Straw Application Research Articles

Advancements in Biological Strategies for Controlling Harmful Algal Blooms (HABs)

Harmful algal blooms (HABs) are a primary environmental concern, threatening freshwater ecosystems and public health and causing economic damages in the billions of dollars annually. These blooms, predominantly driven by phytoplankton species like cyanobacteria, thrive in nutrient-rich, warm, and low-wind environments. Because of the adverse impacts of HABs, this review examines various control methods, focusing on biological strategies as sustainable solutions. While effective in disrupting algal populations, traditional chemical and physical interventions carry ecological risks and can be resource-intensive. Biological control methods, including biomanipulation and using algicidal microorganisms such as Streptococcus thermophiles, Myxobacteria, and Lopharia spadicea, emerge as eco-friendly alternatives offering long-term benefits. Additionally, barley and rice straw application has demonstrated efficacy in curbing HAB growth. These biological approaches work by inhibiting algal proliferation, disrupting cellular structures, and fostering algal cell aggregation. Despite their advantages over conventional methods, biological controls face challenges, including intricate ecological interactions. This article delves into the latest biological techniques aimed at eradicating HABs, intending to diminish their frequency and reduce toxin levels in aquatic environments. While most research to date has been confined to laboratory settings, scaling these methods to field applications presents hurdles due to the variability and complexity of natural ecosystems. The review underscores the need for further research and development in this critical area of environmental science.

Ammoniated straw returning: A win-win strategy for increasing crop production and soil carbon sequestration

Increasing crop production and soil carbon sequestration is critical for sustainable agricultural development. Straw returning, a common agricultural practice, positively affects grain yield and soil organic carbon. Nevertheless, the slow decomposition rate and high carbon-to-nitrogen ratio of straw are significant obstacles to its effectiveness. Ammonifying straw using urea and calcium hydroxide may be a promising solution, whereas limited information is available on the impacts of ammoniated straw returning on crop production and soil carbon sequestration. Therefore, in a winter wheat-summer maize rotation system, we conducted an experiment with three straw returning treatments (T1, straw removal; T2, traditional straw returning; T3, ammoniated straw returning) to investigate their impacts on crop growth, grain yield and yield components, carbon inputs and outputs, and net ecosystem carbon budget (NECB). The results showed that T3 outperformed T2 regarding increasing leaf area index and aboveground biomass. Ear density and thousand kernel weight of winter wheat and hundred kernel weight of summer maize were ranked T1 < T2 < T3, with no significant differences between treatments for other grain yield components. Consequently, winter wheat, summer maize, and annual grain yields were the highest under T3, followed by T2 and T1. In comparison with T1, T2 and T3 increased annual total carbon inputs by 5463 and 7271 kg C ha–1, respectively, due to the increased carbon inputs from returned straw and net primary productivity. Annual carbon total outputs, primarily from aboveground biomass removal at harvest and carbon respiration, increased by 3305 kg C ha–1 under T2 and 4264 kg C ha–1 under T3, compared with T1. Balancing annual total carbon inputs and outputs, T1, T2, and T3 had annual NECB values of –1215, 944, and 1793 kg C ha–1, respectively. Therefore, the T1 agroecosystem acted as a carbon source, whereas the T2 and T3 agroecosystems, particularly T3, acted as a carbon sink on an annual scale. These results suggest that ammoniated straw returning may be a superior straw application practice for increasing crop production and soil carbon sequestration simultaneously.

Subsoil SOC increased by high C:N ratio straw application with optimized nitrogen supplementation

AbstractThe application of straw and nutrients to agricultural subsoils is of significant interest to enhance carbon (C) sequestration and soil fertility. However, little research has explored the effect straw application on microbial stoichiometry, soil organic carbon (SOC) mineralization and accumulation and their relationships, in subsoil. In order to address these knowledge gaps, we examined the soil characteristics (organic carbon mineralization, available nutrient contents and microbial stoichiometric ratio) under straw addition (maize leaf and stem) with and without nitrogen (N) supplementation (no addition, 30 mg N kg−1 dry soil−1, 60 mg N kg−1 dry soil−1) during an 80‐day incubation experiment. The microbial stoichiometric ratio imbalance (C:N and C:Phosphorus (P)) and extracellular enzyme stoichiometry were measured as indicators of the systematic relationship between soil resource availability and the mineralization of organic carbon. Our study demonstrated that the addition of straw significantly enhanced CO2 emissions and led to an increase in the C:N imbalance, while simultaneously decreasing microbial carbon use efficiency (CUE). In addition, stem addition showed 5.6% lower CUE, but 8.2% higher SOC compared with leaf addition. We also found that nitrogen addition to subsoil alleviated microbial nitrogen limitation. 60 mg N kg−1 dry soil rates of nitrogen application had a positive effect on reducing C:N imbalance and promoting the accumulation of SOC. Extracellular enzyme activity and microbial stoichiometric ratio were the most important controlling factors of SOC mineralization and microbial CUE, respectively. In conclusion, the application of straw alongside N to balance stoichiometric ratios can significantly increase SOC content, indicating the potential for carbon sequestration in agricultural subsoils.

Efficient removal of tetracycline in water using modified eggplant straw biochar supported green nanoscale zerovalent iron: synthesis, removal performance, and mechanism.

A novel NaOH modified eggplant straw biochar supported green nanoscale zerovalent iron (P-nZVI/ESBC) composite was synthesized and its removal performance and reaction mechanism for tetracycline (TC) in water were investigated. Multiple characterizations showed that the prepared P-nZVI/ESBC composite contained oxygen-containing functional groups (hydroxyl, carbonyl, and carboxyl groups) and Fe species (nZVI and its oxides). The dosage of composite, temperature, and solution pH significantly affected the removal capacity of the P-nZVI/ESBC composite for TC. The Avrami fraction-order kinetic model and Sips adsorption isotherm model can fit well the removal process of TC by the P-nZVI/ESBC composite, indicating that the adsorption behavior of TC involved multiple adsorption mechanisms and chemical adsorption might occur. The maximum adsorption capacity of the P-nZVI/ESBC composite for TC was 304.62 mg g-1. The adsorption and reductive degradation were the dominant mechanisms of TC removal by the P-nZVI/ESBC composite. This work offers abundant information on the application of eggplant straw to manufacture biochar-based composites for the efficient removal of antibiotic contaminants from aquatic environments.

An appropriate amount of straw replaced chemical fertilizers returning reduced net greenhouse gas emissions and improved net ecological economic benefits

With the increasing application of crop straw, the greenhouse gas emissions caused due to crop straw have received increasing attention. However, the current studies have not explored the greenhouse gas emissions from on-farmland consumption of returned straw. Based on a long-term positioning experiment, three treatments were set up in double-cropping rice fields: chemical fertilizer (CF), straw replacing 1/3 nitrogen fertilizer (MS), and straw replacing 2/3 nitrogen fertilizer (HS). We measured the biomass, soil properties, and greenhouse gas emissions of double-cropping rice and then comprehensively evaluated the global warming potential, carbon footprint, and net ecological and economic benefits. The straw treatments (MS and HS) increased the cumulative annual emissions of CH4 (98.44% and 261.23%), CO2 (30.85% and 122.29%), and N2O (7.37% and 52.50%), the cumulative annual global warming potential (74.15% and 206.12%), average GHG intensity (43.26% and 138.07%), and the annual cumulative net ecosystem carbon budget (52.96% and 100.97%) in the early and late rice growing seasons, respectively. We observed that the real-time greenhouse gas emissions were significantly correlated to the soil microbial functional genes and total carbon, NH4+-N, and NO3−-N. The results of the random forest model showed that total carbon (13.87%) and nirK abundance (9.80%) were the highest predictors of global warming potential at the booting and maturity stages, respectively during rice growing season. Combining the resource inputs for agricultural production and the greenhouse gas emission potential of the returned straw on its own, MS showed the lowest net greenhouse gas emission, and MS and HS showed significantly increased annual cumulative net ecological economic benefits (38.08% and 34.30%). Overall, MS showed the lowest net greenhouse gas emission and the highest net ecological economic benefits, which is a straw-returning measure with low environmental impact and high economic returns.

Improving the Physical Properties and Water Retention of Sandy Soils by the Synergistic Utilization of Natural Clay Deposits and Wheat Straw

Improving the physical properties and water retention of sandy soils is of critical importance in arid and water-scarce regions such as Saudi Arabia. The impacts of organic amendments of different particle sizes coupled with natural clay deposits on improving the soil physio-chemical characteristics, nutrient availability, and growth of Sudan grass were investigated in this study. A loamy sand soil was amended with natural clay deposits at 2.5%, 5.0%, and 10% (w/w) application rates, and in combination with 1.0% (w/w) wheat straw of different particle sizes. The water infiltration, evaporation, and retention characteristics of the amended soil were studied for 9 weeks, and then Sudan grass was grown for 7 weeks. The impacts of the particle size of wheat straw on soil properties and nutrient availability were significant (p &lt; 0.05) when combined with clay deposits. The highest application rate of clay (10%) demonstrated the highest water content (20.63–21.73%), and increased P and K availability to 35.54 and 6980 mg kg−1, respectively, in soil, which were 33% and 88% higher, respectively, compared to the control. Plant N, P, and K concentrations were increased to 0.95%, 0.26%, and 4.33%, respectively, which were 2–3.5-fold higher than the control. Therefore, the integrated application of natural clay deposits and wheat straw of fine particle size could be an effective strategy in improving plant production in water-scarce regions.

Response of Microbial Recovery Rate to Straw Return after Calcium Cyanamide Soil Disinfection

At present, returning vegetable straw in situ is an effective measure to solve environmental pollution and improve soil properties. However, the direct return of straw to the field can reduce the release rate of soil organic matter and cause serious soilborne diseases. The combined application of calcium cyanamide (CaCN2) and straw can solve this problem. The objective of this study was to determine the effect of CaCN2 combined with pepper straw return on cucumber yield, soil physicochemical properties, and soil microbial communities during 2020 to 2021 in Shandong Province, China. The treatments were designed as follows: (1) calcium cyanamide soil disinfection, CC; (2) fresh pepper straw return, LJ; (3) fresh pepper straw return combined with calcium cyanamide disinfection, LJ+CC; and (4) natural soil without straw return treatment, CK. Compared with CK, the LJ+CC treatment significantly improved cucumber production by 20%. The cultivable microbial community in the soil was temporarily inhibited during soil fumigation treatment, and the cultivable bacterial and actinomycete communities in the soil return to their initial levels after the film was removed (harvest period). The numbers of culturable bacteria and actinomycetes in the soil in the LJ+CC treatment were 4.68 × 107 CFU/g and 5.17 × 107 CFU/g, respectively, higher than those in the soil in the CC treatment. The contents of TN and OM in the LJ+CC treatment increased by 13.1% and 13.5%, respectively, compared with that in LJ. Therefore, the LJ+CC treatment enhanced soil fertility and cucumber yields. CaCN2 can promote straw decomposition and straw can promote soil microbial recovery, and their combined application is considered a feasible and sustainable technique for utilizing vegetable residues in the greenhouse. The combination of returning pepper straw to the field and calcium cyanamide technology achieves a win-win situation of resource circulation and economic circulation by converting agricultural waste into fertilizer before being put into production. Based on this, it is recommended that the straw returning technology receives strong policy support, stimulates researchers to explore the feasibility of different vegetable straw returning to the field, promotes the implementation of this technology achievement, and leverages the environmental benefits of the application of straw returning technology.

Evaluating short-term effects of rice straw management on carbon fractions, composition and stability of soil aggregates in an acidic red soil with a vegetable planting history

Red soils are characterised by acidic pH and limitations in carbon, nitrogen, water, and soil structure. To overcome such limitations, improved soil aggregation is the key to improving the physical and chemical properties of soil. Applying organic amendments such as straw can lead to corresponding soil aggregation and stability changes. Therefore, we explored the short-term effects of rice straw amendment, either alone or in combination with biochar, on improving the carbon fractions, stability, and composition of soil aggregates in red soil with a history of vegetable planting. The study consisted of four treatments: control (no organic material, CK), biochar alone (5% homemade straw biochar, B), straw alone (12% rice straw, S), and biochar with straw (5% homemade straw biochar + 12% rice straw, BS). Our results showed that equal amounts of straw and biochar substantially reduced the number of mechanically stable aggregates (MSA), mean weight diameter (MWD), and geometric mean diameter (GMD) of the soil. BS treatment reduced >0.25 mm aggregate content (R0.25), MWD and GMD by 24.06%, 56.81%, and 62.19%, respectively, compared with that of the control. The addition of straw greatly enhanced the water-stable macromolecular content and stability coefficient of the soil, but treatment B had no obvious effect. The S treatment had the greatest effect on R0.25, MWD and GMD, increasing them by 143.94%, 246.67%, and 181.82%, respectively, compared with that of the control. Soil organic carbon (SOC) was significantly increased by straw addition and carbonisation treatment, and the effect of the BS treatment was the best, with an increase of 325.63% compared with that of the control. The organic carbon content in the aggregates of different particle sizes treated with different organic materials also increased significantly. In the soil reactive organic carbon fraction, applying biochar alone did not affect microbial biomass carbon (MBC), dissolved organic carbon (DOC), or easily oxidized organic carbon (EOC) but could increase the particulate organic carbon (POC) content. All the treatments with straw application significantly increased the MBC, DOC, EOC, and POC content, and the highest effect was obtained by applying both straw and biochar in an integrated form, i.e., the BS treatment. In conclusion, the co-application of biochar and straw sequestered more carbon and revamped soil C pools than either biochar or straw alone and could be a promising option for the sustainable use of red soils to ameliorate the aforementioned limitations associated with this soil type.

Low-Temperature Fermented Straw Compost Regulates Rice Growth and Yield by Affecting Soil Physicochemical Properties and the Expression of Important Signaling Pathway Genes

Soil physicochemical properties affect crop growth and yield. The addition of fertilizers can improve the soil quality during crop cultivation, leading to increased agricultural production. Organic fertilizers may be produced by composting straw that would otherwise be discarded as agricultural waste, with potential implications for sustainable agricultural development. However, the mechanism underlying the effects of straw compost on crop growth is unknown. In this study, a microbial agent suitable for straw decomposition in cold regions was used for a large-scale biological fermentation. Organic compost was obtained after the decomposition of straw. The straw compost was mixed with soil in different proportions and then used to cultivate Songjing 2 rice plants. The addition of straw compost significantly increased the growth and yield of the rice plants and enhanced various physiological indices. Moreover, the straw compost treatment significantly improved soil physicochemical properties (e.g., pH, enzyme activity, nutrient composition, and microbial diversity) and optimized the soil conditions for crop growth. In addition, the application of straw compost influenced the expression of genes in rice metabolic pathways as well as pathways mediating secondary metabolite synthesis and plant hormone signal transduction. The study data reflect the potential applicability of low-temperature straw fermentation technology for maximizing crop production.

OPTIMIZATION OF NITROGEN FERTILIZATION FOR AGRICULTURAL CROPS UPON ADDITIONAL APPLICATION OF FRESH ORGANIC MATTER TO THE SOIL

Objective. Using biological testing, determine the environmental appropriate rates of mineralnitrogen, applied in the background of effect and aftereffect of straw and biomass of intermediatelupine green manure, in the fertilization system of potatoes and spring barley. Methods. Field experiment (growing crops in crop rotation in the conditions of a long-term (since 2009) stationaryexperiment on leached chornozem); gas chromatographic (to determine the potential nitrogenfixing (nitrogenase) and potential denitrifying activities in the rhizosphere soil of plants dependingon the fertilizer); statistical. Results. With the systematic application of fresh organic matter to thesoil in the form of 5.0 t/ha of straw and 5.3 t/ha of dry biomass of intermediate lupine green manure, the excess of nitrogen mineral compounds is metabolically bound (immobilized) by microorganisms, the process of nitrogen fixation is restored, the emission of N2O decreases, and the ratesof mineral fertilizers not exceeding N80P80K80 become environmentally appropriate when growingpotatoes. At the same time, the introduction of straw does not require additional provision of mineral nitrogen to optimize the C/N ratio. The highest rate of mineral fertilizers N120P120K120 in theexperiment, even when combined with organic matter for a long time is environmentally inappropriate — only at the end of the growing season, the studied indicators demonstrate its acceptability.When growing spring barley on leached chornozem, the optimization of the processes of biologicaltransformation of nitrogen compounds is achieved if mineral fertilizers are applied on the background of aftereffect of organic matter in a rate not exceeding N60P60K60. Systemic application ofN90P90K90 suppresses the activity of nitrogen fixation and ensures significant losses of nitrous oxide.This rate of fertilizers should be applied only on the condition that it is applied against the background of the aftereffect of straw and green manure mass, which contributes to the mitigation ofenvironmental consequences. Conclusion. The use of mineral fertilizers against the backgroundof systematic application of winter wheat straw and intermediate lupine green manure biomass tothe soil contributes to the optimization of the biological state of the leached chornozem. The improvement of environmental indicators contributes to the growth of the yield of agricultural crops.

Straw incorporation into microplastic-contaminated soil can reduce greenhouse gas emissions by enhancing soil enzyme activities and microbial community structure

Microplastic (MP) contamination poses a substantial threat to agroecosystems, disrupting soil properties, nutrient cycles, and microbial communities and ultimately affecting plant growth and ecosystem resilience. The effects of straw addition on the storage of soil organic carbon (SOC) and greenhouse gas emissions have been extensively explored, but these effects have not been examined in the context of MP contamination. To assess the impacts of legume straw and polyethylene microplastics on SOC fractions and carbon dioxide (CO2) and nitrous oxide (N2O) emissions, 7-month soil incubation experiments were performed. The results revealed that the inclusion of legume straw in soil considerably increased microbial SOC compared to the control. However, straw addition to MP-contaminated soil reduced microbial SOC compared to that in soil containing only straw. In contrast, the addition of straw to MP-contaminated soil elevated (+44%) the SOC mineral relative to the sole application of straw. Intriguingly, straw incorporation into MP-contaminated soil reduced microbial biomass carbon and nitrogen relative to soil containing only straw. Straw addition to MP-contaminated soil enhanced the nitrification activity and reduced the relative expression of AOBamoABC gene compared to sole straw-incorporated soil and the control. Greenhouse gas emissions were also modulated; for instance, straw incorporation into MP-contaminated soil reduced CO2 and N2O emissions by −11% and −46%, compared to straw incorporation alone. The urease and phosphatase activities were decreased (−58% and −12%) in the MP-polluted soil with straw incorporation compared with those in the soil in which only straw was applied. However, invertase and catalase activities were upregulated in the straw-incorporated soil contaminated with MPs. Straw addition in the MP-polluted soil considerably enhanced (+2%) the microbial community structure (indicated by PLFA) compared to the sole straw application. These results provide a comprehensive perspective on the role of legume straw incorporation in addressing MP pollution, showcasing its potential for sustainable agricultural practices in the face of evolving environmental challenges.

Cartographic modeling of humus content dynamics in the soils of Zdolbuniv district of Rivne region

Soil agrochemical testing allows us to make optimal decisions to restore soil fertility, use fertilizers and pesticides efficiently, increase agricultural productivity and preserve the environment. Among the main agrochemical properties of soils, an important place belongs to the humus content, which is the organic part of the soil formed as a result of the decomposition of plant and animal residues and products of organisms' vital activity. This organic matter is a class of chemical compounds whose main components are carbon, as well as nitrogen, phosphorus, sulfur, and other elements. The main importance of humus in the soil is as follows: it helps to increase water absorption and air permeability; increases the level of dissolved macro- and microelements; and supports biological activity. Based on the results of the IX–XI rounds (2007–2017) of the planned agrochemical certification of the lands of Zdolbuniv district of Rivne region, conducted by the State Soil Protection Service, a corresponding database was created and thematic maps of soil humus content were constructed. The author's maps were developed for different years at a scale of 1 : 250 000 using ArcMap software, using the Gauss-Kruger projection and the Pulkovo 1942 GK Zone 5 coordinate system, with cartograms as the main method of depiction. The maps, in the context of the territories of former village councils (before the administrative-territorial reform of 2020), provide qualitative and quantitative information on humus content using a standard color scale and appropriate symbols. On the territory of Zdolbuniv district, which covers an area of 66.1 thousand hectares, the most common among the surveyed agricultural lands are light gray podzolized slightly stony (16.8 %), dark gray podzolized (13.8 %), light gray and gray podzolized medium-washed (11.7 %) and gray podzolized slightly washed (10.3 %) soils. The presented thematic maps show the spatial distribution of humus content in the soil by former village councils. This makes it possible to identify areas with different values of the indicators and to identify possible problematic or potentially fertile lands. The maps also show specific quantitative weighted average values of soil humus content for village councils, which makes it possible to determine changes in the indicator over the period in question for individual territorial units. In this regard, the best indicators are observed on the lands of Mizotska and Pyatihirska councils (the average humus content increased by 0.9–1.0 %), and the worst on the lands of Buderazhska council (the average humus content decreased by 0.3 %). As a result of the research, it was found that the generalized average humus content in the soil in the surveyed area for each tour ranged from 2.2 % to 2.6 %. According to classification criteria, this corresponds to lands with an average humus content (2.1–3.0 %). In the context of village councils, the weighted average humus content during this period ranged from 1.5 % to 3.1 %, meaning that the land belonged to 3 groups of land: low, medium, and high humus content. Low humus content in the soil is an indication of insufficient retention of organic matter, which can usually be the result of improper tillage, limited use of fertilizers, erosion processes, and suboptimal crop rotation. The average humus content is a sign of moderate farming, a certain stability of the soil's ecological condition, but still requires certain measures to maintain its fertility. Soils with high humus content are quite fertile and favorable for crop production. In case of small volumes or absence of manure application, peat use, plowing green manure, straw application can stabilize the state of biologization of agriculture to some extent. The thematic maps and diagrams created in this way allow, with the help of other additional and more detailed data, to become the basis for making informed management decisions on optimizing the humus content in the soil, growing crops, modeling changes in soil cover properties, and making agrochemical forecasts. Keywords: humus, agrochemical properties, cartographic modeling, thematic maps, cartograms.

Research Progress on Soil Carbon Sequestration in Dry Farmland

Dry farming is a kind of agricultural production mode widely existed in the world, and its soil carbon sequestration potential has attracted much attention. The paper discussed the influencing factors, carbon sequestration process and effect of soil carbon sequestration in dryland farmland. It was concluded that protective tillage measures such as application of organic fertilizer, no-tillage, deep tillage and straw returning could increase the carbon sequestration in surface dryland soil, biodegradable film mulching could promote soil organic carbon fixation, and rational arrangement of crops could improve soil carbon sequestration capacity.

Mitigating CO2 emissions from cultivated peatlands: Efficiency of straws and wood chips applications in maintaining carbon stock in two contrasting soils

Repeated applications of straw and wood chips were recently proposed as a conservation strategy for preserving cultivated peatland carbon (C) stock. However, the variability in the amendment biostability and the possible divergent responses of contrasting peat soils need to be assessed. This study investigated the effect of amendment with different plant materials on carbon dioxide (CO2) emissions from two contrasting peat soils (sapric and hemic) in two laboratory experiments. The sapric soil received one application of plant materials and was incubated for 3190 degree-days (145 days at 22°C), while the hemic soil received three successive applications of plant materials and was incubated for three successive periods of 3150 degree-days (126 days at 25°C). CO2 emissions were measured at time intervals ranging from 2 to 14 days and the apparent proportion of the plant material’s C remaining in the soil was modeled using an exponential decay function. CO2 emissions from the 0-25 cm horizon of the unamended peats represented 0.7 t C-CO2 ha-1 yr-1 in the sapric soil and 7.3, 1.1, and 0.5 t C-CO2 ha-1 yr-1 in the hemic soil for the first, second, and third amendment periods, respectively. The apparent remaining C of the plant material varied from 52% to 81% in the two experiments, resulting in biomass requirements ranging from 2 to 32 t ha-1. The apparent remaining C was from 26% to 36% higher in the sapric soil than in the hemic soil. The apparent remaining C was also 9% to 38% higher for the treated softwoods than the untreated materials (straws: miscanthus, switchgrass, sorghum; wood chips: willow, birch). The repeated application of straw and wood chips increased CO2 emissions in the first 35 days following each application, resulting in an increased decomposition rate for the tested model. However, no change was detected for the final apparent remaining C across the three applications. These findings highlight the importance of considering soil properties, material types, and the impact of repeated applications for designing effective amendment programs and accurate C projection models for cultivated peatlands.

Effect of Furrow Straw Mulching and Straw Decomposer Application on Celery (Apium graveolens L.) Production and Soil Improvement

Straw mulching on wet beds is an effective method to alleviate continuous cropping obstacles in greenhouses. However, this technique cannot be applied in the production of leafy vegetables with high planting density. Straw mulching in furrows is an alternative method in this circumstance. In this study, celery (Apium graveolens L.), a vegetable that prefers a high planting density and wet soil, was used to test furrow straw mulching technology, and the effect of different straw amounts and straw decomposers on soil improvement and celery production was investigated. The results showed that straw mulching in furrows significantly reduced soil conductivity and nitrate nitrogen levels, increased the contents of soil organic carbon as well as phosphorus and potassium nutrients in the bed, and improved celery yield and quality, indicating the significant lateral movement of released nutrients between the furrow and bed. The positive effects of 15,000 kg/ha straw application were more pronounced than those of 7500 kg/ha and 11,250 kg/ha. In addition, straw decomposers accelerated nutrient release and improved celery yield and quality. A decomposer named “ZhuBang” containing Bacillus licheniformis was the most effective. We concluded that furrow straw mulching combined with straw decomposer application is an effective measure for the sustainable production of leafy vegetables in intensive vegetable production facilities.

Application of herbicides and sugar cane straw on controlling of Mucuna aterrima L. in peanut crop

Peanut crop is normally cultivated in sugar cane renewal areas in Brazil, where velvet bean (Mucuna aterrima) is a troublesome weed, in which the control is essential. The goal was to evaluate herbicide efficacy associated with sugar cane harvest residues on M. aterrima control. In absence and presence of sugar cane straw, herbicides were applied in pre-emergence (imazapic, imazethapyr + flumioxazin, diclosulan, s-metolachlor, clomazone, sulfentrazone and sulfentrazone+diuron) and in post-emergence of M. aterrima (imazapic, imazethapyr, bentazon, bentazon + imazamox, lactofen, fomesafen, cloransulan-methyl, carfentrazone and 2,4-D). The treatments sulfentrazone and sulfentrazone + diuron resulted in control higher than 95% in straw absence, causing the highest reductions on aerial part (92%) and root (64%) drought mass of M. aterrima. The presence of sugar cane straw reduced the effect of herbicides applied in pre-emergence. The 2,4-D resulted in weed control higher than 70% and the applications with 2,4-D and carfentrazone caused the highest reductions on weed plant height (28%), aerial part (45%) and root (42%) drought mass. It was possible to conclude that the highest control levels of M. aterrima were obtained with sulfentrazone and sulfentrazone + diuron applied at pre-emergence, in absence of sugar cane straw and, with 2,4-D and carfentrazone, applied in post-emergence, regardless of straw presence

Effects of Different Conditioners on Humus Composition and Humic Acid Structural Characteristics in Black Soil Under the Combined Application of Pig Manure and Straw

Effects of Different Conditioners on Humus Composition and Humic Acid Structural Characteristics in Black Soil Under the Combined Application of Pig Manure and Straw

Comparative biotic and abiotic effects on greenhouse gas emissions from agricultural ecosystems: application of straw or biochar?

Farmland has become a significant contributor to greenhouse gas (GHG) emissions, and research has shown that the addition of straw or biochar may be a viable method for mitigating these emissions. However, there is a lack of understanding regarding the comparative biotic and abiotic effects of straw and biochar amendments on GHG emissions. To address this knowledge gap, we conducted a meta-analysis of 100 published papers to quantify the impact of straw and biochar application on GHG emissions. Our findings indicate that straw application significantly increased CO2 and CH4 emissions from agricultural ecosystems by 46.2% and 113.5%, respectively, but did not have a significant effect on N2O emissions. Conversely, biochar amendment significantly reduced CO2, CH4, and N2O emissions by an average of 11.0%, 31.7%, and 22.8%, respectively. We also found that straw and biochar amendments increased soil pH, soil organic carbon (SOC), and C/N ratio, and there were significant differences between them. Moreover, straw application significantly increased the microbial biomass carbon (MBC) content and microbial quotient by 37.1% and 20.1%, respectively, while biochar application increased the MBC content by 25.0% without a significant effect on the microbial quotient. Furthermore, both straw and biochar applications promoted the nitrification process and increased the abundance of ammonia-oxidizing bacteria (AOB) by 50.7% with straw and by 57.5% and 75.1% with biochar for ammonia-oxidizing archaea (AOA) and AOB, respectively. The denitrification process was also stimulated by straw or biochar amendment, resulting in an increase in the abundance of nirK by 22.9% and 16.8%, respectively. Biochar amendment additionally increased the abundance of nosZ by 29.4%, indicating that the main reason for reducing N2O emissions through biochar application is the conversion of NO3--N to N2. Thus, compared to straw application, biochar application is a more effective method for reducing greenhouse gas emissions.

High-Value Utilization of Corn Straw: From Waste to Wealth

As a renewable lignocellulosic biomass resource, corn straw has great potential for waste utilization in agriculture and sustainable development. In recent years, considerable attention has been given to the research on repurposing organic acids, saccharides, and other active substances extracted from corn straw. This review is focused on the progress in the preparative techniques and product development of organic acids and saccharides, realizing the high-value utilization of corn straw. This review also discusses the potential applications of corn straw in the food and biopharmaceutical industries, and sheds light on the current challenges and future directions in the efficient utilization of straw resources.

Maize straw application reduced cadmium and increased arsenic uptake in wheat and enhanced the rhizospheric bacterial communities in alkaline-contaminated soil

Many fields where wheat is grown in northern China are co-polluted by arsenic (As) and cadmium (Cd). Thus, remediation of As and Cd-contaminated alkaline soils is crucial for safe wheat production. In this study, a pot experiment was carried out to investigate the impact of 1% and 2% maize straw (MS) incorporation on As and Cd bioavailability, binding forms, uptake by winter wheat (Triticum aestivum L.), and bacterial communities in smelter (SS) and irrigation (IS) alkaline contaminated soils. The results indicated that 2% MS incorporation significantly (p < 0.05) increased bioavailable-As by 37% (SS) and 39% (IS) with no significant change in the bioavailable-Cd in SS2% (31.95%) from 31.95% (SSCK) and IS2% (33.33%) from 32.82% (ISCK). Incorporation of 2% MS increased the grain As concentration from 0.22 mg kg−1 (SSCK) to 0.51 mg kg−1 (SS2%) and from 0.59 mg kg−1 (ISCK) to 0.84 mg kg−1 (IS2%) which is above the acceptable standard of 0.5 mg kg−1 (GB2726-2017). In contrast, the Cd content in grains was maintained at 0.09 (SS1%), 0.04 (SS2%) and 0.03 (IS1%), 0.02 (IS2%) below the acceptable standard of 0.10 mg kg−1 (GB2762–2017). The amendment through dissolved organic carbon mediated As desorption enhanced As transfer to wheat grain, decreasing DTPA-Cd in the soils and its consequent translocation to wheat leaves and grain. The 2% MS incorporation increased the active As fractions, reduced mobile Cd into immobile fractions, and promoted the abundance of Actinobacteria, Bacteroidetes, and Firmicutes in the two soils. These attributes of MS in decreasing the accumulation of Cd in wheat leaves and grains signified its potential as a suitable ingredient for Cd sequestration and food safety in Cd-contaminated soils.