No-till Research Articles

Assessing Weed Canopy Cover in No-Till and Conventional Tillage Plots in Winter Wheat Production Using Drone Data

Weed canopy cover assessment, particularly using drone-acquired data, plays a vital role in precision agriculture by providing accurate, timely, and spatially detailed information, enhancing weed management decision-making in response to environmental and management variables. Despite the significance of this approach, few studies have investigated weed canopy cover through drone-based imagery. This study aimed to fill this gap by evaluating the effects of conventional tillage (CT) and no-till (NT) practices on weed canopy cover in a winter wheat field over two growing seasons. Results indicated that in the 2022–2023 season, weed populations were similar between tillage systems, with a high mean weed cover of 1.448 cm2 ± 0.241 in CT plots. In contrast, during the 2023–2024 season, NT plots exhibited a substantially higher mean weed cover (1.784 cm2 ± 0.167), with a significant overall variation (p < 0.05) in weed distribution between CT and NT plots. These differences suggest that, while CT practices initially mask weed emergence by burying seeds and disrupting root systems, NT practices encourage greater weed establishment over time by leaving seeds near the soil surface. These findings provide valuable insights for optimizing weed management practices, emphasizing the importance of comprehensive approaches to improve weed control and overall crop productivity.

Corn grain yield, residue production, and nutrient concentration and extraction is affected by different residue incorporation rates in two biannual crop rotations

Abstract Conservation practices in agriculture using crop rotations and residue management benefit the productivity; these can vary depending on climate and soil conditions, crops, and amount of incorporated residue. The present study evaluated the effect of two biannual rotations; canola (Brassica napus L.) – corn (Zea mays L.) and bean (Phaseolus vulgaris L.) – corn rotations with four residue incorporation rates (0%, 50%, 100%, and 200%) of the preceding crop on corn grain yield, residue production, and nutrient concentration and extraction after two rotation cycles in a volcanic soil of moderate depth in south-central Chile. Grain yield varied between 17.04 and 17.40 Mg/ha, residue production between 16.41 and 16.50 Mg/ha. The preceding crop affected concentration and extraction of some nutrients in both grain and residue. The residue rate affected both concentration and extraction of some nutrients only in the grain. The Ca distribution to the corn grain was negatively affected by both the preceding bean crop and increasing residue incorporation rate. The ranking of total macronutrient extraction in the corn crop was K > N > Ca > P > Mg > S. The extraction means ranged from 320 to 326, 56.0 to 57.1, 365 to 374, 86.5 to 99.3, 39.4 to 42.4, and 22.6 to 23.7 kg/ha, whereas grain nutrient distribution coefficients ranged from 64.5 to 66.8, 90.1 to 90.9, 23.1 to 23.7, 1.3 to 2.0, 50.8 to 57.5, and 60.3 to 60.6 for N, P, K, Ca, Mg and S, respectively.

Climate Smart Agriculture: Innovating Sustainable Practices for a Changing Climate

Climate Smart Agriculture (CSA) is a strategy aimed at lowering greenhouse gas emissions, strengthen climate change resilience, raising crop production and incomes significantly. In a variety of agro-ecological zones, the implementation of climate smart agriculture methods has significantly improved the availability of food, adaptability to fluctuations in the climate, and emissions reduction. One of the key benefits of CSA is its ability to improve agricultural productivity and stabilize food security, particularly for small-scale farmers in developing nations who are most vulnerable to climate change. By integrating sustainable techniques such as conservation agriculture, crop diversification, and agroforestry, CSA helps ensure stable yields, even amid erratic weather patterns. Enhanced soil fertility, enhanced irrigation practices and the use of varieties of crops that are climate resilient all contribute to sustained productivity, mitigating the risks of crop failure and food shortages. CSA also strengthens agricultural systems' resilience to climate impacts by promoting practices like zero tillage, residue management, and efficient irrigation, which improve soil health and water retention, making crops more resistant to droughts and floods. In addition to boosting resilience, CSA contributes to climate change mitigation by reducing agriculture's carbon footprint. Precision farming, organic agriculture, and other low-emission practices help curb greenhouse gas emissions from farming activities. Mobile technology is also emerging as a key driver of CSA by providing real-time information, decision-making support, and access to essential resources, further enhancing the adaptability and sustainability of farming systems. The significance of CSA as a strategic solution to the threats that climate change poses to food security and agricultural sustainability is being more widely acknowledged by governments. As a result, numerous initiatives have been launched at national, regional, and international levels to encourage the widespread adoption of CSA practices. In order to achieve sustainable agricultural development and ensure food security in the face of climate change, CSA must be scaled up around the world.

Rice residue management alternatives and nitrogen optimization: impact on wheat productivity, microbial dynamics, and enzymatic activities

In response to the degraded soil health and lack of improvement in the yield of rice–wheat cropping systems in South Asia’s Indo-Gangetic Plains, an experiment was formulated in a split-plot design. Four rice residue management practices were the primary factor, alongside two nitrogen levels (150 and 180 kg/ha) and two nitrogen split levels (two and three splits) as sub-treatments. The findings revealed a notable increase in soil organic carbon (SOC), microbial count, and enzymatic activity in plots subjected to conservation tillage and residue treatment compared to those in plots subjected to partial residue (anchored stubbles) and conventional methods (residue incorporated with chopping). The collective analysis demonstrated a significant influence of rice residue management practices and nitrogen application levels on wheat yield attributes and productivity. Specifically, zero tillage with full residue (unchopped) in wheat exhibited a 5.23% increase in grain yield compared to conventional tillage with full residue (chopped), concurrently boosting the soil microbial count by 19.80–25%, the diazotrophic count by 29.43–31.6%, and the actinomycete count by 20.15–32.99% compared with conventional tillage. Moreover, applying nitrogen in three splits (at sowing, before the 1st irrigation, and after the 1st irrigation) led to a 6.25% increase in grain yield than that in two splits (at sowing and after the 1st irrigation), significantly impacting wheat productivity in the soil. Furthermore, the zero tillage-happy seeder with full residue elevated dehydrogenase activity from 77.94 to 88.32 μg TPF/g soil/24 h during the study year, surpassing that in the conventional plot. This increase in enzymatic activity was paralleled by a robust positive correlation between the microbial population and enzymatic activity across various residue retention practices. In conclusion, the results underscore the efficacy of crop residue retention following conservation tillage, in tandem with nitrogen optimization and scheduling, in enhancing wheat yield within the rice–wheat cropping system.

ASSESSMENT OF SMALL HOLDERS FARMERS' ADOPTION OF CLIMATE-SMART AGRICULTURE PRACTICES IN BORNO STATE, NIGERIA

The study assessed smallholder farmers’ adoption of Climate-Smart Agriculture practices in Borno State, Nigeria. Identified socio-economic characteristics of the respondents, assessed the respondents’ adoption of climate-smart agriculture practices and investigated the constraint by respondents in adopting climate-smart agriculture practices. Both primary and secondary sources were used. Multi-stage sampling procedure was employed to select 200 respondents as the sample size. Descriptive statistics such as frequency, percentages, mean, standard deviation and likert type scale were used. The findings indicated that, majority (67.5%) of the respondents were within the prime working age of 20-49 years with a mean age of 43 years. Majority (75.5%) were male, 63.5% married with 43.0% had 7-9 persons per household. However, more than half (56%) of the respondents had no formal education, and 56% earn less than 50,000 Naira annually. The study also found that 58% had more than 10 years of farming experience, but only 30% were members of association. Conservation agriculture practices such as reduced tillage, crop residue management, and crop rotation/intercropping were rated 1st with the highest (x = 4.29) implying strong agreement to adoption of conservation agriculture practices. The climate smart agricultural practices highly adopted by the respondents include; water retention and erosion control technique (89%) and efficient fertilizer application technique (79.5%), moderately adopted practices; home garden (63%) and compost making/green manuring (58%), whereas least adopted practices; early warning system (20.0%) and use of more efficient cooking stove (17%). The most severe constraint identified include lack of awareness and limited information about climate smart agriculture practices (x=1.87), as well as limited access to credit (x=1.80). High cost of labor for climate smart agriculture and policy inconsistencies (x=1.32, 1.44) were identified as not severe constraint compared to others. The study recommended that Extension agents and Research institute should create more awareness on impact of adopting Climate Smart Agriculture (CSA) practices and improve easy accessibility to weather and climate information through provision of mobile-based platforms or community radio broadcasts that deliver timely and relevant information.

Optimization of Briquetting Process Parameters for Rice Straw Biofuels

The optimization of briquetting process parameters for producing biofuels from rice straw, a widely available agricultural waste. By systematically varying key parameters such as pressure, temperature, and moisture content, we aimed to enhance the physical and thermal properties of the briquettes. Through experimental design and statistical analysis, we identified optimal conditions to maximize briquette density and calorific value while minimizing ash content. The findings show that optimized briquetting greatly enhances the efficiency and potential of rice straw as a renewable energy source, providing a sustainable alternative to traditional fuels. This research contributes to advancing biofuel production technologies and promoting the utilization of agricultural waste for energy generation. Briquetting technology has great potential to transform waste biomass in affordable, effective and environmentally safe, high-quality solid fuel for households and industry use. This study focuses on optimizing the briquetting process for rice straw to enhance its quality as a biofuel. Key parameters, including compaction pressure, moisture content, binding agent type, and particle size, were systematically varied to improve density, durability, hardness, calorific value, and reduce ash content. Results indicate significant improvements in briquette performance, with calorific values increasing to 17.5 MJ/kg and ash content reducing to 4%. Optimized briquettes offer enhanced mechanical strength and combustion efficiency, positioning rice straw briquettes as a viable, eco-friendly alternative to traditional fossil fuels, contributing to sustainable energy and agricultural residue management.

Soil metagenomics reveals reduced tillage improves soil functional profiles of carbon, nitrogen, and phosphorus cycling in bulk and rhizosphere soils

Conservation tillage practices (CAT) are known to benefit soil health and soil ecosystem functions relative to conventional tillage (CVT); however, much uncertainty remains concerning microbial functional traits and their subsequent effects on soil nutrients under different tillage practices. We analyzed the functional profiles of the C, N, and P cycles in response to CAT of no-tillage (NT), reduced tillage (RT), and CVT of moldboard plowing (MP) in bulk and rhizosphere soils using shotgun sequencing. CAT induced distinct microbial functional patterns relative to CVT, and these differences were generally more evident in rhizosphere soils than in bulk soils. CAT promotes multiple metabolic pathways such as C and N decomposition, fermentation, CO oxidation, N fixation, nitrate reduction and inorganic-P and organic-P transformations in bulk and/or rhizosphere soils. Variations in these metabolic pathways were mainly driven by Bradyrhizobium, Mesorhizobium, Nitrososphaera, Phenylobacterium, Rhizobium which are affiliated with Proteobacteria, Actinobacteria, Acidobacteria, Bacteroidota and Thaumarchaeota. Furthermore, 24 high-quality metagenome-assembled genomes (MAGs) were reconstructed, of which three novel MAGs (TL100, TL46, and TL57) harbored functional genes regulating all metabolic pathways. In particular, NT-enriched MAGs (such as Sphingomonas) promote fermentation, resulting in the reduction of soil total carbon (TC) relative to MP in bulk soils. RT retained the contents of soil TC and total nitrogen (TN) well and up-regulated the phoR gene carried by Streptomyces, which promoted the regulation of P-starvation concomitantly with the increase in the contents of total phosphorous (TP) and available phosphorous (AP) in bulk soil. Additionally, assimilatory nitrate reduction coupled with organic-P mineralization was facilitated by CAT in rhizosphere soil, leading to the mitigation of N loss and the activation of soil organic-P for crop uptake. Overall, our results revealed that CAT significantly accelerated multiple metabolic potentials, and RT could sustain soil nutrient contents better than NT.

Optimized Polyhydroxybutyrate Production by Neobacillus niacini GS1 Utilizing Corn Flour, Wheat Bran, and Peptone: A Sustainable Approach

Plastic pollution is a pressing environmental challenge, necessitating the development of biodegradable alternatives like polyhydroxybutyrate (PHB). This study focuses on optimizing PHB production by Neobacillus niacini GS1, a bacterium isolated from a municipal dumping site. By utilizing agricultural residues such as corn flour, wheat bran, and peptone as substrates, we aimed to establish an eco-friendly method for biopolymer production, contributing to sustainable agricultural residue management and bioplastic innovation. The bacterium was identified using morphological, biochemical, and molecular techniques. The optimization process involved adjusting variables such as inoculum age, inoculum size, incubation time, agitation rate, incubation temperature, pH of the medium, carbon sources, and nitrogen sources. Response surface methodology (RSM) was employed to identify optimal conditions, with the highest PHB yield of 61.1% achieved under specific conditions: 37 °C, pH 7, and an agitation rate of 150 rpm. These findings underscore the potential of Neobacillus niacini GS1 in converting agro-industrial residues into valuable biopolymers, promoting sustainable bioplastic production, and advancing agricultural residue valorization efforts through the use of eco-friendly materials.

Microbial Decomposer for Crop Residue Management in Rice-Wheat Cropping System.

Crop residue management is vital in the Rice-Wheat cropping system, influencing soil health and crop productivity. This study examined the effects of organic and inorganic fertilizers and microbial decomposers on rice growth and yield. We evaluated seven treatments: 100% recommended dose fertilizer (RDF); 50% residue + 50% RDF; 50% residue + 50% RDF + Pusa decomposer; 50% residue + 50% Green Manuring (GM)/Green Leaf Manuring (GLM); 50% residue + 50% GM/GLM + Pusa decomposer; Residue @ 2.5 tons per acre + Pusa decomposer; Residue @ 2.5 tons per acre + no Pusa decomposer; and absolute control. Results indicate that integrating organic and inorganic fertilizers with microbial decomposers positively affects rice growth and yield parameters. While adding microbial decomposer to RDF did not consistently enhance rice yield, it improved soil enzymatic properties. This suggests that the effectiveness of microbial decomposers may vary based on specific soil and crop conditions. Therefore, microbial decomposers present a promising approach to boost soil health and fertility. Further research is needed to optimize conditions for their use and systematically assess their impact on crop yields.

Chemical and Physical Aspects of Soil Health Resulting from Long-Term No-Till Management

The aim of this study was to compare the long-term effects of conventional tillage (CT) and no-till (NT) systems on the main soil properties that determine soil health. The research was conducted in a field experiment established in 1975 in Chylice, central Poland, at the WULS-SGGW Experimental Station Skierniewice. Soil samples collected from 0–10 and 10–20 cm of the mollic horizon of the Phaeozem were analysed for total organic carbon (TOC) content, fractional composition of SOM and spectroscopic properties of humin, soil structural stability, soil water retention characteristics and soil water repellency (SWR). The results showed that NT practice almost doubled the TOC in the 0–10 cm layer. However, optical parameters of humin indicated that NT management promoted the formation of humin with a lower molecular weight and lower degree of condensation of aromatic structures. In the NT 0–10 cm layer, a significant increase in the number of water-resistant macroaggregates was found. In the 0–10 cm layer, the water capacity increased by 9%, 18%, 22% and 26% compared to CT at (certain soil suction) pF values of 0.0, 2.0, 3.0 and 4.2, respectively. SWR occurs regardless of the cultivation method at a soil moisture equivalent to pF 4.2, and the greatest range of SWR was found in the NT 0–10 cm layer.

Long-Term Effects of Nitrogen Sources on Yields, Nitrogen Use Efficiencies, and Soil of Tilled and Irrigated Corn

Although corn is the most important and nitrogen (N)-fertilized crop, there is a lack of long-term data on the effects of organic and inorganic N fertilizers on the N balance and losses for corn systems under different tillage approaches. From 2012 to 2023, we assessed the effects of the N source on the grain yields from cultivated continuous corn receiving irrigation at a site with minimal erosion in Fort Collins, Colorado, USA, and compared these effects to no-till (NT) and strip till (ST) systems receiving inorganic N. An N balance accounting for N and carbon (C) sequestration found a system nitrogen use efficiency (NUESys) for organic N fertilizer (manure) with a tillage of 86.6%, which was higher than the NUESys of 62.6% with inorganic N fertilizer (enhanced efficiency fertilizer, EEF). Conventional tillage with manure use is a good management practice that contributed to higher grain yields (2 of 11 years), C sequestration (p < 0.05), soil organic N content (p < 0.05), and soil phosphorus (P) content than inorganic N fertilizer with tillage (p < 0.05). The tilled systems, whether receiving organic or inorganic N fertilizer, had higher yields and grain N content than the NT and ST systems receiving inorganic N fertilizer (p < 0.05). The grain production of the cultivated system receiving organic N fertilizer did not decrease with time, while the yields of the cultivated system receiving inorganic N fertilizer decreased with time (p < 0.05), suggesting that cultivated systems receiving organic N fertilizer may be more sustainable and better able to adapt to a changing climate. Additionally, a combination of manure (30% of N input) with EEF (70% of N input) contributed to a synergistic effect that increased the agronomic productivity (harvested grain yields).

Conservation Agriculture and Crop Residue Management

India being a populous country the intensification of the cropping system is mandatory. However, this intensification of the cropping system results in the degradation of soil and other natural resources. Considering this situation, conservation agriculture is the most suitable alternative to achieving sustainable yield and productivity. Conservation agriculture is based on three major principles those are minimum disturbance of soil, crop rotation, and maintenance of crop residue. Crop residue management plays a major role in conservation agriculture as it helps in improving soil productivity, soil organic matter content, soil structure, soil water conservation, air quality, and reduction in soil erosion. India produces 273 Mt of crop residues annually which contain a total of 7.16 Mt of nutrients (N-1.28, P2O5-1.97, K2O-3.91). In modern agriculture, green manure crops like Sesbania and sunhemp increase the quantity and quality of the crop residues in the crop field. Among various residue management practices mulching has been practiced prominently in dry lands as it increases the resource use efficiency. The residue decomposition is affected by various factors like quality of crop residue, edaphic, management, and climatic factors. In modern scientific research crop residues are being used especially for site-specific nutrient management. It is observed in most studies that zero tillage or reduced tillage with crop residue gives comparatively higher net returns, water use efficiency, and resource use efficiency than conventional agriculture. In Indian context. The management of rice residue particularly in the Indo-Gangetic Plains of India is challenging, where the rice-wheat cropping system is intensively followed and the farmers are more anxious about timely seeding of wheat in combine harvested paddy fields (Sidhu et al., 2007; Singh et al., 2020).

Influence of Crop Residue Management on Maize Production Potential

Residue management at the farm level is essential for ensuring sustainable agricultural productivity. This field experiment, initiated in 2005, provides maize data from 2016 to 2018. This study evaluates the impact of crop residue management and fertilization on maize yield and yield components. Maize was grown in a crop rotation sequence consisting of field pea (Pisum sativum L.), durum wheat (Triticum durum Desf.), milk thistle (Silybum marianum (L.) Gaertn.), and maize (Zea mays L.). The measures studied include aboveground biomass removal (K), aboveground biomass incorporation (R), mineral fertilizer application (F), and their combination (RF). The results indicate that R and RF significantly improve yield parameters, such as kernel number per ear (KNE), thousand seed weight (TSW), stalk yield, and harvest index (HI), compared to control (K) or aboveground biomass incorporation alone (R). Grain yield varied across the years, with significant increases being observed for the fertilizer treatments, particularly when combined with straw or stalk incorporation. A nominal increase in grain yield of 1.43 t ha−1 for the F treatment and 1.86 t ha−1 for the RF treatment represents an increase of 39% to 51% compared to K and R. Strong positive correlations were observed between grain yield and several factors, including ears per hectare (0.61), KNE (0.94), TSW (0.61), and HI (0.85). These findings underscore the role of crop residue management and promoting sustainable crop production.

IMPACTO AMBIENTAL POR USO DE PLAGUICIDAS Y SUSTENTABILIDAD DEL SISTEMA PRODUCTIVO DEL MAÍZ AMARILLO DURO EN HUAURA, PERÚ

<p><strong>Background:</strong> Hard yellow maize (MAD) is one of the main crops in economic, social and environmental terms worldwide, however, it is managed through conventional agriculture which entails a high dependence on agrochemical inputs, which cause a negative impact on the agroecosystem and through this study it will be possible to identify the critical points and establish solutions for them. <strong>Objective: </strong>To determine the coefficient of environmental impact of pesticides in the field and find the general sustainability index of the MAD production units. <strong>Objective:</strong> Determine the coefficient of environmental impact of pesticides in the field and find the general sustainability index of the MAD production units. <strong>Methodology:</strong> The environmental impact (EI ha<sup>-1</sup>) of pesticides in the field was evaluated by calculating the environmental impact coefficient (EIQ), concentration of the active ingredient, dose and number of applications. In addition, sustainability was determined through multicriteria analysis by applying 85 questionnaires with structured questions to farmers whose main activity is MAD, with economic, social and environmental indicators standardized on a scale of 1 to 5. <strong>Results:</strong> The study showed that the EI ha<sup>-1</sup> of MAD was 105.11 rated as high, which generates a negative impact on the environment and a high risk for farmers who apply these pesticides. It was also found that the sustainability index of the social and economic dimensions was 3.56 and 3.18 respectively, while the environmental index (2.64) obtained a value below the minimum sustainable threshold, therefore the MAD production system in Huaura is not sustainable. The analysis found the critical points: levels and types of fertilization (2.74), incorporation of organic matter (2.33), crop residue management (1.51), living barriers (1.36), pest control method (2.49), frequency of pesticide applications (2.53), irrigation system (2.54), level of education (2.96), quality of technical assistance and training (2.8), income from other activities (2.9) and marketing channel (1.82). <strong>Implications:</strong> Timely intervention on critical points allows establishing solution options and improving pesticide management.<strong> Conclusion: </strong>The study showed that the IE ha<sup>-1</sup> of MAD was high, indicating that the pesticides used for chemical pest and disease control generate a negative impact on the environment and a high risk for farmers who apply these pesticides. Likewise, it was found that the MAD production system is not sustainable. Therefore, the identification of the critical points allows the establishment of strategies to strengthen the MAD agroecosystem in Huaura, Peru.</p>

The LTAR Cropland Common Experiment at Lower Chesapeake Bay.

The Lower Chesapeake Bay (LCB) Long-Term Agroecosystem Research (LTAR) Common Experiment (CE) located in Beltsville, MD, focuses on research of concern to producers of the major regional crops, which are corn (Zea mays L.), soybean [Glycine max (L.) Merr.], wheat (Triticum aestivum L.), and various forage species. Livestock production in the region includes broiler and laying chickens (Gallus gallus domesticus L.) and dairy and beef cattle (Bos taurus L.). The LCB region is among the most heavily populated in the United States. Urban development pressure is high for both farms and natural areas. The need to restore Chesapeake Bay water quality is a major influence on regional agricultural practices. Conservation practices such as cover cropping, no-till agriculture, and nutrient management planning are more common in the region compared to nationally. However, farmers still face management challenges implementing practices that address water quality and the rise of herbicide-resistant weeds. Researchers at the LCB site recognize the need to protect the Chesapeake and Delaware Bays and maintain farmer profitability. The LCB CE compares a 3-year crop rotation system featuring alternative crop management (cover crop intensification, crop rotation diversification, and integrated weed management [IWM]) with a prevailing 2-year system (no cover crops and no IWM), both under continuous no-tillage, to identify the optimal balance to promote the sustainability of regional cropping systems. The LTAR LCB site provides data-driven tools and solutions to support farmers in the mid-Atlantic region.

A supervised machine learning model to select a cost-effective directional drilling tool

With the increased directional drilling activities in the oil and gas industry, combined with the digital revolution amongst all industry aspects, the need became high to optimize all planning and operational drilling activities. One important step in planning a directional well is to select a directional tool that can deliver the well in a cost-effective manner. Rotary steerable systems (RSS) and positive displacement mud motors (PDM) are the two widely used tools, each with distinct advantages: RSS excels in hole cleaning, sticking avoidance and hole quality in general, while PDM offers versatility and lower operating costs. This paper presents a series of machine learning (ML) models to automate the selection of the optimal directional tool based on offset well data. By processing lithology, directional, drilling performance, tripping and casing running data, the model predicts section time and cost for upcoming wells. Historical data from offset wells were split into training and testing sets and different ML algorithms were tested to choose the most accurate one. The XGBoost algorithm provided the most accurate predictions during testing, outperforming other algorithms. The beauty of the model is that it successfully accounted for variations in formation thicknesses and drilling environment and adjusts tool recommendations accordingly. Results show that no universal rule favors either RSS or PDM; rather, tool selection is highly dependent on well-specific factors. This data-driven approach reduces human bias, enhances decision-making, and could significantly lower field development costs, particularly in aggressive drilling campaigns.

Energy-use audit and Data Envelopment Analysis based optimization of tillage and residue management in rice-wheat system of Indo-Gangetic Plains

Energy-use audit and Data Envelopment Analysis based optimization of tillage and residue management in rice-wheat system of Indo-Gangetic Plains

Antennal olfactory responses in the black soldier fly Hermetia illucens

The Black Soldier Fly (BSF) is considered as the “crown jewel” of the insect feed industry and circular economy, significantly contributing to the 2030 Sustainable Development Goals by reducing carbon dioxide emissions and enabling circular management of organic waste, animal manure, and plant residues. Despite their industrial importance, limited knowledge about adult BSF biology has hindered optimal mass production. In this context, the present paper aims to explore the olfactory capabilities of both male and female BSF in response to various odorants commonly associated with organic decomposition in substrates suitable for mate encounters and egg laying. This will be achieved by performing electroantennographic recordings and scanning electron microscopy (SEM) observations on the antennal sensilla. Our results demonstrate for the first time the supposed olfactory capabilities of BSF antennae and present a first dataset of substances emitted by decaying organic matter detected by both male and female flies. Additionally, the current EAG recordings allowed comparisons with molecular data previously obtained through in silico and in vitro methods, highlighting the need for caution and strongly supporting a multidisciplinary approach as the best tool for investigating insect chemical ecology. These findings advance our understanding of BSF chemical ecology, which is crucial for effective reproduction and could significantly optimize global breeding systems

Migration and transformation behaviors of potentially toxic elements and the underlying mechanisms in bauxite residue: Insight from various revegetation strategies

Revegetation is a promising strategy for large-scale bauxite residue disposal and management, potentially influencing the geochemical stability of potentially toxic elements (PTEs) through rhizosphere processes. However, the geochemical behaviors of PTEs and the underlying mechanisms during bauxite residue revegetation remain unclear. This study examined the migration and transformation behaviors of PTEs and their underlying mechanisms in the bauxite residue-vegetation-leachate system under various revegetation strategies, including single and co-planting of perennial ryegrass (Lolium perenne L.) and white clover (Trifolium repens L.), over a 100-day microcosm experiment. The results showed significant decreases in pH, EC, Na, Al, and Cr levels in the leachate under various revegetation strategies, with slight increases in Cu, V, As, and Pb. Over time, the pH, EC, Na, Cr, Cu, V, Pb, and As levels in the leachate decreased, while those of Al, Fe, Mn, and Zn increased. The mean pH, EC, and concentrations of Na, Al, Fe, and Cr in the leachate of the revegetated treatments decreased by 6%-8%, 21%-33%, 2%-4%, 19%-27%, 7%-22%, and 15%-26%, respectively, while the mean concentrations of Mn, V, Zn, and As increased by 47%-134%, 26%-46%, 39%-47%, and 3%-10%, respectively, compared to the unamended treatment. Co-planting generally exhibited a greater impact on leachate components compared to single planting. Available contents of Al, Cr, and Pb decreased by 81%-83%, 57%-77%, and 55%-72%, respectively, while those of other PTEs increased in the revegetated bauxite residue. Co-planting significantly reduced the availability of PTEs compared to single planting. Except for Na and Mn, the bioaccumulation and transportation factors of PTEs in both vegetation species remained below 1 under various revegetation strategies. The migration and transformation behaviors of PTEs in the bauxite residue-vegetation-leachate system were mainly influenced by pH and nutrient levels. These findings provide new insights into the migration and transformation behaviors of PTEs during bauxite residue revegetation.

Theoretical Analysis of Drilling Fluid Flow for Maxi-Horizontal Directional Drilling

Theoretical Analysis of Drilling Fluid Flow for Maxi-Horizontal Directional Drilling