, respectively. Finally, the weight percentage of clay in the plough sole as a result of clay particles moving down from above and increases from 6.2 to 8.2, 6.2, and 14.8%, respectively, over the experimental period. The ploughing rearranged clay content distribution and the compaction increased soil bulk density. Applying these two practices in sequence effectively increased the soil bulk density and reduced the infiltration rate. The results also indicate that after 14 ploughing and compaction the infiltration rate did not further decrease, suggesting that the soil structure could no longer be changed and the plough sole had successfully been reformed. The quantitative result of this work provides valuable information on how to rehabilitate a plough sole once it has been destroyed and needs to be reformed from the paddy field. [ABSTRACT FROM AUTHOR]

The influence of several long-term conventional and conservation tillage treatments on the incidence and the diversity ofFusariumspp. in soil was studied. Soil samples were randomly collected from naturally contaminated field trials and Fusarium species were isolated by using the dilution plate method. The identification of the species was done by direct microscopic observation onFusarium-specific media. The isolation frequency ofFusariumspecies and the total number of colony forming units was affected by the sampling year and the cultivated crop and showed significant differences between the tillage treatments. Moldboard plough-treatments resulted in a lower diversity of Fusarium species than the chisel plough and rotary tiller treatments. Besides the tillage system the tillage depth also appeared to affect theFusariumpopulations. The deeper the tillage the lower was the number of isolatedFusariumspp. TwentyFusariumspecies were identified over both years of investigation. In conservation tillage plots a higher diversity ofFusariumspecies was found than in the moldboard plough-based tillage plots. A correlation betweenFusariumspecies producing the mycotoxin deoxynivalenol (DON) isolated from soil and the DON-content of grain could not be observed. However, these investigations indicate that conservation soil tillage results in conditions which increase the incidence ofFusariumspecies in soil. [ABSTRACT FROM AUTHOR]

By this in vitro study addressing greenhouse gas (GHG) emissions from soil-plant mesocosms, we suggest a method to investigate the joint effects of environmental conditions, growth of plants, and agricultural soil management. Soils from two long-term agricultural trials in France were placed in climate chambers. The rotation trial was with or without grain legumes, and the tillage trial used plowing or reduced tillage. Environmental conditions consisted of two contrasting temperature regimes combined with ambient (400 ppm) or high (700 ppm) CO2 concentrations in climate chambers. The plant growth went from seeding to vegetative growth. Carbon dioxide gas exchange measurements were conducted in both soil types for a period representing initial plant growth. The CO2 exchange was influenced by the growing plants increasing the mesocosm respiration and gross ecosystem production. The environmental settings had no noticeable impact on the CO2 exchange in the soils from the legume trial. The CO2 exchange from the tillage trial soils exhibited variations induced by the environmental conditions depending on the tillage treatment. The N2O emission measurements in the legume trial soils showed little variability based on rotation, however, in soils with legumes, indications that higher temperatures will lead to more N2O emission were seen. [ABSTRACT FROM AUTHOR]

• Reduced tillage using a rototiller is recommended for organic zucchini cultivation. • Ploughing is not a preferred tillage method after cover-crop cultivation. • Rotary tillage, especially with fresh biomass mulch, has a positive effect on soil microbial community. In organic farming, reduced tillage aims to maintain the natural fertility of the soil, including its microbiological diversity. Cultivation practices that change the properties of the soil environment determine conditions of plant growth and yield as well as the chemical composition of the biomass. The methods and dates of performing soil cultivation treatments in organic vegetable production were studied in southern Poland, in the years 2016–2018. The following cultivation combinations were applied: conventional autumn ploughing tillage (APT), spring ploughing tillage (SPT), spring rotary tillage (SRT), spring rotary tillage with polypropylene nonwoven (surface mass of 50 g m−2) mulch (SRTPM), and spring rotary tillage with fresh biomass mulch (SRTBM). The experiment was established on a site where a mixture of white clover (Trifolium repens L. cv. 'RD 84') and Italian ryegrass (Lolium multiflorum Lam. cv. 'Gaza') was grown for green manure, which constituted a forecrop for zucchini (Cucurbita pepo L.) cv. 'Partenon' F1. The fresh biomass of clover and grass was used to mulch the soil on the SRTBM plots. It was shown that the spring soil cultivation with a rotary tiller before planting zucchini plants resulted in a higher marketable yield of zucchini fruit compared to the ploughing performed in the spring (an increase by 34.3%) and the ploughing performed in the autumn (an increase by 25.3%), but these differences are not statistically confirmed. The date of ploughing did not significantly affect the extent of weed infestation on the experimental plots. Zucchini fruit harvested in the last year of study (2018) were characterized by the strongest antioxidant activity and contained the highest amount of total phenols. The study demonstrated a beneficial effect of the reduced tillage and mulching with fresh biomass (SRTBM) on bacterial population (1.56 × 109 CFU g−1 DW) in the soil. [ABSTRACT FROM AUTHOR]

• Tillage rather than N fertilizer played the dominant role affecting the AOA community. • Fertilizer rate did not significantly influence AOA diversity. • In winter AOA were more diverse in NT than PT. • Unique groups occurred in different treatments. Ammonia-oxidizing archaea (AOA) catalyze a rate-limiting step in nitrification - ammonia (NH 3) oxidation. There are more AOA than ammonia-oxidizing bacteria (AOB) in many soil systems, including cropland, and AOA dominate in unfavorable environmental conditions, such as soils with low NH 4 -N. The ecological role of the ubiquitously distributed AOA is unclear, as are the factors regulating AOA community dynamics. This study investigated how long-term N fertilization and tillage management influenced the AOA community in cropland. The study site was a long-term (>40 years) field experiment with either no-tillage (NT) or plow tillage (PT) at three N fertilizer rates (0, 168, and 336 kg ha−1) and continuous maize (Zea mays L.). We used PCR-denaturing gradient gel electrophoresis (DGGE) to assess the archaeal amoA gene as a measure of the changing AOA community. Tillage rather than N fertilizer played the dominant role affecting the AOA community. Fertilizer rate did not significantly influence AOA diversity, but sample season and N fertilization had selection function on AOA composition. In winter, AOA were more diverse in NT than PT. Unique groups were discovered in different treatments, demonstrating selection by tillage, fertilization, season, and/or their interactions. The significant tillage regulation of AOA provides new clues to investigate which environmental factors influence the AOA community and to explore its ecological significance in agricultural land. [ABSTRACT FROM AUTHOR]

To follow the hypothesis that agricultural management practices affect structure and function of the soil microbiome regarding soil health and plant-beneficial traits, high-throughput (HT) metagenome analyses were performed on Chernozem soil samples from a long-term field experiment designated LTE-1 carried out at Bernburg-Strenzfeld (Saxony-Anhalt, Germany). Metagenomic DNA was extracted from soil samples representing the following treatments: (i) plough tillage with standard nitrogen fertilization and use of fungicides and growth regulators, (ii) plough tillage with reduced nitrogen fertilization (50%), (iii) cultivator tillage with standard nitrogen fertilization and use of fungicides and growth regulators, and (iv) cultivator tillage with reduced nitrogen fertilization (50%). Bulk soil (BS), as well as root-affected soil (RS), were considered for all treatments in replicates. HT-sequencing of metagenomic DNA yielded approx. 100 Giga bases (Gb) of sequence information. Taxonomic profiling of soil communities revealed the presence of 70 phyla, whereby Proteobacteria, Actinobacteria, Bacteroidetes, Planctomycetes, Acidobacteria, Thaumarchaeota, Firmicutes, Verrucomicrobia and Chloroflexi feature abundances of more than 1%. Functional microbiome profiling uncovered, i.a., numerous potential plant-beneficial, plant-growth-promoting and biocontrol traits predicted to be involved in nutrient provision, phytohormone synthesis, antagonism against pathogens and signal molecule synthesis relevant in microbe–plant interaction. Neither taxonomic nor functional microbiome profiling based on single-read analyses revealed pronounced differences regarding the farming practices applied. Soil metagenome sequences were assembled and taxonomically binned. The ten most reliable and abundant Metagenomically Assembled Genomes (MAGs) were taxonomically classified and metabolically reconstructed. Importance of the phylum Thaumarchaeota for the analyzed microbiome is corroborated by the fact that the four corresponding MAGs were predicted to oxidize ammonia (nitrification), thus contributing to the cycling of nitrogen, and in addition are most probably able to fix carbon dioxide. Moreover, Thaumarchaeota and several bacterial MAGs also possess genes with predicted functions in plant–growth–promotion. Abundances of certain MAGs (species resolution level) responded to the tillage practice, whereas the factors compartment (BS vs. RS) and nitrogen fertilization only marginally shaped MAG abundance profiles. Hence, soil management regimes promoting plant-beneficial microbiome members are very likely advantageous for the respective agrosystem, its health and carbon sequestration and accordingly may enhance plant productivity. Since Chernozem soils are highly fertile, corresponding microbiome data represent a valuable reference resource for agronomy in general. [ABSTRACT FROM AUTHOR]

Double tines subsoiler was used to study the effect of the tractor forward speed and plowing depth on its draft force and specific resistance using three plowing depths 25,35 and 45 cm and three forward speed 0.27 ,0.31 and 0.52 m /sec in plowed and unplowed silty clay soils . The results indicated that there is a significantly increase in draft force with the tractor forward speed 44 % ,41% and 40% for plowing depth 25,35 and 45 cm when the forward speed increased from 0.27 m/sec to 0.52 m/sec , respectively. The draft force also increased as plowing depth increase for all the forward speeds ,the unplowed soil draft force required was greater than plowed soil .The result also showed a significant increasing in the specific resistance as the forward speed increased , the forward speed 0.52 m/sec gave the highest specific resistance for all plowing depths .however , the specific resistance decreased as the plowing depths all forward speeds , the reduction in specific resistance was 35 % and 33 % when plowing depth increased from 25 cm to 45 cm in plowed and unplowed soils , respectively . [ABSTRACT FROM AUTHOR]