Search

A rotary tiller is a common tillage tool for straw incorporation in an intensive tillage system. However, rotary tillage for seedbed preparation in dense-straw mulching conditions experiences high torque and poor performance of straw incorporation. Nowadays, a great deal of studies have been focused on mimicking the morphological features of low-resistance animals to improve the performance of soil-engaging tools. Accordingly, the present study investigated the performance of three C-type rotary blades (i.e., conventional, serrated, and biomimetic) under three straw lengths (50, 100, and 150 mm) for incorporation of straw into the field using an in situ field tillage testing bench. Compared to the conventional and serrated blades, the biomimetic blade had lower straw displacement (decreased by an average of 50 mm and 7 mm, respectively), higher straw burying rate (increased by an average of 5.2% and 7.8%, respectively), better straw distribution (decreased by an average of 9.1% and 10.4% on the coefficient of variation, respectively), as well as lower torque and power (decreased by an average of 3.3 N·m and 4.4 N·m, respectively) under all straw lengths. The improved performance of the biomimetic blade could be attributed to the fact that its typical teeth configuration was designed by mimicking the smooth arc of the mole-rat’s claw. These results demonstrated that the biomimetic-designed blade could be a better option for incorporating dense straw into the field conditions.

As brown mushrooms are both delicious and beneficial to health, the global production and consumption of brown mushrooms have increased significantly in recent years. Currently, to ensure the quality of brown mushrooms, selective manual picking is required, and the delicate surface of the mushrooms must not be damaged during the picking process. The labor cost of picking accounts for 50–80% of the total labor cost in the entire production process, and the high-humidity, low-temperature plant environment poses a risk of rheumatism for the laborers. In this paper, we propose a novel underactuated gripper based on a lead screw and linear bearings, capable of operating with flexible force control while simultaneously measuring the diameter of the mushrooms. The gripper features three degrees of freedom: lifting, grasping, and rotation, and enabling it to approach, grasp, and detach the mushroom. A thin-film force sensor is installed on the inner side of the fingers to achieve accurate grip force measurement. The use of a PID algorithm ensures precise grip force control, thereby protecting the brown mushrooms from damage. Experimental results demonstrate that the proposed gripper has a static grasping force error of 0.195 N and an average detachment force overshoot of 1.31 N during the entire picking process. The in situ measurement of the mushroom diameter achieves 97.3% accuracy, with a success rate of 98.3%. These results indicate that the gripper achieves a high success rate in harvesting, a low damage rate, and accurate diameter measurement.

In order to measure wheat yield and wheat spike phenotypes, the grain number of wheat spikes is counted manually at present, but acquiring the grain number of wheat spikes is laborious and time-consuming. Counting the grain number of wheat spikes with an image processing method is promising, yet the application of this method is flawed due to its low accuracy. In this work, images of wheat spikes were collected and processed with technical procedures, including image cropping, image graying, histogram equalization, image binarization, eroding operation, removing small objects, filling image holes, revolving vertical spikes, cutting off stems, and removing stems. Wheat stems in binary images were eliminated by the sum pixels method, and the morphological characteristic parameters of the image areas of wheat spikes and lengths of wheat spike axes were calculated. Mathematical models relating the image areas of wheat spikes and lengths of the wheat spike axes to the grain number were established, and the mathematical models were verified. The results showed that the characteristic parameters of the image areas of wheat spikes and the lengths of the wheat spike axes for the spike images were linear relative to the grain number, and the maximum determination coefficients R2 were 0.9336 and 0.9012, respectively. The maximum determination coefficients R2 for the practical and predicted grain numbers were 0.9552 and 0.9369, respectively, and the minimum average absolute error was 2.3, while the average relative error for the mathematical models was 5.65%. The mathematical models relating the image areas of wheat spikes and the lengths of the wheat spike axes to the grain number were practical and accurate, and the mathematical model comparing the image area of wheat spikes and the grain number was superior to that comparing the length of the wheat spike axis and the grain number. The grain number of wheat spikes could be acquired accurately and quickly by the image processing method extracting the characteristic parameters of wheat spikes.

The advancement of agricultural mechanization necessitates precise and standardized classification based on technical characteristics to enhance green, efficient, and high-quality development. The current lack of scientific and standardized definitions and classifications for various types of agricultural machinery has become a bottleneck, complicating the machine selection and affecting the compatibility of the machinery with optimized field operations. To address this complexity, we propose a comprehensive classification method that integrates principal component analysis (PCA), cluster analysis, and the qualitative analysis of the functional components for defining and scientifically classifying harvesters. The key functional and technical properties of harvesters were analyzed, and eight primary parameters (machine weight, cutting width, feed rate, rated power, overall machine length, width, height, and working efficiency) were selected, supplemented by nine key functional components (walking mechanism, cutting device, threshing device, separating device, cleaning device, grain collecting device, grain unloading device, cabin, and track size). In the first step, principal component analysis was performed to reduce the dimensionality of the parameters, yielding three principal components with contribution rates of 41.610%, 28.579%, and 15.134%, respectively. One primary parameter from each component was selected for further analysis. In the second stage, Q-type cluster analysis classified the harvesters based on the squared Euclidean distance between the operational parameters, resulting in three classes of harvesters. Finally, functional component analysis provided detailed insights, further refining the classification into four major categories: mini, small, medium, and large harvesters. The results of this work provide a scientific basis for the definition and classification of the harvester products available on the market. This method offers a robust framework for the rational selection and planning of agricultural machinery, promoting sustainable mechanization with a focus on technical parameters and functional attributes.

Explaining the physiological and ecological effects of wheat population density can provide new research methods for field crop production. A three-year field trial under drill single-seed seeding was conducted, which used three different intra-row seed-seedling spacings to quantitatively analyze the density effect from three perspectives—population, individual plant, and single-stem panicle—at the winter wheat harvest. The results showed that year and density had significant effects on both the population and individual plant yield (p < 0.05), as well as on some yield components and biomass indicators. The interaction between planting density and annual climate was found only in the number of grains for both the entire population and individual plants. With the increase in planting density, the CI gradually increased, inhibiting the growth of individual plants and leading to a negative impact on monoculture wheat yield. The drill single-seed seeding method can provide a basic experiment condition for analyzing the density effect. The density effect of wheat populations originates from intraspecific competition, which mainly affects the growth of individual plants. Research based on the analysis of density effects from the perspectives of population, individual plants, and single-stem panicles can provide a methodological reference for precision agriculture.

Root fractal analysis is instrumental in comprehending the intricate structures of plant root systems, offering insights into root morphology, branching patterns, and resource acquisition efficiency. We conducted a field experiment on paddy–wheat root systems under varying nitrogen fertilizer strategies to address the need for quantitative standardization in root fractal analysis. The study evaluated the impact of nitrogen fertilizer heterogeneity on root length and number. We established functional relationships and correlations among root fractal characteristics and root length across different box dimension scales and various root placement angles at 2.5, 5, 10, 20, 40, and 80 box dimension scales. Results indicated that nitrogen fertilizer had a limited impact on paddy–wheat axile roots, with a coefficient of variation below 0.35 among samples. Box dimension scale influenced 3D fractal dimension (FD) and fractal abundance (FA), with strong correlations (>78%) among 3D fractal features and low sample errors (0.76 for FA and >0.5 for FD) and low sample errors (

Rotary tillage facilitates conservation agriculture in rice-based crop farming systems through minimal soil disturbance for seedbed preparation and crop residue management. However, efficiency of rotary tiller blades is hampered by degraded paddy soils and excessive crop residue conditions. Biomimetics presents an edge in the optimisation design of cultivation tools and can be employed to improve the efficiency of rotary tiller blades. This study was designed to evaluate the adaptability and performance of biomimetic rotary tiller blades inspired by the geometric structure of a mole rat’s claw. Field experiments were conducted to evaluate the blades’ torque and power requirements, soil fragmentation, displacement characteristics, and the rate of straw incorporation at three tillage depths (i.e., 40, 70, and 100 mm). Results revealed that the biomimetic blades minimised torque by up to 21.05%, had lower specific power requirements, and produced finer tilths with granular and more even clod sizes than conventional blades. It also achieved more redistribution of topsoil and improved the straw burial rate. The biomimetic rotary tiller blades are thus energy-efficient and can improve soil structure and the quality of seedbeds, besides managing crop residues through incorporation, and therefore advance conservation tillage in intensive farming systems.

Assessing the energy cycle and greenhouse gas (GHG) emissions of wheat production in small Egyptian farms is essential to improve wheat productivity to meet population growth and achieve sustainable development. This study aims to compare wheat production in terms of energy use and GHG emissions for different scenarios in the Delta of Egypt and to use Data Envelopment Analysis (DEA) to optimize the wheat production system. Three common scenarios of the wheat production system (S-I, S-II, and S-III) from old lands with one scenario (S-IV) from newly reclaimed land were included in the study. Data were collected from small farmers through a face-to-face questionnaire and interviews in 2022–2023. The results showed that the third scenario (S-III) in the old lands had the lowest input energy consumption (42,555 MJ ha−1) and the highest output energy (160,418 MJ ha−1), with an energy use efficiency of 3.770. In comparison, the input and output energy for the newly reclaimed scenario (S-IV) were 37,575 and 130,581 MJ ha−1, respectively, with an energy use efficiency of 3.475. S-III was an optimum scenario due to its high energy indicators, such as energy productivity of 0.173 kg MJ−1. The total GHG emissions of S-III were the lowest in old lands with a value of 1432.9 kg CO2-eq ha−1, while S-IV had 1290.2 kg CO2-eq ha−1. The highest GHG emissions input was diesel fuel for machinery and irrigation, followed by manure, chemical fertilizers, and agricultural machinery use. Using mechanization in most farming operations for S-III and S-IV led to decreased losses of agricultural inputs with increasing outputs (yield and straw). Therefore, using them in wheat farming practices is recommended to increase the wheat farming system’s energy efficiency and GHG emissions.

As an advanced agricultural production technology, conservation tillage has been developed rapidly and adopted widely for many crops all over the world, but challenges remain with regard to dealing with excessive residues, especially for intensive rice–wheat rotation systems. Most studies to date have been based on a single type of tool and the indoor bin test to explore its performance. Accurate field test data on the tillage performance of different types of tools for conservation tillage are lacking in this area. In this study, five tillage tools were tested in a paddy field with plenty of crop residues to compare their performance. They were three vertical discs with plain disc (PD), notched disc (ND), and rippled disc (RD) and two disc coulters with plain disc coulter (PDC) and notched disc coulter (NDC). All five tools were tested using a specific field test rig at two different working depths of 70 and 100 mm. Tillage forces, straw cutting efficiency, soil disturbance width, and soil cutting depth were measured. The results showed that tool geometry and working depth had a significant impact on tillage performance. The vertical disc performed a higher average straw cutting efficiency, as well as lower tillage forces and lower soil disturbance width than the disc coulter. For straw handling and furrowing operations, RD had the highest straw cutting efficiency, moderate tillage force, and appropriate soil disturbance width among the five tools. For all five tools, the 100 mm working depth results in 40% higher draught force, 39% greater vertical force, and 18% higher straw cutting efficiency on average. For no-tillage seeding in the intensive rice–wheat rotation system, the RD would be a more suitable rotary tool for conservation tillage practice.

In order to clarify the mechanism of tiller–soil interaction in the process of strip rotary tillage, this paper conducted a simulation and experimental research on four blade configurations composed of three rotary blades (bent C, straight and hoe) at three rotation speeds (280, 380 and 510 rpm). The study found that the soil throwing characteristics of the blades are the key factors affecting the quality of tillage. The increase in the rotation speed not only improved the soil breaking effect, but also enhanced the phenomenon of soil throwing and then led to a reduction in the soil backfill. In the BC configuration (combination of four bent C blades), the bent C blades showed the best soil throwing characteristics and created the best soil fragmentation. However, due to the obvious side throwing of the soil, the backfill effect of soil fragmentation was the worst. The backfill rate was only 8% when the rotation speed was 510 rpm and could not allow reaching the required seed–soil contact during sowing. The hoe blades in the HC configuration (combination of four hoe blades) could collect part of the soil fragments and throw them towards the direction of the machine during the cultivation process, which led to a good soil breaking effect and a low soil side throwing rate. When the rotation speed was 510 rpm, 36% of the soil was backfilled into the seedbed. In the SC configuration (combination of four straight blades), the straight blades could well control the scattering of the side-thrown soil fragments. At a super-high rotation speed (510 rpm), the side throwing rate was only 70%, and the backfill rate was as high as 60%. However, the soil fragments created by the blades were too large (average soil block diameter > 40 mm) and could not form a loose and finely broken seedbed environment. The MC configuration (combination of two straight blades and two hoe blades) benefited from the combination of straight blades and hoe blades, offering outstanding advantages for backfill and soil fragmentation. Therefore, under the condition of a centralized configuration of field surface straw, it is recommended to use the MC configuration of the wheat rotary strip–till planter for cohesive paddy soil.

The introduction of ridge tillage and beans as a cover crop was investigated as a means of management for mitigating soil erosion and increasing the physical functionalities of soil. In a completely randomized design, four treatments were applied to twelve plots, three with ridges introduced (T1), three with beans as the cover crop (T2), three with cover crops combined with ridges (T3), and another three as controls without intervention (T4). Four physical properties were monitored, i.e., soil moisture content, bulk density, infiltration rate, and aggregate stability. Data were collected from two seasons with beans as the cover crop, with each season lasting three months. The results showed that T3 resulted in the highest soil moisture content at 34.87 ± 6.78%, followed by T2 and T1 with 34.20 ± 0.65% and 32.65 ± 1.71%, respectively, while T4 had the minimum value of 28.28 ± 5.30%. The bulk density of the soil was found to be lowest at T2 and T3, both having a value of 0.92 g cm−3 with standard deviations of ±0.03 and ±0.11, respectively. This was followed by T1 with 0.98 ± 0.05 g cm−3 while T4 had the highest bulk density of 1.17 ± 0.13 g cm−3. A similar trend was observed for both the basic infiltration rate and aggregate stability, except that, in terms of the latter, T1 was ranking second after T3, with 64.07% of water stable aggregates greater than 0.25 mm diameter. The interventions introduced in coffee plantations had significant effects on the bulk density and infiltration rate; however, there was no significant difference in the moisture content and aggregate stability. Further investigation is needed to quantify the environmental effects of these interventions, e.g., greenhouse gas emissions and yields.

Subsoiling (SS) is an important technology in conservation tillage, but soil-disturbance characteristics in the SS are rarely described. Research on soil-disturbance characteristics during SS is conducive to the design and optimization of subsoilers, which provides a basis for reducing draft force and energy consumption. This study conducted SS experiments at five different tillage depths in the field with a specific field in situ test-rig facility, and in situ videotaping was made from five positions during SS. The microrelief test, draft force test, disturbance cross-section test and disturbance process analysis were conducted after SS. The results showed that draft force increased with tillage depth as a quadratic function. Soil displacement parameters and soil crack parameters extracted from the video of SS were significantly correlated with tillage depth, which could be used for a quantitative description of the paddy soil-disturbance characteristics. Cross-sectional area showed a trend of “increasing then decreasing” with increasing tillage depth, reaching a maximum at a tillage depth of 20 cm. When the tillage depth was greater than 20 cm, the bottom of the disturbing boundary formed a “mole cavity”. Fallback rate was used to describe the change in disturbed height or width during and after SS, which exceeded 100% at maximum. The surface roughness of microrelief and the size of the average clods reached the maximum at tillage depth of 20 cm. Considering the shallow cultivation layer of paddy soil in rice–wheat rotation, the recommended tillage depth of 20 cm could achieve maximum soil disturbance and minimum energy consumed.

Agricultural production can achieve sustainability by appropriately applying agricultural mechanization, especially in developing countries where smallholding farmers lack sufficient agricultural machinery for their farming operations. This paper aimed to study the extent to which small-, medium-, and large-scale farms in the Delta of Egypt use agricultural mechanization in their wheat crop farming operations. K-means clustering was used to aggregate and analyze the scenarios implemented by farmers for wheat cultivation so as to suggest guidelines for each cluster of farmers on how to mechanize their indoor wheat agricultural operations to maximize production. The study is divided into two parts: Firstly, data were collected regarding the percentage of small, medium, and large farms; the cultivated area of wheat crops in small-, medium-, and large-scale farms; and the size of tractors, as an indicator of the mechanization available in the governorates of Egypt’s Delta. Secondly, data were collected through a questionnaire survey of 2652 smallholding farmers, 328 medium-holding farmers, and 354 large-holding farmers from Egypt’s Delta governorates. Based on the surveyed data, 14, 14, and 12 scenarios (indexes) were established for small-, medium-, and large-scale farms, respectively, related to various agricultural operations involved in wheat crop production. These scenarios were analyzed based on the centroids using K-means clustering. The identified scenarios were divided into three clusters for the three levels of farms. The data obtained showed the need for smallholding farmers to implement mechanization, which could be achieved through renting services. These findings, if implemented, would have huge social and economic effects on farmers’ lives, in addition to increasing production, saving time and effort, and reducing dependence on labor.

Strip rotary tillage seeding technology has been widely used in rice–wheat rotation system, benefiting the economy greatly. The purpose of farming is to create a comfortable seedbed environment for crop growth. Therefore, it is necessary to consider the effects of tillage methods on wheat root configuration and growth trend in the research of strip tillage, instead of just focusing on optimizing the shape of tillage tools, sowing methods, and soil fragmentation. To clarify the effects of different tillage methods on crop root growth trends, a two-year wheat planting experiment was carried out. Strip tillage (ST1 and ST2) and full width tillage treatment (FT) were designed, 3D models of root structure and soil on the surface of the seedbed wall were established, and four quantitative indexes were proposed: soil surface roughness of seedbed wall (SR), difference coefficient of root soil space occupation (P), difference coefficient of root angle expansion trend (PA), and difference coefficient of root length expansion trend (PL). The results showed that the cultivation method directly affects the growth trend of wheat roots. The wheat roots tended to grow along the inter-specific direction under ST treatment on the 14th day, and the average P, PA, and PL were as high as 38, 43, and 55, respectively. The SR produced by ST1 treatment was 70% lower than that of ST2 treatment, suggesting ST1 treatment had more serious restrictions on root growth. P, PA, and PL in ST1 treatment were 38.5%, 14%, and 43% higher than those in ST2 treatment within 14 days, respectively. This paper briefly explains the effects of tillage methods on the growth trend of wheat roots, provides new methods and technologies for the rapid and effective acquisition of soil surface information, solved the problem of the trend of root expansion being difficult to quantify, and provided a new direction for the optimization of tillage methods.

Field-based phenotyping (FBP) of crop root system architecture (RSA) provides a way to quantify the root growth and distribution in field with a smaller scale. Studies on a better understanding of the interrelations between field crop root physiological traits, root developmental phases and environmental changes are hindered due to deficiency of in situ root system architecture testing and quantitative methods for field crop. The present study aimed to propose a protocol for field-based wheat root system architecture with technical details of key operational procedures. Phenotyping of RSA traits from root spatial coordinate data acquisition and visualization software presented scaled illustrations of wheat RSA dynamics and root developmental phases which also revealed the root topological heterogeneities, either within a plant or among individuals. Percentage of horizontal and vertical soil coverage by root showed that root foraging capability along soil depth was better than within the horizontal dimension. In brief, our data indicated that FBP of wheat RSA could be achieved using the protocol of data-driven model-assisted phenotyping procedure. The proposed protocol was demonstrated useful for FBP of RSAs. It was proved effective to illustrate the topological structures of the wheat root system and to quantify RSA-derived parameters, this could be a useful tool for characterizing and analyzing the structural distortion, heterogeneous distribution and the soil space exploration characteristics of wheat root. Keywords: Field-based phenotyping (FPB), Data-driven model-assisted, Paddy-wheat root system architecture, FBP protocol

Conventional soil-tool interaction has been upgraded to straw-soil-tool interaction due to plenty of straw remains in the field after harvesting. Understanding the straw-soil-tool interaction relationship and quantifying the straw movement and distribution characteristics at various tillage operation parameters is critical for straw management and the design of tillage tools. Here, in order to investigate the interactive effects of key operation parameters on the displacement and burial of straw, a specific field test rig was developed to perform straw movement test. According to the singe-factor test and multifactor interactive experiment, we investigated the effect of straw length, tillage depth and rotary speed on straw movement, and established a mathematical model between operation parameters and straw movement. The results showed that the significant order of the influence on the displacement and burial of straw was as follows: the tillage depth, the straw length, the rotary speed. As determined by response surface analysis, the optimal combination of parameters for straw incorporation was straw length of 5 cm, tillage depth of 13 cm, and rotary speed of 320 rpm, and the corresponding straw burial rate and straw displacement were 95.5% and 27.6 cm, respectively. The relative errors of the optimization results are less than 5%. These results indicated that the mathematical model can be used to predict and evaluate straw movement. Therefore, it is feasible to enhance the straw incorporation performance by a reasonable setting of operation parameters, which may provide a comprehensive strategy to improve the working quality of tillage tools.

High-yielding agriculture in an intensive rice–wheat rotation system leads to plenty of residues left in the field after harvest, which is detrimental to seeding operation, seed germination, and early plant growth. Some residue thus needs to be incorporated into the soil. Providing the relationship between tillage operations and residue incorporation and establishing a mathematical model play important roles in residue management and the design of tillage machinery. In order to obtain detailed data on the interaction between residue incorporation and tillage operations, a multifunctional field-testing bench with precise parameter control was developed to assess residue incorporation characteristics of rotary tillage, and we investigated the effects of straw length, stubble height and rotary speed on residue incorporation. Three experimental factors affecting residue incorporation performance were studied, i.e., six lengths of straw (30–150 mm), four heights of stubble (50–200 mm), and three rotary speeds (240–320 rpm). Chopped straw and stubble with certain sizes were prepared for the test, and we measured the burying rate and distribution uniformity of residue after rotary tillage. The results indicated that straw length, stubble height, and rotary speed all impact residue incorporation quality. The burying rate and distribution uniformity of residue decreased with the increase in straw length and stubble height; a lower rotary speed parameter buried less residue and distributed it with worse uniformity than a higher one. It is suggested that farmers determine the straw length and stubble height at the stage of harvest according to the required burying rate and distribution uniformity of residue.

Poor shelling quality degrades the performance and profit of the peanut industry. The Hertz theory and the wear resistance experimental method were applied to identify a highly wear-resistant material guaranteeing a low mechanical damage rate (MDR) of peanut kernels. The Box–Behnken design method was applied in the experiment to illustrate the influence of the material’s elastic modulus (X1), radius of curvature of the key parts (X2), rotating speed of the shelling drum (X3), and clearance between the shelling drum and concave screen (X4) on MDR and shelling efficiency (SE). Depending on the analysis of variance, the weights of the influential factors were observed as X1 > X3 > X4 > X2. The mathematical models of MDR and SE were derived from the least squares’ method, and four-dimensional slice diagrams of the three most significant factors were used to illustrate the trends of MDR and SE. A multi-objective analysis provided the optimal combination of parameters as: X1 = 10 MPa, X2 = 12.77 mm, X3 = 277.48 r/min, and X4 = 24.24 mm, yielding MDR = 4.89% and SE = 97.91%. The results were further verified by a production trial test, proving that the proposed solution with the selected material, machine design, and working parameters were effective in improving peanut shelling quality.

A field experiment was conducted to study the effects of different tillage methods, and their interaction on the dynamic changes of straw decomposition rate, mechanical properties, and micro-structure of the stalk. A nylon mesh bag technique was used. An obvious change was observed in the decomposition rate of straw, and its mechanical, and micro-structural properties. The decomposition rate of straw was increased in all tillage treatments. Specifically, it increased consistently in conventional and dry rotary tillage, and sharply in wet rotary tillage. Furthermore, for all tillage, the mechanical properties like shear and bending strengths decreased sharply while compressive strength first decreased linearly and then increased, whereas the micro-structure of wheat straw showed a fluctuating trend, i.e., it changed neither regularly nor consistently over time. Moreover, the micro-structure of the stalk explained the morphological changes to the straw that returned to the field, which may impact the mechanical properties. However, these changes could not explain the degradation trend of straw directly. The findings of the study could be used as a theoretical reference for the design of tillage and harvesting machinery keeping in view soil solidification and compaction dynamics.

This study aimed to explore the release rate (RR) of wheat straw nutrients during straw return to a paddy field and examined the possible relationship between wheat stalk shear strength and the content of the remaining components in wheat straw. We used the nylon mesh bag technique to study the decomposition of straw nutrients such as total organic carbon (TOC), total nitrogen (TN), total phosphorus (TP), total potassium (TK), lignin, and cellulose over time. During the time span of 0−90 days, results showed a rapid decomposition rate with a diverse trend under different tillage operations. Furthermore, the decomposition rate was higher under the plough (PRP) conditions than under dry conditions (RP) or water rotation (PR). Moreover, under PRP conditions, the RR of TOC, TK, lignin, and cellulose increased, while the RR of TK was higher than 95% initially and then increased slightly. However, the carbon to nitrogen ratio was first increased and then decreased; similarly the RR of TP first increased and then decreased; a fluctuating pattern was observed for TN. Additionally, we found a strong correlation between wheat stalk shear strength and the remaining contents of lignin, hemicellulose, and cellulose, with R2 ≥ 0.91, which was higher than 0.82 after computing adjustments. Furthermore, the changing trend of nutrients and components and the relationship between shear strength and the content of the remaining components in wheat straw were used to evaluate the release characteristics of nutrients under straw return. The potential effects of the straw shear strength on soil mechanical properties were determined, providing a remarkable opportunity for acquiring nutrients for sustainable application of soil.

A two-year field study was conducted to investigate the performance of a lightweight trash-board moldboard plow (with and without a trash-board), as influenced by stubble height and water content. Both fields were measured for the performance of a trash-board moldboard plow when used during the optimization of the plowing depth, the water content, and the reaction forces. The results showed that in the first year, when a trash-board was required, the results were significantly different. The fields had lower draft and reaction force in the soil with only stubble height, which was greater than that in the soil with dense straw for all water content levels. This was also observed in the second year for the whole depth. This study shows that the moldboard plow with a trash-board provided minimum draft and reaction forces with only straw and heavy straw. The results indicate that straw nearby shear significantly increased displacement for all treatments, with variance of straw nearby moldboard. Hence, the results verify that a trash-board continuously created large soil fragmentation with different water content. Straw labels create a position of straw which also allows for better results. It is important to install trash-boards with the moldboard plow for heavy straw incorporation.

Rotary tillage facilitates conservation agriculture in rice-based crop farming systems through minimal soil disturbance for seedbed preparation and crop residue management. However, efficiency of rotary tiller blades is hampered by degraded paddy soils and excessive crop residue conditions. Biomimetics presents an edge in the optimisation design of cultivation tools and can be employed to improve the efficiency of rotary tiller blades. This study was designed to evaluate the adaptability and performance of biomimetic rotary tiller blades inspired by the geometric structure of a mole rat's claw. Field experiments were conducted to evaluate the blades' torque and power requirements, soil fragmentation, displacement characteristics, and the rate of straw incorporation at three tillage depths (i.e., 40, 70, and 100 mm). Results revealed that the biomimetic blades minimised torque by up to 21.05%, had lower specific power requirements, and produced finer tilths with granular and more even clod sizes than conventional blades. It also achieved more redistribution of topsoil and improved the straw burial rate. The biomimetic rotary tiller blades are thus energy-efficient and can improve soil structure and the quality of seedbeds, besides managing crop residues through incorporation, and therefore advance conservation tillage in intensive farming systems. [ABSTRACT FROM AUTHOR]

A laboratory rig was developed for a scale- and energy-controlled tender soil fragmentation test, which required multiple impacts and step-by-step decomposition of the soil structure on a macroscale. Soil sample size classes were scaled down by a factor of two, giving ranges of 128, 64, 32, 16, 8, 4, 2, 1, and 0.5 mm, respectively. These size classes were also used as control scales for respective fragmentation stages. Fragmentation tests were conducted to illustrate the possible influences from shape effects, falling weights, displacements, and fragmentation stages, and to investigate the relations among specific fragmentation energy, number of strokes per fragmentation stage, and fragmentation fractal dimension. Specific fragmentation energy was influenced by both the size and the shape of the soil samples. The cylindrical- and ball-shaped soil samples behaved similarly. Thus ball samples were used for a benchmarking test on soil structural stabilities. Subsequent fragmentation on 60- and 80-g ball samples with changed displacements from 5 to 45 cm yielded a decreased number of strokes from around 150 to 10. Whereas, their respective fragmentation fractal dimensions varied insignificantly, ranging from 1.52 to 1.64 for samples of 60-g mass and 1.55 to 1.72 for 80 g, values much smaller than previously reported. Fragmentation fractal dimension appeared to be a nominal index for remolded soils under laboratory impacting actions. There was a slight increase in specific fragmentation energy as the number of impacts increased. But this increase was aggravated for a single or only few impacts. Thus 20 to 40 strokes was the appropriate stroke number to finish one fragmentation stage. A five-stage fragmentation on a sample in the 32- to 64-mm size range yielded fragmentation fractal dimensions of 1.29, 1.52, 1.45 and 1.61, for the first four stages, respectively, whereas their specific fragmentation energies increased linearly.