Short-term effects of double-layer ploughing reduced tillage on soil structure and crop yield

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

Assessing the impact of different irrigation levels on starch potato production

In the view of increasing water demands in agriculture, efficient water use is a key factor in potato production. The aim of this study was to compare two deficit (80% and 90%) and one abundant (120%) gun sprinkler irrigation levels with the longtime used irrigation level of a farmer (100%). Irrigation was supplied during the 2021 growing season on a loamy sand site in Mecklenburg–Western Pomerania, Germany. Yield and tuber quality of the high-amylopectin potato (HAPP) variety “Waxy/Henriette” were assessed in a three-grade tuber size distribution. Five economic indicators were used to assess the suitability of the investigated irrigation levels to secure economic responses. Yield and starch yield did not significantly differ between the 90% (561.1 dt ha−1 and 102.0 dt ha−1) and the 100% irrigation levels (559.1 dt ha−1 and 102.3 dt ha−1), with total production increasing by 2.0 dt ha−1 and starch production decreasing by 0.4 dt ha−1 at the 90% irrigation level. Tuber lesions decreased the economic responses at all irrigation levels. Potentially, 87,469 m3 of irrigation water (125.8 m3 ha−1) could have been saved on the loamy sand starch potato sites of the local farm (695.3 ha) in 2021

Wind erosion after steppe conversion in Kazakhstan

Semi-arid regions of Central Asia suffer from wind erosion due to expanding steppe conversion and unsustainable farming practices. Empirical data from field observations are needed to support the implementation of adapted management. In this study, a mobile wind tunnel was used for the first time in Kazakhstan to assess the soil's erodibility under real conditions. Field experiments were conducted on loamy sands with different initial conditions that are typical for the most erosive time of the year: a bare surface with a cloddy structure after recent steppe conversion, a weak crust on a plot with barley (Hordeum vulgare L.), and a plot with loose material in the rows of maize plants (Zea mays L.). Subsequently, different levels of mechanical stress (low, moderate, high) were considered to analyze the effect of disruptive forces soils experience during field cultivation (light cultivator, disc harrow, tractor tires) on possible soil losses. The results of wind tunnel experiments showed already great differences under initial conditions. The cloddy structure of the recent steppe conservation had the lowest susceptibility against wind erosion due to a good aggregation and a large roughness, resulting in soil loss of 12 g m−2. The plot grown with barley was less affected by wind erosion due to the weak crust, smaller distances between plants, and leaves close to the ground (soil loss of 34 g m−2). Maize was also the most problematic crop in the study area because wind can blow below the plant canopy without considerable resistance during the early growth stages. Additionally, existing deposits in the maize rows from previous erosion events led to the highest soil loss of 1609 g m−2. Mechanical stress by seedbed preparation generally increased the erodible fraction, resulting in higher soil losses (light cultivator: 198 ± 129 g m−2, disc harrow: 388 ± 258 g m−2). The most severe disruption of soil structure occurred on tractor tire tracks, causing a loss of 2767 ± 1810 g m−2. Consequently, the pulverizing effect of tractor tires on dry soil must be considered a serious emission source. Comparing the soil organic carbon content of topsoil and eroded material showed that organic carbon was enriched only in the aeolian sediments of the recently converted plot (+69%). We conclude that soils after steppe conversion need to be treated with particular care from the very beginning so that severe events from the past are not repeated

Wind erosion after steppe conversion in Kazakhstan

Semi-arid regions of Central Asia suffer from wind erosion due to expanding steppe conversion and unsustainable farming practices. Empirical data from field observations are needed to support the implementation of adapted management. In this study, a mobile wind tunnel was used for the first time in Kazakhstan to assess the soil's erodibility under real conditions. Field experiments were conducted on loamy sands with different initial conditions that are typical for the most erosive time of the year: a bare surface with a cloddy structure after recent steppe conversion, a weak crust on a plot with barley (Hordeum vulgare L.), and a plot with loose material in the rows of maize plants (Zea mays L.). Subsequently, different levels of mechanical stress (low, moderate, high) were considered to analyze the effect of disruptive forces soils experience during field cultivation (light cultivator, disc harrow, tractor tires) on possible soil losses. The results of wind tunnel experiments showed already great differences under initial conditions. The cloddy structure of the recent steppe conservation had the lowest susceptibility against wind erosion due to a good aggregation and a large roughness, resulting in soil loss of 12 g m−2. The plot grown with barley was less affected by wind erosion due to the weak crust, smaller distances between plants, and leaves close to the ground (soil loss of 34 g m−2). Maize was also the most problematic crop in the study area because wind can blow below the plant canopy without considerable resistance during the early growth stages. Additionally, existing deposits in the maize rows from previous erosion events led to the highest soil loss of 1609 g m−2. Mechanical stress by seedbed preparation generally increased the erodible fraction, resulting in higher soil losses (light cultivator: 198 ± 129 g m−2, disc harrow: 388 ± 258 g m−2). The most severe disruption of soil structure occurred on tractor tire tracks, causing a loss of 2767 ± 1810 g m−2. Consequently, the pulverizing effect of tractor tires on dry soil must be considered a serious emission source. Comparing the soil organic carbon content of topsoil and eroded material showed that organic carbon was enriched only in the aeolian sediments of the recently converted plot (+69%). We conclude that soils after steppe conversion need to be treated with particular care from the very beginning so that severe events from the past are not repeated

Bodenphysikalische und computertomographische Messungen zur Untersuchung verdichtungsabhängiger Gefügeänderung bei Strip-Till im Vergleich zu Mulchsaat und Direktsaat

Bei Strip-Till (ST), einer besonderen Form der konservierenden Bodenbearbeitung, entstehen kleinräumige Strukturunterschiede, da die Bodenbearbeitung nur innerhalb der Saatreihen (STIS) stattfindet, während den Boden zwischen der Saatreihen (STZS) unbearbeitet bleibt. Diese Differenzierungen werden hier im Vergleich zu Mulchsaat (MS) und Direktsaat (DS) aus kombinierten klassischen bodenmechanischen und computertomographischen (CT) Methoden auf einem Tschernosem (Textur 0-30 cm: stark toniger Schluff) untersucht. Zusätzlich zu den Parametern Trockenrohdichte (TRD) und gesättigte Wasserleitfähigkeit (Jahre: 2012, 2014, 2015) in 2-8 und 12-18 cm Tiefe wurden Drucksetzungsversuche (Jahr 2015, 12-18 cm Tiefe, 5-550 kPa) durchgeführt. Die mechanische Vorbelastung wurde an den Druck-TRD-Kurven bestimmt. Ferner wurden CT-Bilder und CT-Parameter (Porengröße, Porosität, Konnektivität, Anisotropie) derselben Bodenproben ermittelt. Von 2012 bis 2015 kam es zu einer Erhöhung der TRD bei STZS und DS im Vergleich zu STIS und MS, die in 2-8 cm Tiefe stärker ausgeprägt war als in 12-18 cm Tiefe. STZS zeigte trotz höherer TRD eine höhere gesättigte Wasserleitfähigkeit im Gegensatz zu STIS aufgrund erhöhter Regenwurmaktivität. Die mechanische Vorbelastung war bei STZS signifikant höher als bei STIS. Die CT-Bilder und die CT-Parameter unterstützen die beobachtete mechanisch stabilere Bodenstruktur unter STZS aufgrund der fehlenden Bodenbearbeitung. Andererseits erzeugte die Bodenbearbeitung bei STIS ein lockeres, poröses und konnektives Bodengefüge. Bei allen Varianten führte der Anstieg der TRD, durch zunehmende Belastung, zu einer Zunahme der Anisotropie, während die übrigen CT-Parameter abnahmen. Es konnte gezeigt werden, dass ST die Vorteile von DS und einer tieferen Grundbodenbearbeitung vereint, da einerseits MS und STWS und andererseits STBS und DS sehr ähnliche Bodeneigenschaften aufweisen. Daneben können die CT-Parameter unser Verständnis über das Funktionsverhalten der Böden bei unterschiedlicher Bodenbearbeitung verbessern

Site-specific seeding using multi-sensor and data fusion techniques : a review

Site-specific seeding (SSS) is a precision agricultural (PA) practice aiming at optimizing seeding rate and depth, depending on the within field variability in soil fertility and yield potential. Unlike other site-specific applications, SSS was not adopted sufficiently by farmers due to some technological and practical challenges that need to be overcome. Success of site-specific application strongly depends on the accuracy of measurement of key parameters in the system, modeling and delineation of management zone maps, accurate recommendations and finally the right choice of variable rate (VR) technologies and their integrations. The current study reviews available principles and technologies for both map-based and senor-based SSS. It covers the background of crop and soil quality indicators (SQI), various soil and crop sensor technologies and recommendation approaches of map-based and sensor-based SSS applications. It also discusses the potential of socio-economic benefits of SSS against uniform seeding. The current review proposes prospective future technology synthesis for implementation of SSS in practice. A multi-sensor data fusion system, integrating proper sensor combinations, is suggested as an essential approach for putting SSS into practice

"Princesses are beautiful, princes are brave" : Childrens books by a gender perspective

The aim of the study is to examine characters in books for children through a gender perspective. Partly I want to examine how female and male gender are constructed, partly how gender norms reproduce and/or challenges. This study proceeds from the following questions: ● How are female and male characters described in the books? ● What actions do female and male characters perform? ● How do the characters act towards characters of the opposite gender? The investigation is based on text analysis and the material consists of seven books for children. The theoretical basis is based on Butlers theory “gender performativity”, Hirdmans gender theory and Nikolajevas scheme of qualities of gender stereotypes. The result showed that the characters often seem to have gender stereotypical qualities. Female characters are more likely to behave as both male and female gender performativity and the male gender performativity and qualities of gender stereotypes are considered more valuable than female. To challenge gender norms we need to study and discuss literature, otherwise the gender norms will be maintained

"Princesses are beautiful, princes are brave" : Childrens books by a gender perspective

The aim of the study is to examine characters in books for children through a gender perspective. Partly I want to examine how female and male gender are constructed, partly how gender norms reproduce and/or challenges. This study proceeds from the following questions: ● How are female and male characters described in the books? ● What actions do female and male characters perform? ● How do the characters act towards characters of the opposite gender? The investigation is based on text analysis and the material consists of seven books for children. The theoretical basis is based on Butlers theory “gender performativity”, Hirdmans gender theory and Nikolajevas scheme of qualities of gender stereotypes. The result showed that the characters often seem to have gender stereotypical qualities. Female characters are more likely to behave as both male and female gender performativity and the male gender performativity and qualities of gender stereotypes are considered more valuable than female. To challenge gender norms we need to study and discuss literature, otherwise the gender norms will be maintained

"The cowboy captures cows and suchlike" : Reading comprehension strategies in school year 2 by the teaching material "A Reading Class"

The aim of the study is to examine which reading comprehension strategies by the teaching material "A Reading Class" a teacher in second grade tutors about and how the teacher tutors, and which reading comprehension strategies pupils in second grade state that they use when they read on their own, and in what whey they use those reading comprehension strategies. Therefore this study proceeds from the following questions: Which reading comprehension strategies does the teacher tutor about and how does the teacher tutor about those strategies? Which reading comprehension strategies do the pupils state that they are using when they are reading on their own? How do the pupils use the reading comprehension strategies when they read on their own, according to themselves? The investigation is based on three observations of the tutoring about reading comprehension strategies and six interviews with a total of eleven pupils. The theoretical basis is composed of theories about the sociocultural perspective, scaffolding, zone of proximal development and reciprocal teaching. The result showed that the teacher tutored about the reading comprehension strategies: predicting, clarifying, questioning and summarizing. She encouraged the pupils to create inner images and to make text connections (text-to-self, text- to-text, text-to-world). She tutored about the strategies by the model "think aloud". The pupils seem to use the strategies predicting and clarifying most frequently when they are reading on their own but also creating inner images. For example, they use the strategy predicting when they are choosing books to read and the strategy clarifying when they don’t understand words while they are reading. A lot of the pupils seem to have trouble explaining how to use the strategy summarizing, and also seem to find it hard to summarize after reading, but skillful readers seem to accomplish that better than less skillful readers. The pupils seem to use the reading comprehension strategies in greater occurrence when they are reading on their own than they are aware of

"The cowboy captures cows and suchlike" : Reading comprehension strategies in school year 2 by the teaching material "A Reading Class"

The aim of the study is to examine which reading comprehension strategies by the teaching material "A Reading Class" a teacher in second grade tutors about and how the teacher tutors, and which reading comprehension strategies pupils in second grade state that they use when they read on their own, and in what whey they use those reading comprehension strategies. Therefore this study proceeds from the following questions: Which reading comprehension strategies does the teacher tutor about and how does the teacher tutor about those strategies? Which reading comprehension strategies do the pupils state that they are using when they are reading on their own? How do the pupils use the reading comprehension strategies when they read on their own, according to themselves? The investigation is based on three observations of the tutoring about reading comprehension strategies and six interviews with a total of eleven pupils. The theoretical basis is composed of theories about the sociocultural perspective, scaffolding, zone of proximal development and reciprocal teaching. The result showed that the teacher tutored about the reading comprehension strategies: predicting, clarifying, questioning and summarizing. She encouraged the pupils to create inner images and to make text connections (text-to-self, text- to-text, text-to-world). She tutored about the strategies by the model "think aloud". The pupils seem to use the strategies predicting and clarifying most frequently when they are reading on their own but also creating inner images. For example, they use the strategy predicting when they are choosing books to read and the strategy clarifying when they don’t understand words while they are reading. A lot of the pupils seem to have trouble explaining how to use the strategy summarizing, and also seem to find it hard to summarize after reading, but skillful readers seem to accomplish that better than less skillful readers. The pupils seem to use the reading comprehension strategies in greater occurrence when they are reading on their own than they are aware of