Conservation Tillage Research Articles

A global insight on sensitivity of nitrate leaching to drainage in arable cropping systems

Nitrate (NO3–) leaching leads to widespread deterioration of water quality. NO3– leaching can be regulated by both biochemical and hydrological processes. However, the extent to which drainage accounts for the variation in NO3– leaching and the sensitivity of NO3– leaching to drainage remain unclear, particularly at the global scale. This raises uncertainties in prioritizing the regulation of hydrological (e.g., drainage) processes for reduced NO3– leaching. A global meta-analysis was conducted for arable cropping systems to test two hypotheses: (1) Global variations in NO3– leaching are explained more by drainage and associated influencing factors (e.g., water input); (2) NO3– leaching is more sensitive to the changes in drainage under conditions with lower risks of preferential flow. In this meta-analysis, the average NO3– leaching loss from arable cropping systems was 22.2 kg N ha−1 year−1. Water input, followed by N input, were the most influential in explaining global variations in NO3– leaching. Compared with NO3– concentration, drainage and associated influencing factors explained more of the global variations in NO3– leaching losses. NO3– leaching was more sensitive to drainage in soils with finer texture and higher soil organic carbon content, in regions with low to medium mean annual temperature (<15 ℃) and medium mean annual precipitation (600–1000 mm), where water input during the measurement period was low (<2 mm day−1), nitrogen fertilizer rates were high (>200 kg N ha−1), and where conservation tillage systems (no-tillage or non-inversion tillage) were adopted. Therefore, more attention should be given to avoiding excessive water application in soils characterized by low risk of preferential flow. Preferential flow reduces the chance for drainage water to interact with NO3– in the soil matrix, particularly in areas with high N inputs. While this study has successfully tested our hypotheses, it further highlights the importance of water input management for mitigating global NO3– leaching risks, particularly under environments and changing climate conditions more conducive to drainage events.

The Design and Experimental Validation of a Biomimetic Stubble-Cutting Device Inspired by a Leaf-Cutting Ant's Mandibles.

Under the conditions of conservation tillage, the existence of the root-soil complex greatly increases the resistance and energy consumption of stubble-cutting blades, especially in Northeast China. In this research, the corn root-soil complex in Northeast China was selected as the research object. Based on the multi-toothed structure of the leaf-cutting ant's mandibles and the unique bite mode of its mandibles on leaves, a gear-tooth, double-disk, bionic stubble-cutting device (BSCD) was developed by using a combination of power cutting and passive cutting. The effects of rotary speed, tillage depth, and forward speed on the torque and power of the BSCD were analyzed using orthogonal tests, and the results showed that all of the factors had a large influence on the torque and power, in the order of tillage depth > rotary speed > forward speed. The performance of the BSCD and the traditional power straight blade (TPSB) was explored using comparative tests. It was found that the optimal stubble-cutting rate of the BSCD was 97.4%. Compared with the TPSB, the torque of the BSCD was reduced by 15.2-16.4%, and the power was reduced by 9.2-11.3%. The excellent performance of the BSCD was due to the multi-toothed structure of the cutting edge and the cutting mode.

A trade-off between farm production and flood alleviation using land use tillage preferences as a natural flood management (NFM) strategy

Trade-off studies effectively compare rational decisions when choosing alternatives. This study utilizes a Bayesian belief network (BBN) model to analyse land use tillage practices for flood management, considering climate, soilscape, slope, and farming systems. The BBN comprises three sub-models using soil samples, farm surveys, synthetic datasets, and literature review data. In one scenario, conventional tillage on a 3° slope increased the net value of crop yield (50.85 %) and positive farm effects (49.64 %) but increased surface runoff (66.24 %) and reduced flood alleviation benefits (58.56 %). On the other hand, conservational tillage on a 3 ° slope yielded lower crop yield increase (14.11 %) and farm production effects (13.80 %) but reduced surface runoff (51.05 %) and increased flood alleviation benefits (45.06 %). Similarly, conventional tillage on a 12 ° slope showed similar crop yield and farm production effects, with slightly higher surface runoff (66.88 %) and reduced flood alleviation benefits (59.13 %). Conversely, adopting conservational tillage on a 12 slope resulted same extent of reduction in crop yield increase band (14.11 %) and farm production effects (13.80 %) but effectively reduced surface runoff (50.42 %) and improved flood alleviation benefits (44.49 %). Therefore, a trade-off between farm production and flood alleviation was identified when tillage preference was applied as a natural flood management strategy. Results showed this trend was particularly pronounced amongst soils on slopes. The model can help users in informed decisions on tillage for sustainable farming, with the potential for improvement through additional variables and farm-specific data.

Impact of agro-geotextiles on soil aggregation and organic carbon sequestration under a conservation-tilled maize-based cropping system in the Indian Himalayas

Although agro-geotextile (AGT) emplacement shows potential to mitigate soil loss and, thus, increase carbon sequestration, comprehensive information is scanty on the impact of using agro-geotextiles on soil organic carbon (SOC) sequestration, aggregate-associated C, and soil loss in the foothills of the Indian Himalayan Region. We evaluated the impacts of Arundo donax AGT in different configurations on SOC sequestration, aggregate stability, and carbon management index (CMI) since 2017 under maize-based cropping systems on a 4% land slope, where eight treatment procedures were adopted. The results revealed that A. donax placement at 0.5-m vertical-interval pea–wheat (M + AD10G0.5-P-W) treatment had ∼23% increase in SOC stock (27.87 Mg·ha−1) compared to the maize–wheat (M-W) system in the 0–30-cm soil layer. M + AD10G0.5-P-W and maize–pea–wheat treatments under bench terracing (M-P-W)BT had similar impacts on SOC stocks in that layer after 5 years of cropping. The total SOC values in bulk soils, macroaggregates, and microaggregates were ∼24, 20, and 31% higher, respectively, in plots under M + AD10G0.5-P-W treatment than M-W in the topsoil (0–5 cm). The inclusion of post-rainy season vegetable pea in the maize–wheat cropping system, along with AGT application and crop residue management, generated additional biomass and enhanced CMI by ∼60% in the plots under M + AD10G0.5-P-W treatment over M-W, although M + AD10G0.5-P-W and (M-P-W)BT had similar effects in the topsoil. In the 5–15-cm layer, there was no significant effect of soil conservation practices on CMI values. Under the M + AD10G0.5-P-W treatment, the annual mean soil loss decreased by ∼92% over M-W treatment. We observed that CMI, proportion of macroaggregates, aggregate-associated C, labile C, total SOC concentration (thus, SOC accumulation rate), and mean annual C input were strongly correlated with the mean annual soil loss from 2017 to 2021. The study revealed that the emplacement of an A. donax mat and incorporation of a legume in a cropping system (M-W), conservation tillage, and crop residue retention not only prevented soil loss but also enhanced C sequestration compared to farmers’ practice (M-W) in the Indian Himalayas. The significance of this study is soil conservation, recycling of residues and weeds, and climate change adaptation and mitigation, as well as increasing farmers’ income.

Exploring Sustainable Practices in Modern Agronomy and their Environmental Impact- A Review

The field of agronomy is undergoing a seismic shift towards sustainability, driven by an increasing understanding of the long-term benefits and a global urgency to act against climate change. It aims to explore the multifaceted realm of sustainable agronomy, scrutinizing its practices, benefits, challenges, and future prospects. It delve into the types of sustainable practices currently in use, such as crop rotation, organic farming, and conservation tillage, highlighting their positive impact on soil health, water quality, and biodiversity. We also offer a comparative analysis, contrasting these sustainable practices with conventional methods in terms of yield, economic benefits, and environmental impact. Also, dedicated to policy implications, discussing existing government policies that support sustainable practices and offering recommendations for further policy interventions. Case studies from India and abroad serve to demonstrate the practical application and success of these methods. The transition to sustainable agronomy is fraught with challenges. Technological needs, such as the requirement for advanced machinery and analytics tools, can be a hurdle, especially for small-scale farmers. Educational gaps also present a significant challenge, as current agronomy curricula in many parts of the world are not geared towards sustainable practices. Financial constraints, often exacerbated by inadequate support systems, add another layer of complexity to the transition. Despite these challenges, the review identifies multiple avenues for future research, including the development of cost-effective technologies, educational reforms, and alternative financing models to support farmers.

Soil Texture Mapping in Songnen Plain of China Using Sentinel-2 Imagery

Soil texture is a key physical property that affects the soil’s ability to retain moisture and nutrients. As a result, it is of extreme importance to conduct remote sensing monitoring of soil texture. Songnen Plain is located in the black soil belt of Northeast China. The development of satellite imagery in remote sensing technology enables the rapid monitoring of large areas. This study aimed to map the surface soil texture of cultivated land in Songnen Plain using Sentinel-2 images and Random Forest (RF) algorithm. We conducted this study by collecting 354 topsoil (0–20 cm) samples in Songnen Plain and evaluating the effectiveness of the bands and spectral indices of Sentinel-2 images and RF algorithm in predicting soil texture (sand, silt, and clay fractions). The results demonstrated that the 16 covariates were moderately and highly correlated with soil texture. And, Band11 of Sentinel-2 images could be used as the corresponding band of soil texture. For sand fraction, the Sentinel-2 images and RF algorithm’s Coefficient of Determination (R2) and Root Mean Square Error (RMSE) were 0.77 and 10.48%, respectively, and for silt fraction, they were 0.75 and 9.38%. Sand fraction decreased from southwest to northeast in Songnen Plain, while silt and clay fractions increased. We found that the Songnen Plain was affected by water erosion and wind erosion, in the northeast and southwest, respectively, providing reference for the implementation of Conservation Tillage policies. The outcome of the study can provide reference for future soil texture mapping with a high resolution.

Effects of long-term conservation tillage on N2 and N2O emission rates and N2O emission microbial pathways in Mollisols

Conservation tillage is widely used in farmland management for soil carbon sequestration, but it can also lead to potential emissions of nitrous oxide (N2O). Therefore, our study is aimed to investigate the effects of 15 years of no-tillage combined with four straw mulching levels of 0 % (NT0), 33 % (NT33), 67 % (NT67), and 100 % (NT100) compared to ridge tillage (RT) on the rates of N2O and N2 emissions and the respective contributions of four microbial pathways to N2O emissions. The incubation experiments were conducted at two different moisture levels (55 % and 100 % WFPS) by using dicyandiamide inhibition and 15N-labeling techniques. Soil samples were collected from the 0–20 cm and 20–40 cm soil depths across three maize growth stages: seedling, jointing, and maturity. Our results showed that conservation tillage significantly decreased the N2O + N2 emission at 55 % WFPS, but it has a reverse influence in N2O + N2 emission at 100 % WFPS. The proportion of N2O in gaseous N loss were higher at 100 % WFPS than at 55 % WFPS. Among the four microbial pathways for N2O emissions, autotrophic nitrification was the dominant pathway 55 %WFPS. The contribution of autotrophic nitrification remarkably decreased, co-denitrification and denitrification increased at 100 %WFPS. Overall, at 100 % WFPS, N2O emissions from all major microbial pathways were positively correlated with GWC, temperature, TC, TN, NH4+-N, and NO3−-N, but negatively correlated with soil pH and C/N ratios. Our results suggest that long-term conservation tillage increases N2O and N2 emissions from the soil under water-saturated conditions by regulating soil nutrient levels, soil moisture, and microbial pathways. Therefore, we should consider the impact of conservation tillage on N2O emission risk when we attach importance to the role of conservation tillage in improving soil quality and increasing crop yields.

Effects of Biochar and Cattle Manure under Different Tillage Management on Soil Properties and Crop Growth in Croatia

The negative environmental impact of conventional agriculture threatens agroecosystem stability and food security. Therefore, searching for optimal soil management practices is crucial for maintaining and improving soil functions. This work aims to determine the impact of conventional and conservation tillage on Stagnosols in a semi-humid environment in Marija Magdalena (Croatia) during 2021 and 2022. Under each tillage treatment, subplots were biochar, cattle manure, and control (split-plot design). The conservation tillage exhibits lower compaction in addition to conventional tillage. In 2021, at 0–15 cm and 15–30 cm depths, control plots had the highest bulk density (BD), while biochar plots had the lowest. In 2022, biochar and manure treatments under conventional tillage had significantly higher BD than those under conservation tillage. Penetration resistance did not exceed 2 MPa in all treatments. Soil water content was high in conservation treatments at 0–15 cm. Water-stable aggregates were higher in biochar and manure plots under both tillage treatments. Maize yield was higher in conservation treatments in 2021 and in conventional during 2022. Manure and biochar in the conventional system showed a better impact on grain yields than under conservation. Conservation tillage in rain-fed farming maintains crop yields and reduces soil compaction.

Testing for complementarity between the use of continuous no-till and cover crops: An application of entropy approach

The carbon sequestration and overall crop production sustainability benefits of no-till (NT) farming are fully realized only when NT is used continuously over several years. Research shows that most U.S. farmers do not use the practice continuously. One of the commonly suggested reasons for intermittent tillage is the risk of a significant yield penalty during the first several years after converting to continuous no-till (CNT). Agronomic research suggests that continuous cover crops (CCR) can be both an economical and biological answer to the risk of yield reduction associated with the use of CNT, as CCR accelerates the processes of converting and storing nitrogen in the soil and improves soil structure and water infiltration. However, whether farmers consider the complementary benefits of CNT and CCR is largely unknown. The objective of this study is to test the complementarity between the uses of the two conservation practices in the State of Indiana, U.S. We combine Quadratic Programming and Entropy approaches to estimate 1st-order Markov transition matrices for tillage and cover crops dynamic models, respectively. Then, we apply Bayes' theory to test the complementarity. The data used for the analysis come from the Conservation Tillage Information Center and Indiana Tillage and Cover Crops Transect, 1992–2019. The findings show that there is no evidence supporting complementarity between the use of CNT and CCR in Indiana. The results also show that the use of CCR in the State is growing steadily at a rate of approximately 30% during 2011–2015 and then stabilize during 2016–2019, whereas the share of land allocated to CNT remains flat in the same period. In addition to being the first formal test of the complementarity between the uses of the two sustainable crop production practices, the novelty of our contribution relates to the econometric methodology and the data. We introduce an approach for estimating dynamic models of farmers' yearly choices and demonstrate the possibility of testing for complementarity between the choices with very limited – aggregated and missing – data.

Effects of Conservation Tillage on Herbicide Residues in Maize Field Soil

It is well known that conservation tillage can improve soil quality, such as soil organic matters. However, limited information on the conservation tillage impacts on pesticides has been reported, which is important to food security. To explore the specific effects of conservation tillage on herbicide residues in soils, parallel soil samples from seven sites under traditional tillage and conservation tillage were collected, respectively, in Jilin Province, Northeast China. The soil properties and characteristics of three herbicides(acetochlor, atrazine, and MCPA-Na) were measured. The results showed that conservation tillage significantly increased total organic carbon(TOC) content, soil water content, and the average particle size of soil aggregates[(2.1±0.1)%, (19.1±1.2)%, and (82.2±3.0) μm increased to(2.9±0.3)%, (22.3±1.5)%, and (97.2±4.2) μm, respectively]. The results also showed that different herbicides were correlated with different soil properties. For example, TOC content and soil water content were positively correlated with atrazine, whereas micro-aggregate content was negatively correlated with acetochlor. Therefore, the effects of conservation tillage on the three herbicide residues were different. For instance, conservation tillage significantly increased the residual amount of atrazine[from(3.8±0.3) ng·g-1 to (17.7±3.0) ng·g-1] in the Dongfeng site by increasing TOC content, whereas it significantly reduced the residual amount of acetochlor[from (50.6±10.3) ng·g-1 to (9.2±2.5) ng·g-1] in the Dehui site by increasing the average particle size of soil aggregates. Generally, this study suggests conservation tillage indeed affected herbicide residues in soils by affecting soil properties. However, the influence of conservation tillage on herbicide residue was dependent on the types of herbicides due to the complex effects of different soil properties on herbicide migration and degradation.

Tillage systems affect soil nitrogen availability and interact growth parameters of different faba bean cultivars

Abstract. Al-Enezy AFM, Zaidan BA, Almehemdi AF, Hussein AA, Salih MAA. 2023. Tillage systems affect soil nitrogen availability and interact growth parameters of different faba bean cultivars. Biodiversitas 24: 5558-5564. A field trial was conducted during the winter season of 2021-2022 in one of the agricultural lands of Hamid Shaban village, which belongs to Abu Ghraib District of Baghdad Province (33°17'51.3"N, 44°04'55.0"E). The aim of the experiment was to investigate nitrogen availability in two different tillage systems and the growth characteristics of six broad bean varieties on clay-loamy soils. The field trial was triplicated using the Randomized Complete Block (RCBD) method. The first factor was the six broad bean varieties (Turkish, Dutch, Italian, Spanish, American and local), the second factor was the cultivation system Conservation Tiltage (no-till) and the traditional cultivation with a mouldboard plow. The results showed that the availability of nitrogen in the soil in the traditional tillage system corresponds to the superior to conservative tillage systems. Where this gives an average available nitrogen concentration of 23.3 mg kg-1, an increase of 21 in relation to conservation tillage, which resulted in an average concentration of available nitrogen of 19.1 mg kg-1. In addition, all the growth characteristics of the plants favored the traditional agricultural system. In the variety comparison, the Italian variety was characterized by the highest nitrogen content available in the soil of 26.10 mg kg-1 as well as the highest values ??of plant growth properties among the six varieties.

Effects of Different Tillage and Fertilization Methods on the Yield and Nitrogen Leaching of Fragrant Rice

Conservation tillage and deep-side fertilization both hold the potential to reduce nitrogen leaching and improve grain yield and nitrogen use efficiency in fragrant rice cultivation practices. However, the combined impact of different tillage practices with deep-side fertilization on nitrogen leaching remains uncertain. Therefore, this study conducted on-site experiments for four rice-growing seasons in both early and late seasons in 2018 and 2019 using the fragrant rice varieties “Meixiangzhan 2” (MX) and “Xiangyaxiangzhan” (XY). The four experimental treatments included the following: conventional tillage with regular fertilization (T1), conventional tillage with simultaneous deep fertilization (T2), reduced tillage with simultaneous deep fertilization (T3), and no-tillage with simultaneous deep fertilization (T4). Our results indicate that the T4 treatment exhibited higher nitrogen leaching rates and potential nitrogen losses throughout the entire rice growth cycle, with a 4.51% increase in total mineral nitrogen leaching (TMNL) and a 1.86% increase in potential nitrogen leaching compared to T1 treatment. In contrast, the T2 treatment demonstrated the lowest nitrogen leaching rate, resulting in a 6.01% reduction in TMNL and a 9.57% decrease in potential nitrogen leaching compared to T1, demonstrating the most optimal performance. It is important to note that a reduction in nitrogen leaching does not directly translate into an increase in rice yield. Our study involved the cultivation of two fragrant rice varieties, ‘Meixiangzhan2’ (MX) and ‘Xiangyaxiangzhan’ (XY), and the results revealed some interesting insights. For MX, the T1 treatment resulted in lower daily grain outputs compared to the other treatments, with disparities ranging from 5.35% to 9.94%. Similarly, for XY, the T1 treatment yielded significantly lower daily grain outputs compared to the other treatments, with discrepancies ranging from 6.26% to 10.81% during the late season of 2019. Therefore, this study suggests that conventional tillage combined with deep fertilizer application can be considered as an effective agricultural strategy to reduce nitrogen leaching and enhance fragrant rice yields.

Effect of long-term conservation tillage management on microbial diversity under Mediterranean rainfed conditions

Conservation Agriculture has been the subject of numerous studies for decades. However, its impact on the soil microbial community has often been overlooked. Recent studies have shed light on the changes in soil bacterial composition resulting from modifications in tillage practices, particularly when compared to conventional tillage methods. However, there is a lack of soil microbial community analysis conducted under conservation tillage and rainfed conditions in the Mediterranean basin. A metataxonomic approach was employed to assess the influence of 19 years (2004–2022) of minimum tillage (MT) and no-till (NT) practices, along with crop rotation, on the soil bacterial community at upper layers (15 cm depth). This field study involved three different seasonal moments throughout the year. Results revealed that both sampling time and tillage management significantly influenced the structure of the bacterial community, whereas no effect was observed due to the crop. May showed a higher taxonomic diversity than July and December, showing differences in some o fthe most abundant phyla, such as Actinobacteria, Firmicutes and Proteobacteria. On the other hand, the long-term application of NT was found to lead to a significant decrease in bacterial diversity, with lower abundances of the phyla Chloroflexi, Gemmatimonadetes, and Armatimonadota, as well as an increase in k-strategist bacteria compared to MT. However, no significant effect on alpha diversity was observed as a result of tillage. no variations in phyla composition were observed attributable to crop, as the primary distinctions were identified among legume crops, which were associated with different sampling times. Therefore, our conclusion is that over this period, NT did not promote microbial diversity in the upper soil layers, despite notable shifts in bacterial composition occurring across seasonal time points in both tillage management systems.

Long-term conservation tillage improves soil stoichiometry balance and crop productivity based on a 17-year experiment in a semi-arid area of northern China

Although conservation tillage has been widely implemented to address the challenge to improve crop yield and soil quality with fewer environmental costs, its long-term effects on crop yields and soil stoichiometry balance remain uncertain. Here, four different long-term (17-year) tillage practices (conventional tillage (CT), deep scarification (DS), no tillage (NT), and ridge tillage (RT)) were conducted in northern China to evaluate their effects on crop yield, soil nutrients, C sequestration, and soil stoichiometry. The conservation tillage (DS, NT, and RT) increased the recent 5-year average yields by 12.2 %–20.1 % compared with CT, respectively. RT showed the highest C sequestration potential of 10.0 t/ha, followed by DS and NT (6.0 t/ha and 4.4 t/ha, respectively). The DS, NT, and RT enhanced soil available N and K with the best effect for NT, but DS reduced soil total and available P. The conservation tillage significantly increased the C:N, C:P, C:K, and N:P ratios, indicating it sustained soil balanced stoichiometry. Correlation analysis indicated crop yield was closely related to soil C:N, C:P, C:K, and N:P. The structural equation model revealed that the C, N, and P affected C:N and C:P ratios, thus improving crop yield under long-term conservation tillage. In summary, long-term conservation tillage improves soil stoichiometry balance and thus crop yields with great C sequestration potential to achieve sustainable agricultural management in rain-fed farmland.

Conservation tillage and fertiliser management strategies impact on basmati rice (Oryza sativa L): crop performance, crop water productivity, nutrient uptake and fertility status of the soil under rice-wheat cropping system.

The sustainability of paddy production systems in South Asia has recently been affected by a decline in soil health and excessive water usage. As a response to the global energy crisis, escalating costs of synthetic fertilisers, and growing environmental concerns, the utilization of organic plant-nutrient sources has gained considerable attention. Emerging adaptation technologies, including conservation tillage and innovative approaches to fertilizer management, present practical choices that can significantly contribute to the long-term preservation of soil fertility. The two year-long field experiment was completed in sandy loam soil during rainy (Kharif) seasons in 2019 and 2020 at the crop research centre farm of Sardar Vallabhbhai Patel University of Agricultural & Technology, Meerut, Uttar Pradesh to analyze the impacts of different tillage establishment of the crop and its methodologies as well as integrated nutritional management approaches on rice growth, yield, productivity of water, nutrient uptake, and fertility status of soil under a rice-wheat rotation system. The experiment was set up in a factorial randomized block design and replicated three times in a semi-arid subtropical environment. The conventionally transplanted rice puddled (CT-TPR) grew substantially better taller plants, and higher dry matter buildup leads to increased yields than transplanted rice under raised wide bed (WBed-TPR). WBed-TPR plots had more tillers, LAI, CGR, RGR, and yield characteristics of the rice in two year study. CT-TPR increased grain yield by 4.39 and 4.03% over WBed-TPR in 2019 and 2020, while WBed-TPR produced the highest water productivity (0.44 kg m-3) than CT-TPR, respectively. The 100% RDF+ ZnSO4 25 kg ha-1 + FYM (5 t ha-1) + PSB (5 kg ha-1) + Azotobacter 20 kg ha-1 (N6) treatment outperformed the other fertiliser management practices in terms of crop growth parameters, yields of grain (4,903 and 5,018 kgha-1), nutrient uptake and NPK availability, organic soil carbon. Among the fertilizer management practices, with the direct applications of the recommended dose of fertilizer (RDF), farm yard manure (FYM), phosphate solubilizing bacteria (PSB), Azatobactor and zinc worked synergistically and increased grain yields by 53.4, 51.3, 47.9 and 46.2% over their respective control treatment. To enhance rice productivity and promote soil health, the study suggests that adopting conservation tillage-based establishment practices and implementing effective fertilizer management techniques could serve as practical alternatives. It is concluded that the rice yield was improved by the inclusive use of inorganic fertiliser and organic manure (FYM). Additionally, the study observed that the combination of conventional puddled transplanted rice (CT-TPR) and N6 nitrogen application resulted in enhanced rice crop productivity and improved soil health.

Design and Experimental Analysis of Straw Suction Unit on Straw Cover Weight Detection Machine

In response to the issues of high cost, limited detection accuracy, and significant measurement errors inherent in conventional manual techniques used to measure straw cover weight under the conservation tillage method, a dedicated straw cover weight detection machine was developed in the current study. This machine included a critical straw suction device that utilizes negative pressure to collect straw within a defined area. The efficiency of straw collection is affected by suction chamber structural parameters and transport pressure. With crushed corn straw as the research subject, the theoretical calculation of straw suspension velocity was used to determine the wind duct diameter, perform the initial design of the suction chamber structure, and select the appropriate fan. After conducting preliminary experiments, single-factor optimization tests, and orthogonal rotation experiments, we analyzed the flow field distribution patterns and identified the critical parameters for the straw cover weight suction unit. We found that the fan should operate at a speed of 2900 r/min, the diameter of the straw outlet should be 200 mm, the vertical height of the suction chamber should be 536 mm, and the bottom diameter of the suction chamber should be 800 mm. The optimization results were validated through simulation tests and bench tests, yielding an average near-ground airflow velocity of vj = 9.03 m/s and an average outlet airflow velocity of vo = 34.27 m/s, meeting the basic requirements of the suction unit. This study could provide a new approach and technical support for the automated detection of straw cover weight in conservation tillage areas.

The importance of shrubland and local agroecological practices for pumpkin production in sub-Saharan smallholdings

Land-use and local field management affect pollinators, pest damage and ultimately crop yields. Agroecology is implemented as a sustainable alternative to conventional agricultural practices, but little is known about its potential for pollination and pest management. Sub-Saharan Africa is underrepresented in studies investigating the relative importance of pests and pollinators for crop productivity and how this might be influenced by surrounding landscapes or agroecological practices. In Malawi, we selected 24 smallholder farms differing in landscape-scale shrubland cover, implementation of manual pest removal as an indicator of an agroecological pest management practice, and the number of agroecological soil practices employed at the household level, such as mulching, intercropping and soil conservation tillage. We established pumpkin plots and assessed the abundance and richness of flower visitors and damage of flowers (florivory) caused by pest herbivores on flowers. Using a full-factorial hand pollination and exclusion experiment on each plot, we investigated the relative contribution of pollination and florivory to pumpkin yield. Increasing shrubland cover decreased honeybee abundance but increased the abundance and richness of non-honeybee visitors. Manual removal of herbivores considered to be pests reduced flower visitors, whereas more agroecological soil management practices increased flower visitors. Neither shrubland cover nor agroecological management affected florivory. Pollinator limitation, but not florivory, constrained pumpkin fruit set, and increasing visitor richness decreased the relative differences between hand- and animal-pollinated flowers. We recommend improved protection of shrubland habitats and increasing agroecological soil practices to promote pollinator richness on smallholder farms.

Effects of Subsoiling with Different Wing Mounting Heights on Soil Water Infiltration Using HYDRUS-2D Simulations

Subsoiling is an essential practice in conservation tillage technology. The amount of disturbed soil at various depths resulting from subsoilers with different parameters has an important effect on soil properties (e.g., bulk density and water infiltration). The information regarding the effects of subsoiling on the characteristics of soil water infiltration is essential for the design of subsoiling tools. In this study, the effects of the wing mounting height (h) (75–155 mm) of the subsoiler on soil disturbance and soil water infiltration were modelled using HYDRUS-2D and validated using field experiments. Results showed that reducing h values resulted in larger soil disturbance area ratios, soil water infiltration rates (f(t)), distances of vertical wetting front movement (DVWs), accumulative infiltrations (AINs), and soil moisture contents at depths of 10–30 cm. The relationships among characteristics of soil water infiltration, h and time (t), were developed. The stable infiltration rates (fs) varied quadratically with h and the corresponding coefficient of determination (R2) was 0.9869. The Horton model is more suitable for describing the relationship between f(t) and t under the tested soil conditions, as compared with the Kostiakov and Philip models. According to the results of soil water content at different depths from the HYDRUS simulations and field experiments, the developed soil water infiltration model had a good accuracy, as indicated by RMSEs of &lt;0.05, R2 values of &gt;0.95, and mean relative errors of &lt;12%. The Above results indicated that increasing the hardpan disturbance by optimizing wing parameters of the subsoiler could improve soil water infiltration characteristics.

Optimizing Cotton-Wheat System Productivity Through Resource Conserving Techniques

ABSTRACT Cotton-wheat cropping system contributes significantly to Pakistan’s food security and economy. However, the system productivity is low because of soil degrading tillage, irrational use of irrigation, and potassium which delay cotton maturity and affect succeeding wheat crop. Conservation tillage (MT) with appropriate irrigation and potassium may improve the system’s productivity and stability. Experiments were conducted at Gomal University, Pakistan. Treatments included tillage (conventional (CT) and conservation tillage (MT)) and three irrigation intervals viz. 5, 4, and 3 weeks for cotton in first year, while in second year tillage was same and best irrigation interval observed in first year was kept constant. In second year besides tillage, potassium (0, 50, 100, 150, 200, and 250 kg K ha−1) was included in cotton. For succeeding wheat, treatments were tillage (MT & CT) and six irrigations applied at crown root initiation, tillering, jointing, booting, 50% spike emergence, milk and dough stage. Results revealed that MT was better than CT regarding yield and net economic return. Five-week irrigation interval increased yield, improved fiber quality, and caused earlier cotton maturity. 150 kg K ha−1 produced higher net return and benefit–cost ratio (BCR) for cotton under MT than CT. Wheat grown with MT produced higher yield, net return, and BCR when irrigated 4 times at jointing, booting, 50% spike emergence, milk and dough stage. MT accumulated more soil organic matter and total soil N than CT. The results suggest that MT with appropriate irrigation and potassium can improve cotton-wheat system productivity and economics besides conservation of resources.

Soil sampling depth effect on critical soil test values of phosphorus for conservation agriculture

AbstractThe critical soil test value (CSTV) of phosphorus (P) is the threshold where it is possible to obtain 95–100% of the maximum crop yield. Although the P buildup in the topsoil of conservation tillage may affect this threshold, the effect of soil sampling depth on CSTV value has not been determined for conservation tillage in the southern United States. The objective of this study was to evaluate CSTV of P using different soil layers from two long‐term experiments managed under varying P rates, planted to corn (Zea mays L.)/soybean [Glycine max (L.) Merr.] rotation under minimum tillage (Tidewater) or no‐tillage (Piedmont) in North Carolina. Soil samples were taken from depths of 0–2, 2–4, 4–8, and 8–12 inches. The CSTV for different soil layers was calculated using a quadratic‐plateau model with Mehlich‐3 P and relative yield of soybean and corn (2021–2022). The CSTV decreased as the soil sampling depth increased. The CSTV of P at the Tidewater site was 128, 111, 86, and 74 lb ac−1, and at the Piedmont site was 28, 20, 16, and 15 lb ac−1 for the 0–2, 0–4, 0–8, and 0–12 inches soil layers, respectively. Using multiple sampling layers or deeper layers did not improve the quality of CSTV measurement. The current sampling depths used in North Carolina are appropriate for minimum tillage (0–8 inches) and no tillage (0–4 inches), as similar quality models were obtained using either soil layers in both sites. However, it is important to be cautious when changing the sampling depth, as this affects the CSTV value.