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Tubers and root crops are a typical element of the crop rotation system widely practiced in the Swiss Plateau and especially prone to soil erosion by water, resulting in recurrent soil loss and considerable off-site damage. Improved cultivation practices are therefore needed to counteract and mitigate the erosion risk. This research evaluates the effectiveness of a device called the “Dyker”, which was trialled during two cropping seasons. The Dyker consists of a set of parallel wheels with three inclined shovels each. It is attached to the rear end of a potato planting machine and digs holes into the bottom of the furrows between the potato ridges. The holes are intended to improve water infiltration, and minimize surface runoff and soil erosion. A dye tracer experiment showed that in treated furrows, water infiltrates the compacted subsoil below the plough horizon, while in untreated furrows, hardly any water infiltrates deeper than 20 cm below the surface. Drone photographs showed that the Dyker effectively reduces the amount of stagnant water in depressions: while in treated furrows, rainwater was evenly retained in small holes and infiltrated the soil locally, in untreated furrows it drained to the lowest point of the plot. Due to saturation, excess water remained in the untreated furrows for several days and created anaerobic conditions in the adjacent potato ridges and ultimately led to crop failure. In addition, measurements of temporal and spatial changes of the cross-sectional geometry of furrows showed more erosion and deposition processes in untreated furrows. The positive changes in surface structure diminish in time, as the small holes between the micro-dams gradually fill up, depending on rainfall amounts and intensities.

Farmers' use of tillage implements under extremely dry soil conditions, ignoring optimum soil moisture conditions, results in low field efficiency, high fuel consumption and ultimately poor soil structure. Accordingly, the effect of tillage, applied under a range of near-plastic-limit soil moisture contents, on the efficiency of conventional tillage implements and subsequent soil structure, was investigated. Two conventional tillage systems: (i) moldboard plough followed by two cultivator passes and (ii) disk plough followed by two cultivator passes, were factorially combined with four soil moisture contents ( θ ) at tillage: dry soil, θ = 5.0% w/w, and at 70, 80 and 90% of the moisture content at the soil's plastic limit (0.7 θ pl , 0.8 θ pl and 0.9 θ pl , respectively). The lowest field efficiency was observed under dry conditions, with a significant increase in efficiency at 0.7 θ pl , a further increase at 0.8 θ pl , and a subsequent decrease, compared to 0.7 θ pl and 0.8 θ pl , at 0.9 θ pl . Similarly, fuel consumption was greatest under dry conditions, decreasing at 0.7 θ pl and 0.8 θ pl , only to increase again at 0.9 θ pl . Overall, the lowest fuel consumption occurred at 0.8 θ pl . Under dry soil conditions the proportion of large aggregates (> 8 mm) was the lowest and that of small aggregates ( θ pl the converse was the case. At 0.7 θ pl and 0.8 θ pl , the proportions of large and small aggregates were low, while the proportion of desirable aggregates was greatest. At 0.8 θ pl the proportion of medium aggregates was greater than that at 0.7 θ pl . Therefore, in terms of post-tillage soil structure 0.8 θ pl was deemed the optimum θ for tillage of a silty loam soil. The aggregate stability of soil was higher under dry conditions and 0.7 θ pl , and lower at 0.8 θ pl and 0.9 θ pl under both moldboard and disk ploughing. A somewhat similar trend was observed under both conventional tillage implements; however, the disk plough followed by two cultivator passes offered a better performance in terms of field efficiency and soil properties than did the moldboard plough followed by two cultivator passes.

Conservation tillage, that is, reduced or zero tillage, can change the soil ecological environment and rhizosphere bacterial communities. Here, we investigated temporal variations in rhizosphere bacterial communities during crop development and their relationships with crop growth characteristics under three tillage practices (Plow tillage (PT), chisel plough tillage (CPT), and zero tillage (ZT)) in maize and soybean fields on the Loess Plateau of China. Conservation tillage (CPT and ZT) practices significantly increased the contents of soil moisture (3.62–13.13%), soil organic carbon (29.19–39.67%), and nitrogen (38.69–60.23%) and decreased soil pH (1.15–3.76%). The overall responses of rhizosphere bacterial community composition to tillage practice and phenological period were taxonomically consistent across maize and soybean fields, and changes were predominantly observed in the relative abundances of dominant bacterial phyla. Co-occurrence network analysis indicated that the average connectivity degree among 16S operational taxonomic units was higher under PT (38.92% and 73.60%) practice than under CPT and ZT practices. CPT practice tended to increase the total biomass and nitrogen accumulation of maize and soybean compared with PT practice, whereas ZT practice significantly (P

Land management history can influence soil organic carbon (SOC) stocks over centuries. In this study, the impact of medieval ridge and furrow cropland management on SOC in forests was assessed. Continuous clockwise ploughing in rectangular fields moved topsoil from the outer part of strip-shaped fields towards the centre, thus forming a corrugated microtopography with peripheral furrows and central ridges. This tillage technique led to the burial of former topsoil under the ridges. The effect of this human-created microtopography and the centuries old topsoil burial on forest SOC spatial distribution and stocks was investigated. Five sites with ridge and furrow field strips under deciduous forests on soils of differing texture in Germany were sampled, with three orthogonal transects of the field strips and a defined reference position where neither net soil removal nor accumulation occurred. Reforestation took place between the 17th and 19th century. At 0 to 10 cm depth, average SOC content was 28 ± 3 g kg− 1 at ridges, 37 ± 3 g kg− 1 at reference positions and 47 ± 5 g kg− 1 at furrows. SOC stocks were 7 ± 5% lower at ridges and 8 ± 4% higher at furrows than at reference positions. Enhanced C input at furrows through leaf litter accumulation was indicated by higher SOC content in the free light fraction at furrows (10 ± 5 g kg− 1) than at ridges (6 ± 3 g kg− 1), higher specific SOC mineralisation (37 ± 4 μg CO2-C g− 1 SOC at furrows and 31 ± 3 μg CO2-C g− 1 SOC at ridges) and wider C/N ratio at furrows (18 ± 1) compared with ridges (17 ± 1). Buried topsoil under ridges (20 to 33–52 cm depth) did not contain significantly less SOC than corresponding samples at furrows and reference positions. However, SOC content was 0.4 to 0.9 g kg− 1 higher at ridges than at reference positions, indicating long-term preservation of former topsoil SOC by burial under ridges, although enhanced SOC stocks at ridges due to carbon burial could not be significantly confirmed for all sites. It can be concluded that preserved microtopography over centuries and ancient topsoil burial, a legacy of medieval ridge and furrow cultivation, still influences forest SOC spatial distribution and stocks.

This study demonstrates a human impact on the development of active drainage network (ADN) operating during heavy rainfall in a medium-high relief flysch catchment. The ADN was reconstructed with the use of ALS-LiDAR data. The results have revealed that the density of the ADN (11.2 km∙km−2) is c.a. 5 times higher compared to the river system (2.2 km∙km−2) and c.a. 25% of the ADN constitutes man-origin elements (roads, ditches and plough furrows), which are incorporated into the drainage system. The Hortonian’s type of analysis has revealed that man-origin elements significantly change the structure of a natural, river drainage system, and man-origin elements are predominantly attributed to 1st and 2nd order streams, which drain the upper part of the hillslopes. Roughly up to 37% of 1st and 2nd order streams are the man-origin elements of the ADN and those streams drain c.a. 22% of the catchment area. Quantification of the changes in the ADN gave the opportunity to analyze the hydrological response of a catchment. The results have revealed that the reconstruction of flood wave parameters by rainfall-runoff (SCS-CN and GIUH models) hydrological models is more accurate when the Horton’s parameters describe ADN operating during heavy rainfall. It has been revealed that alteration of the ADN influences the flood wave peak predominantly, increasing it up to 11%.

River regulation since the 17th century, large-scale drainage, and intensive farming have seriously transformed soils in the river valleys of Poland. Flood suppression and groundwater lowering have created oxidizing conditions in topsoil and allowed biological activity and plant rooting, which has retarded original stratification of the alluvial substratum. However, ploughing has led to the development of thick humus horizons. In particular, soils with organic topsoil horizons have been changed, i.e. they have lost their initial swampy nature and have undergone an anthropogenic transformation to mineral soils. Despite the long-term agricultural land use, it is still possible to recognize the peaty character of organic matter in some soils and this allows reconstruction of their origin. This study investigated a sequence of soils in the valley of the river Barycz: (i) occasionally flooded, very moist Fluvic Histic Gleysols, with a Murshic organic layer, (ii) weakly drained soils with a high groundwater table, deeply ploughed, where the sandy plough layer contains easily recognizable peat-derived organic material, weakly bound to the mineral fraction (Fluvic Anthromollic Gleysols), and (iii) deeply drained soils, deeply ploughed, where organic carbon content in the plough layer is below 10%, but peat-derived particles of organic matter are still recognizable and are weakly bound to the mineral fractions [(Endogleyic Phaeozems (Anthric) or Endogleyic Umbrisols (Anthric)]. None of the thick plough layers, although intentionally created by humans by mixing the organic layer with underlying sandy material, fulfill the requirements of the anthropogenic diagnostic horizons. Therefore, two new qualifiers are proposed to the WRB classification in relation to the recent addition of the “Murshic” qualifier, namely “Anmooric” and “Atric”, to allow accurately naming the postswampy soils at subsequent stages of their transformation.

A minimum amount of straw is still needed to protect soil from wind and water erosion. To better understand the soil protection effect of straw, the relation of wheat straw displacement and its burial status with plowing speed, tillage depth and the attachment of trash-board was studied. Three controlling factors were evaluated in a field tillage testing, i.e., two types of plow (with and without trash-board), three lengths of straw (100 mm, 150 mm, and 250 mm), and various straw conditions. Straw pieces with specific lengths were prepared before the experiment and used as point tracers to measure the soil and straw displacement. The results indicated that the soil and straw displacements were significantly different but that the two were interrelated. As the length of straw increased, the soil displacement decreased due to the forward and lateral displacements; the straw displacement was always significantly larger than soil displacement, independent of the straw mixtures. Attachment of a trash-board reduced the soil displacement, but had no apparent effect on the straw displacement. Longer straws were less effective to be incorporated into the soil than the shorter ones, and the presence of a trash-board led to higher straw burial performance. The results also indicated that low tillage speed resulted in larger soil fragments and straw displacement with more straw buried. Moreover, longer straw was less effectively buried than shorter straw at the same speed. However, straws neighboring the shear were more extensively displaced than those nearby the share bottom.

Rice is one of the most important crops in the world. It provides food for 40% of the world’s population and 60% of China’s population. Soil nutrients have a significant impact on both agriculture and the environment, particularly with regards to soil fertility, soil quality, and rice production. However, minimal research has been conducted to address spatial patterns of soil nutrients at a large scale within paddy fields. This information is crucial for improving not only soil nutrient management, but also rice yields. Soil surface samples (0–20 cm of plough depth, totalling 8890) were collected from paddy fields to determine the spatial variability of eight soil chemical properties (soil organic carbon (SOC), total nitrogen (TN), available N (AN), total phosphorus (TP), available P (AP), total potassium (TK), rapidly available K (RAK), and slowly available K (SAK)). Inverse distance weighting (IDW) and ordinary kriging methods were applied to produce a continuous soil nutrient surface. Results indicated that soil chemical properties vary substantially. Paddy fields were characterized by high mean concentrations of SOC (19.7 g kg−1), TN (1.91 g kg−1), and AN (164.7 mg kg−1), implying that no additional C and N fertilizer was needed in regions with high SOC and N. SAK and AP demonstrated moderate (36.9%) and weak (96.2%) spatial dependence, respectively, while strong spatial dependence (10.1–13.5%) was observed across the remaining six soil chemical properties. Regional distribution maps of soil chemical properties were produced and ordinary kriging methods interpolated more accurately than the IDW method.

Soil tillage is an anthropogenic factor affecting hydrological processes in agricultural fields. To demonstrate a novel method for increasing mechanistic understanding of the tillage impacts, we combined a process-based three-dimensional (3D) hydrological model with terrestrial laser scanning (TLS) data. This study aimed to (1) exploit high-resolution TLS data to estimate soil surface depression storage (SSDS) and roughness after different soil tillage operations (ploughing, harrowing vs direct drilling) on a heavy clay soil, (2) combine the estimates of SSDS and roughness with a 3D hydrological model to demonstrate the potential of the method in analyzing hydrological impacts of tillage, and (3) evaluate the value and uncertainties in coupling spatial microtopographical data and process-based modeling. The SSDS values showed low mean (0.3–2.9 mm) and rare high values (>5 mm) with clearly the highest variation of SSDS and roughness values in the ploughed conditions. These tillage impacts were reflected in the amounts of surface layer runoff (max. increase 23% due to the SSDS and roughness changes) and drain discharge (max. decrease 8%). The impact on other water balance components was negligible, and factors such as drainage methods and terrain slope were shown to have more control on the water balance. The tillage impacts had also a clear effect on peak surface runoff values. Most (99%) of the hydrological changes were caused by the SSDS variation whereas the roughness had a minor role. The simulations showed that tillage-induced long-term changes on soil hydraulic properties (such as conductivity and macroporosity), which were not detected by the TLS data, can have a high impact on surface layer runoff generation, as these tillage-impacts increased runoff by 25%. While the simulations showed how the various hydrological impacts of tillage can be discerned, a more comprehensive assessment would require more data derived from several sites and tillage conditions.

article i nfo Soil organic carbon sequestration Rooting depth Soil organic carbon stocks Soil sampling depth Soil organic carbon distribution within soil profile is highly influenced by management practices, especially tillage systems where soil environment is altered. Such changes in soil environment will affect soil carbon reten- tion or accumulation in different layers of the soil profile. However, much published research in the area of soil organic carbon (SOC) sequestration focuses on shallow sampling depths within the 0-30 cm tillage zone when determining SOC stocks and sequestration. The objectives of this study are to quantify the SOC stock differences with depth between tillage treatments after 20 years and to determine the appropriate sampling depth when assessing SOC stocks as influenced by management practices. A 20-year moldboard plow (MP), chisel plow (CP) and no-tillage (NT) study was established with a maize-soybean rotation. The 75-cm root zone was sampled in 5-cm intervals to measure SOC stocks. The SOC sequestration, storage, retention and loss were determined for the 0-5 cm, 0-15 cm, 15-75 cm and 0-75 cm layers. The NT treatment did retain more SOC stock than the MP treatment to a 20 cm depth but the SOC stock of the 20-35 cm layer NT system was lower than the MP system. It is recommended that the depth of soil sampling has to include the entire root zone to accurately report SOC stock and the effect of tillage system on change in SOC.

This paper investigates soil stratigraphy of lynchets in sloping lands in eastern Belgium, and rates of their development by comparison to tillage translocation by non-mechanised agriculture. In Belgium, detailed topographical surveys and augerings were carried out at three sites that were under cropland till 1900–1950. Rates and diffusion constants of current non-mechanised tillage erosion were monitored in Ethiopia using tracers, and by precise surveys of tillage steps of known ages. The lynchets in Belgium consist of colluvium that was removed at the upper border of previously farmed plots. Repeated tillage with animal drawn implements results in soil translocation fluxes to the lower plot borders in the order of 11 to 91 kg m − 1 year − 1 (for slope gradients between 0.03 and 0.35 m m − 1 ). The studied lynchets in eastern Belgium would have required cropping agriculture for a total of 217–585 years on steep, and 1037–1867 years on gentle slopes. The establishment of lynchets hence took place without any deliberate action of digging, but due to repeated tillage, even with simple implements, and water erosion. Calculated time spans of tillage indicate that some parts of the study area had already been under cultivation during the Gallo-Roman period, others since the Middle Ages.

Soil water infiltration is one of the most important processes affecting the volume, transport route and water quality of agricultural drainage. Tillage method and depth have also effects on the ability of soil to store water and the furrow irrigation hydraulics of irrigated fields. A study was conducted to evaluate the effect of tillage method and depth on furrow irrigation hydraulics and soil water storage during the dry season at Dire Dawa, Eastern Ethiopia. Treatments in the study included were chisel, moldboard and disk ploughing to 150 mm and 250 mm depths; and “Maresha” (local plough). Data obtained through field measurement and/or observations and laboratory analysis included soil data, irrigation water, advance and recession times, inflow–outflow volumes, available soil moisture, and infiltration rate at each irrigation event. Extending tillage depth from 150 mm to 250 mm significantly increased irrigation infiltration (mm) from 34 to 38%, increased irrigation water advance time from 55 to 75%, increased application efficiency from 33 to 55%, and increased saturated hydraulic conductivity from 23 to 48%; and significantly decreased tail water ratio and distribution uniformity (p < 0.05) in the first two irrigations, but had little effect during the successive irrigations.

The primary objective of this research was to determine the soil erosion rates in cropland of west central Illinois using a magnetic tracer (fly ash) and radio-cesium (cesium-137). The fly ash and cesium-137 accumulation on a stable cropland/hayland summit was determined using a spiral transect. This reference site was used as a baseline and then compared with the fly ash and cesium-137 levels in adjacent cropland landscape positions to estimate loss from erosion. The cesium-137 and fly ash data suggests that cropland lost significant sediment, fly ash and cesium-137 to erosion process especially from the upper and lower backslopes and footslope. The amount and rate of erosion predicted for each cropland landscape position using the fly ash and cesium-137 methods were determine for the 1910 to 1960, 1960 to 2009 and for the entire 100-year time periods. The fly ash and cesium-137 determined erosion amounts and annual soil erosion rate for cropland landscapes positions were highest for the upper and lower backslopes. Past backslope annual erosion rates for three different time periods were 51 Mt ha− 1 yr− 1 or less and above the tolerable soil loss rate of 11 Mt ha− 1 yr− 1 for Hickory soils. However, the predicted fly ash annual erosion rates for the last for the last 50 years using cesium-137 deposition was higher than annual erosion rates for the 1910 to 1960 time period using the difference between the two methods. The reason for the higher erosion rates for the 50 years after 1960 than before was most likely the continued use of moldboard plowing, up and down the slope plowing and the more intensive corn–soybean rotation without forages and small grains. These methods provide a way to document past cropland soil erosion amount and rates for three different time periods (1910 to 1960, 1960 to 2009 and 1910 to 2009).

Tillage practices and depth of plow play an important role in altering the porosity and infiltration capacity of soils and hence surface runoff and soil water availability. A study was conducted to evaluate the effect of tillage method and depth on grain yield and irrigation water use efficiency (IWUE) during the dry season at Dire Dawa, eastern Ethiopia. Treatments for this study included were chisel plow at 150 and 250 mm depth (CH 150 and CH 250 ), and disk plowing to 150 mm and 250 mm depths (DP 150 and DP 250 ); moldboard plow (MB 150 and MB 250 ) and “Maresha” (local plowing) (LP). Grain yield was determined by taking samples from three sections of the central furrow. Grain yields were adjusted to 10% moisture content. It was found that tillage method did not significantly affect the average grain and biomass yield and IWUE of grain and biomass. The grain yield for tillage method treatments averaged from 5325 kg/ha for local plow to 5839 kg/ha for disk plow. The effect of depth of plow on grain yield (kg/ha) ranges from 392 to 7108 for MB 150 and DP 250 , respectively. The IWUE (grain, kg/ha cm) for tillage depth treatments averaged from 16.73 for DP 150 to 30.90 for DP 250 , and their respective IWUE (biomass, kg/ha cm) averaged from 95.4 (MB 150 ) to 124.6 (CH 250 ).

The effects of conservation tillage on profile distributions of soil organic carbon (SOC), total N (TN), and C:N ratios were not well documented in China. The work was conducted at two field experimental sites in the northeast of China. Soils were Cambisols and continuously cultivated with maize (Zea mays L.) for 12 years (Jianping site) and 5 years (Changtu site). Two treatments were conducted at each site and were traditional tillage (TT, i.e., mouldboard plow with residue incorporation) and conservation tillage (CT, i.e., no-tillage with residues left on the soil surface). The responses of SOC and TN stocks to CT differed between the sites and among the soil depths. In the surface soil (0–20 cm), SOC and TN concentrations and C:N ratio were uniformly-distributed under TT. These same response variables decreased with increasing depth under CT. The stratification ratios of SOC for surface to deeper depth (i.e., 0–5 cm:20–40 cm) ranged from 1.5 to 1.8 under CT but only from 1.2 to 1.3 under TT. CT also increased stratification of soil TN and the C:N ratio compared to TT.

The Bashang area, located in the semiarid agropastoral zone, represents a typical degraded ecosystem under intensified human activities. This region has undergone profound land use changes during the past century. Natural grasslands had been progressively cultivated, and subsequently, part of cultivated lands had been abandoned by farmers due to severe desertification. In this study, we collected soil samples (0–20 cm depth) from four farmlands on both flat and gentle slope lands where cultivation had occurred for 0, 8, 30, and 50 years to assess the effects of grassland cultivation on soil degradation. In addition, soil samples were taken and plant species were investigated from eight sites in age sequence of 0- to 50- year-old abandoned field to assess natural restoration process following field abandonment. The results showed that cultivation of grassland result in a significant soil degradation which is manifested by the coarsening in soil texture and the losses in organic C and nutrients. After 50 years of cultivation, soil organic C, total N, and total P concentrations had declined 73–79%, 60–70%, and 67–68% in the 0–20 cm plough layer, respectively. Over half of these losses occurred during the first 8 years of cultivation, and subsequent was slow. After fields were abandoned, vegetation got self-restoration, and plant species composition moved toward that of the natural grassland community with time. Soil organic C, total N, and total P levels gradually improved with increasing years of land abandonment, with a faster restoration rate in the early vegetation recovery stage and a slower rate in the late succession stage. The results suggested that soil degradation may occurred drastically by inappropriate land use and management with a short time, while soil restoration for a degraded ecosystem may take long period of time, especially in this fragile ecosystem. From the perspective of soil resource management and desertification control, conservational tillage and management for farmlands and proper grazing management for recovered grassland should be taken into account in this area.

Summary Man-made soils (plaggen soils) are soils which for centuries were fertilized with a mixture of manure and sods, litter and sand. Pollen analysis of a section from a man-made soil revealed a record of successive vegetations and cultivated plants, comparable with the results of pollen analysis of an adjacent peat, developed near a source of a vanished brooklet. The introduction of Fagopyrum about 1450 A.D. and the application of commercial fertilizers about 1900 A.D. deliver two fixed levels in the soil and peat profiles. The average rate of peat growth and the average rate of the accumulation of the plaggen soil material can be calculated. In this way the base of the plaggen soil is dated about 1350 A.D. Through micromorphological study it is clear that a part of the plaggen material originates from the flood plain of the surrounding riverlets and that a great part of the humification took place in the stable, the manure heap and finally in the plough layer in the field. The major part of the pollen influx comes directly from the crops on the field and only a minor part is derived by air from the surrounding areas. The pollen is preserved mainly in fecal pellets, which is demonstrated by the zonation in the pollen diagram.

Summary Plow layer samples of a heavy loam soil were wetted to different moisture contents and the aggregates so formed were air-dried and dry sieved. The optimal moisture content for aggregate formation corresponded to about 80 % of the field capacity value (FC = pF 2.54); being 25 % (on dry soil weight). When aggregates are prewetted and then mixed with polyvinyl acetate-dibutyl maleate emulsion (Curasol AE), so that the final amount of moisture added to the soil (prewetting + dilution of soil conditioner) also corresponds to 80 % of FC, then the highest aggregate percentage and highest aggregate stability are obtained. The higher the dilution rate of the polyvinyl acetate, the better the penetration and distribution of the soil conditioner in the soil.

Soil erosion in countries with a temperate oceanic climate has received little attention but it is far from negligible in the vineyards of Alsace. Its significance, extent and causes have been determined at a regional scale by investigation and by field observations. The mean annual amount of material lost from the slopes is equivalent to a layer of soil about 6 to 7 mm thick, especially on slopes steeper than 10°. This annual value is extremely variable and reflects differences in soil types and slope angle. This loss is not compensated for by the replacement of the soil since this only amounts to 20 to 30 % of the material lost during catastrophic meteorological events. The cost of replacing lost soil is on average 300 francs per year per viticulturist. The total cost of all the consequences of erosion amounts to 2000 francs per year per affected hectare. Both ploughing and cultivation without tillage are practised in the vineyard. During the second type of cultivation grass mulching is used to prevent soil erosion, but the results are not sufficient to enable conclusions to be drawn about the prevention of erosion. On the contrary this might encourage soil loss in some situations, more than ploughing, by stimulating linear erosion (rilling). Both private and public conservation measures will be necessary if the rate of erosion is to be reduced. However, most viticulturists remain attached to their traditional methods of cultivation.