Peanut Straw Research Articles

Degradation of ciprofloxacin hydrochloride in a multiphase mixed system by subaquatic gas-liquid discharge plasma

In recent years, antibiotic pollution has become a serious threat to human health. In this study, a gas-liquid discharge plasma is developed to degrade ciprofloxacin hydrochloride in a multiphase mixed system containing inorganic and organic impurities. The discharge characteristics are analyzed by diagnosing the applied voltage and discharge current waveforms, as well as the optical emission spectra. The work investigates how degradation efficiency is affected by applied voltage, gas flow rate, treatment time, initial concentration as well as the addition of γ-Al2O3 pellets and peanut straw. After 70 min, the degradation efficiency of ciprofloxacin hydrochloride in the multiphase mixed system reached 99.6%. Its removal efficiency increases as the initial concentration decreases and the applied voltage increases. Besides, there is still a good degradation efficiency of ciprofloxacin hydrochloride with the addition of peanut straw. The degradation mechanism of ciprofloxacin hydrochloride is investigated through the analysis of degraded intermediates and reactive species.

Effect of peanut straw mulching on the soil nitrogen change and functional genes in the Camellia oleifera intercropping system

Effect of peanut straw mulching on the soil nitrogen change and functional genes in the Camellia oleifera intercropping system

Improved Straw Decomposition Products Promote Peanut Growth by Changing Soil Chemical Properties and Microbial Diversity

The ameliorative effects of straw decomposition products on soil acidification have been extensively studied. However, the impact of chemically treated straw decomposition products on crop productivity and the underlying microbial mechanisms remain unclear. This study aimed to investigate the effects of two dosages of Ca(OH)2-treated straw decomposition products of peanuts on red soil acidity, fertility, and bacterial and fungal diversity through a pot experiment. The pot experiment included four treatments: chemical nitrogen, phosphorus, and potassium (NPK) fertilization alone (CK), NPK chemical fertilization combined with peanut straw decomposition products (PS), NPK chemical fertilization combined with 4% Ca(OH)2-treated peanut straw decomposition products (PS4Ca), and NPK chemical fertilization combined with 8% Ca(OH)2-treated straw decomposition products (PS8Ca). High-throughput sequencing was performed to investigate the effects of these treatments on soil microbial diversity. The treatments with PS, PS4Ca, and PS8Ca significantly increased soil pH, exchangeable base cations, and nutrient content, whereas they decreased the exchangeable acid, especially exchangeable aluminum. The peanut growth improved substantially with the application of straw decomposition products. Specifically, PS4Ca significantly increased the Shannon and Richness indices of fungi. The principal coordinate analysis showed that the soil microbial communities in the straw decomposition product treatments were significantly different from CK. Linear discriminant analysis effect size identified unique bacteria and fungi between treatments. The Mantel test indicated that exchangeable base cations and pH were significantly positively correlated with bacterial communities, whereas available potassium was positively correlated with fungal communities. The partial least squares path modeling revealed that the bacterial communities positively and directly affected all peanut agronomic traits. In contrast, the fungal communities had a negative and direct effect only on peanut 100-pod weight. Therefore, adding Ca(OH)2-treated straw decomposition products could effectively improve crop productivity by alleviating soil acidification, increasing soil nutrients, and subsequently changing microorganisms.

Alteration of soil pH induced by submerging/drainage and application of peanut straw biochar and its impact on Cd(II) availability in an acidic soil to indica-japonica rice varieties

The effects of soil pH variations induced by submergence/drainage and biochar application on soil cadmium (Cd) availability to different rice (Oryza sativa L.) varieties are not well understood. This study aims to investigate the possible reasons for available Cd(II) reduction in paddy soil as influenced by biochar and to determine Cd(II) absorption and translocation rates in different parts of various rice varieties. A pot experiment in a greenhouse using four japonica and four indica rice varieties was conducted in Cd(II) contaminated paddy soil with peanut straw biochar. The results indicated that the submerging led to an increase in soil pH due to the consumption of protons (H+) by the reduction reactions of iron/manganese (Fe/Mn) oxides and sulfate (SO42−) and thus the decrease in soil available Cd(II) contents. However, the drainage decreased soil pH due to the release of protons during the oxidation of Fe2+, Mn2+, and S2− and thus the increase in soil available Cd(II) contents. Application of the biochar increased soil pH during soil submerging and inhibited the decline in soil pH during soil drainage, and thus decreased soil available Cd(II) contents under both submerging and drainage conditions. The indica rice varieties absorbed more Cd(II) in their roots and accumulated higher amounts of Cd(II) in their shoots and grains than the japonica rice varieties. The Cd(II) sensitive varieties exhibited a greater absorption and translocation rate of Cd(II) compared to the tolerant varieties of both indica and japonica rice. Biochar inhibited the absorption and accumulation of Cd(II) in the rice varieties, which ultimately lowered the Cd(II) contents in rice grains below the national food safety limit (0.2 mg kg−1). Overall, planting japonica rice varieties in Cd(II) polluted paddy soils combined with the use of biochar can effectively reduce Cd(II) content in rice grains which protects human health against Cd(II) toxicity.

Enhanced methane production from source-separated human feces (brown water) by single phase anaerobic co-digestion: Effects of different co-substrates

Based on the concept of source separation of brown water (BW, human feces with flushing water) and yellow water (urine) in rural area, anaerobic co-digestion of BW with agricultural waste is a promising and effective method for rural waste treatment and resource recovery. The purpose of this study was to investigate the performance of different agricultural wastes (peanut straw (PST), peanut shell (PSH), swine wastewater acting as co-substrate for anaerobic co-digestion with BW, and the relative mechanisms were explored. When the mixed ratio was uniformly set as 1:1 (mass ratio, measured by volatile solid (VS)) and initial VS load as 20 g/L, the maximum cumulative methane production obtained by co-digestion (21 days) of BW and PST was 688 mL/g-VS, which performed better than the individual substrates (341 mL/g-VS), as well as the average of the sole BW and sole PST groups (531.2 mL/g-VS). The most impactful advantage was ascribed to the promotion of hydrolytic and acidogenic enzyme activities. The addition of PST also reduced the production of endogenous humus, which is difficult for biodegradation. Microbial community analysis showed that different co-substrates would affect the microbial community composition in the reactor. The relative abundance of hydrolytic acidogens in the PST and PSH co-digestion groups were higher than that in the SW co-digestion and sole BW groups, and the methanogenic archaea were dominated by the acetate-trophic Methanotrichaceae. The overall results suggest that anaerobic co-digestion is a feasible method, and co-digestion of BW and PST can improve methane production potential.

Effects of Straw Returning and Biochar Addition on Greenhouse Gas Emissions from High Nitrate Nitrogen Soil After Flooding in Rice-vegetable Rotation System in Tropical China

In rice-vegetable rotation systems in tropical areas, a large amount of nitrate nitrogen accumulates after fertilization in the melon and vegetable season, which leads to the leaching of nitrate nitrogen and a large amount of N2O emission after the seasonal flooding of rice, which leads to nitrogen loss and intensification of the greenhouse effect. How to improve the utilization rate of nitrate nitrogen and reduce N2O emissions has become an urgent problem to be solved. Six treatments were set up [200 mg·kg-1 KNO3 (CK); 200 mg·kg-1 KNO3 + 2% biochar addition (B); 200 mg·kg-1 KNO3+1% peanut straw addition (P); 200 mg·kg-1 KNO3 + 2% biochar + 1% peanut straw addition (P+B); 200 mg·kg-1 KNO3 + 1% rice straw addition (R); 200 mg·kg-1 KNO3 + 2% biochar+1% rice straw addition (R+B)] and cultured at 25℃ for 114 d to explore the effects of organic material addition on greenhouse gas emissions and nitrogen use after flooding in high nitrate nitrogen soil. The results showed that compared with that in CK, adding straw or combining straw with biochar significantly increased soil pH (P<0.05). The B and P treatments significantly increased the cumulative N2O emissions by 41.6% and 28.5% (P<0.05), and the P+B, R, and R+B treatments significantly decreased the cumulative N2O emissions by 14.1%, 24.7%, and 36.7% (P<0.05), respectively. The addition of straw increased the net warming potential of greenhouse gases (NGWP). The addition of coir biochar significantly reduced the effect of straw on NGWP (P<0.05). The combined application of straw and biochar decreased NGWP, and P+B significantly decreased NGWP, but that with R+B was not significant (P>0.05). Adding straw or biochar significantly increased soil microbial biomass carbon (MBC) (P<0.05), and that of P+B was the highest (502.26 mg·kg-1). The combined application of straw and biochar increased soil microbial biomass nitrogen (MBN), and that of P+B was the highest. The N2O emission flux was negatively correlated with pH (P<0.01) and positively correlated with NH4+-N and NO3--N (P<0.01). The cumulative emission of N2O was negatively correlated with MBN (P<0.05). There was a significant negative correlation between NO3--N and MBN (P<0.01), indicating that the reduction in NO3--N was likely to be held by microorganisms, and the increase in the microbial hold of NO3--N also reduced N2O emission. In conclusion, the combined application of peanut straw and coconut shell biochar could significantly inhibit N2O emission and increase soil MBC and MBN, which is a reasonable measure to make full use of nitrogen fertilizer, reduce nitrogen loss, and slow down N2O emission after the season of Hainan vegetables.

Catalytic hydrotreating of crude bio-oil from straw and its distillates obtained by molecular distillation: A comparative study

In this study, the crude bio-oil (CBO) obtained from hydrothermal liquefaction of peanut straw was separated into light oil (LO) and heavy oil (HO) by molecular distillation at 130 ℃ and different pressures (0.5, 1 and 3 kPa). With process variables fixed, the CBO and its distillates were subjected to catalytic hydrotreating to probe the behavior characteristics of CBO from straws during this process. The LO yield fluctuated between 29.8 and 34.8 wt% with the change of distillation pressure. LO presented lower C content and higher H and O content than the corresponding HO. The LO obtained at 1 kPa showed a significant content difference between ketones (34.50%) and phenolic compounds (5.84%), indicating the differential distribution of these chemical components in CBO and the possibility of component separation by molecular distillation. Hydrotreating of LO gained obviously higher yield of upgraded oil (82.1–89.7 wt%) and lower yield of solid (6.1–9.1 wt%) than the corresponding HO (61.2–69.4 wt% and 21.3–24.6 wt%, respectively). The addition of n-hexane in the hydrotreating of HO led to an increase in hydrocarbon content and a decrease in content of phenolic compounds in the upgraded oil, although it did not contribute to increasing the upgraded oil yield.

The Inhibiting Effects of High-Dose Biochar Application on Soil Microbial Metagenomics and Rice (Oryza sativa L.) Production.

Biochar is usually considered as an organic improver which can improve soil and increase crop yields. However, the unrestricted application of biochar to normal-fertility farmland will cause chemical stress on crops and affect agricultural production. At present, the effects and mechanisms of high-dose applications of biochar on rice (Oryza sativa L.) production and soil biological characteristics have not been fully studied. In this greenhouse pot experiment, combined with soil microbial metagenomics, three treatments in triplicates were conducted to explore the responses of rice production, soil chemical properties, and soil biological properties to high-dose applications of biochar (5%, w/w) prepared using peanut waste (peanut hulls and straw). The results show that peanut hulls, with a loose texture and pore structure, are a raw material with stronger effects for preparing biochar than peanut straw in terms of its physical structure. In a rice monoculture system, high-dose applications of biochar (5%, w/w) can slightly increase the grains per spike, while significantly inhibiting the spike number per pot and the percentage of setting. High-dose applications of biochar also have significant negative effects on the diversity and stability of soil bacterial and archaeal communities. Moreover, the microbial metabolism and nutrient cycling processes are also significantly affected by changing the soil carbon/nitrogen ratio. This study discusses the response mechanisms of rice production and soil biology to high-dose biochar applications, and complements the understanding of irrational biochar application on agricultural production and land sustainability.

Biochemical Characterization of Novel GH6 Endoglucanase from Myxococcus sp. B6-1 and Its Effects on Agricultural Straws Saccharification.

Cellulase has been widely used in many industrial fields, such as feed and food industry, because it can hydrolyze cellulose to oligosaccharides with a lower degree of polymerization. Endo-β-1,4-glucanase is a critical speed-limiting cellulase in the saccharification process. In this study, endo-β-1,4-glucanase gene (CelA257) from Myxococcus sp. B6-1 was cloned and expressed in Escherichia coli. CelA257 contained carbohydrate-binding module (CBM) 4-9 and glycosyl hydrolase (GH) family 6 domain that shares 54.7% identity with endoglucanase from Streptomyces halstedii. The recombinant enzyme exhibited optimal activity at pH 6.5 and 50 °C and was stable over a broad pH (6-9.5) range and temperature < 50 °C. CelA257 exhibited broad substrate specificity to barley β-glucan, lichenin, CMC, chitosan, laminarin, avicel, and phosphoric acid swollen cellulose (PASC). CelA257 degraded both cellotetrose (G4) and cellppentaose (G5) to cellobiose (G2) and cellotriose (G3). Adding CelA257 increased the release of reducing sugars in crop straw powers, including wheat straw (0.18 mg/mL), rape straw (0.42 mg/mL), rice straw (0.16 mg/mL), peanut straw (0.16 mg/mL), and corn straw (0.61 mg/mL). This study provides a potential additive in biomass saccharification applications.

Mycorrhiza-inoculated biochar as an eco-friendly tool improves the broomrape control efficacy in two faba bean cultivars

Since broomrape weed has an intricate life cycle, its completely elimination is almost impossible. However, it is necessary to try to obtain modern means to reduce broomrape damage. Till now there is no effective methods can be used to reduce the broomrape seed bank in soil. Despite the documented favorable results of its role in amending several issues of the agricultural lands, the available knowledges related to the importance of biochar to protect faba bean from broomrape attacks are rare. Thus, the present work strived to find out the role of biochar alone or combined with mycorrhiza as novel and applicable practices to quench the attacks of broomrape against faba bean plants. A two-year field trail was implemented in broomrape-infested field. The experimental units of two cultivars (Sakha-1 and Misr-3) of faba bean were treated by mycorrhiza (VAM), rice biochar + VAM, peanut biochar + VAM, and glyphosate, in addition to the control treatment (weedy check). Findings clarified that broomrape spikes number and weight and number of faba bean infected plants were higher with Sakha-1 than Misr-3. Among the biochar types and cultivars, VAM inoculation was more effective with peanut straw biochar + VAM for MIsr-3. The distinctive reductions in almost broomrape parameters were obtained with VAM and peanut biochar + VAM equaling the recommended practice (glyphosate). Sakha-1 or Misr-3 plants treated with VAM, rice biochar + VAM and peanut biochar + VAM possessed distinctive improvements in pods weight, seed yield and of 100-seed weight of faba bean equaling glyphosate treatment. It could be concluded that VAM alone or with biochar raised the tolerance degree of faba bean genotype against broomrape attacks, hence sustaining the productivity, could be achieved through application of biochar inoculated with mycorrhiza. Despite the differences between mycorrhiza-inoculated biochar and glyphosate in broomrape traits and faba bean yield were not significant, the application of inoculated biochar as an eco-friendly tool is advisable for sustaining faba bean cultivation.

Impact of different dietary fibre sources on production performance, bacterial composition and metabolites in the caecal contents of rabbits.

This study was conducted to investigate the effects of different dietary fibre sources on growth performance, gastrointestinal tract development, caecal fermentation and bacterial composition in the caecal contents of rabbits. A total of 120 35-day-old weaned Minxinan black rabbits were divided into three groups and fed a diet composed of peanut straw powder (Group A), alfalfa powder (Group B) and soybean straw powder (Group C) as the main fibre source. The final body weight and average daily gainin Group B were higher than those in Group C, and the average daily feed intakeand feed conversion ratio in Group A were lower than those in Group C (p < 0.05). The relative weights of the stomach, small intestine and caecum of rabbits in Group C were higher than those in Groups of B and A, and the relative weights of the caecal contents in Group C were lower than those in Groups A or B (p < 0.05). The pH value and propionic acid, butyric acid and valeric acid concentrations in the caecum of Group C were lower than those in the caecum of Groups A orB, and the concentration of acetic acid in the caecum was lower (p < 0.05). The dominant microbes in the caecal contents of Minxinan black rabbits were Firmicutes, Bacteroidetes and Proteobacteria at the phylum level, and the number of species, Chao1 index and ACE index measured was different between the B-C and A-C groups (p < 0.05). Different dietary fibre sources could affect the growth performance, gastrointestinal tract development and intestinal microbiota of rabbits, and the nutritional value of alfalfa powder was better than that of peanut straw and soybean straw.

Pelatihan Pembuatan Pakan Ternak Sapi Fermentasi Berbasis Limbah Pertanian

The service activity with the title Training on Making Fermented Cattle Feed Based on Agricultural Waste aims to increase the competence of breeders in processing feed ingredients to become of higher quality and produce feed based on agricultural waste as an alternative to forage substitute feed. This activity was carried out through several stages, namely: Introduction of feed ingredients (Aspects of scientific theory), Training on Agricultural Waste-Based Fermentation Processing, and Harvesting-Giving Livestock. The method applied is Participatory Rural Appraisal (PRA). This method provides an opportunity for partners to be able to observe, study, share, improve and analyze knowledge about the conditions of farmers in processing quality local raw materials. PRA is substantially a method to find out the potential and problems of partners and provide solutions to solve various problems found. Based on the results of the activity, it was found that the potential for agricultural waste that could be used as animal feed at partner locations included: rice straw, peanut straw, and corn buns. These three types in principle can complement each other's nutritional needs, especially if they are used as substitute feed. The conclusion that can be drawn from this activity is that the utilization of the three identified types of waste can be used as cattle feed which can be processed through mechanical (physical) and biological treatment through fermentation techniques. The evaluation results obtained are in a position at 90.57.

Dissolved biochar fractions and solid biochar particles inhibit soil acidification induced by nitrification through different mechanisms

Biochar can inhibit soil acidification by decreasing the H+ input from nitrification and improving soil pH buffering capacity (pHBC). However, biochar is a complex material and the roles of its different components in inhibiting soil acidification induced by nitrification remain unclear. To address this knowledge gap, dissolved biochar fractions (DBC) and solid biochar particles (SBC) were separated and mixed thoroughly with an amended Ultisol. Following a urea addition, the soils were subjected to an incubation study. The results showed that both the DBC and SBC inhibited soil acidification by nitrification. The DBC inhibited soil acidification by decreasing the H+ input from nitrification, while SBC enhanced the soil pHBC. The DBC from peanut straw biochar (PBC) and rice straw biochar (RBC) decreased the H+ release by 16 % and 18 % at the end of incubation. The decrease in H+ release was attributed to the inhibition of soil nitrification and net mineralization caused by the toxicity of the phenols in DBC to soil bacteria. The abundance of ammonia-oxidizing bacteria (AOB) and total bacteria decreased by >60 % in the treatments with DBC. The opposite effects were observed in the treatments with SBC. Soil pHBC increased by 7 % and 19 % after the application of solid RBC and PBC particles, respectively. The abundance of carboxyl on the surface of SBC was mainly responsible for the increase in soil pHBC. Generally, the mixed application of DBC and SBC was more effective at inhibiting soil acidification than their individual applications. The negative impacts of dissolved biochar components on soil microorganisms need to be closely monitored.

Activating soil nitrification by co-application of peanut straw biochar and organic fertilizer in a rare earth mining soil

The intensive mining activities to extract rare earth elements from ion-adsorption rare earth deposits have introduced massive amounts of ammonium into the tailing soils in southern China. Compared to the ubiquitous soil nitrification in cropland, forest, and grassland soils, however, there is no feasible strategy to alleviate the ammonium contamination in tailing soil. Herein, the feasibility to remove ammonium by adding ammonium adsorbents (e.g., biochar, activated carbon, and zeolite), alkaline materials, and organic fertilizer to the rare earth mining soil was explored. The amendment of rice straw biochar, activated carbon, or zeolite in combination with CaCO3 and organic fertilizer showed no significant effect on ammonium removal due to their limited capacity to elevate soil pH. However, the co-application of peanut straw biochar (PSBC), CaCO3, and organic fertilizer activated both the ammonia volatilization and soil nitrification processes. Specifically, the three components functioned as follows: organic fertilizer supplied active ammonia-oxidizing bacteria (AOB); PSBC stimulated AOB proliferation by elevating soil pH above 7.75; CaCO3 ameliorated soil acidity and reduced the lag time for activating soil nitrification. The soil ammonium removal and nitrate accumulation rates were positively correlated to the acid neutralization capacity of PSBC prepared at 400 °C–800 °C. The qPCR and microbial community analysis results indicated that Nitrosomonas europaea was the dominant AOB that was responsible for enhanced soil nitrification. Our findings pave the way for developing cost-effective strategies to remediate ammonium contamination in rare earth mining soils.

Design and Testing of the Peanut Pod Cleaning Device

Due to the design of peanut harvesters and cleaners, peanut pods are often mixed with soil, gravel, peanut straw, and other impurities. To solve this problem, this study focused on designing a peanut pod cleaning device by integrating a negative pressure centrifugal fan, a hydrometric cleaning sieve, and a reversible long-mesh cleaning sieve. The relative motion of the peanut pod on the sieve was discussed, its stress analyzed, the design parameters of the sieve and fan determined, and the operation of the device was monitored by using sensors, which accurately recorded and adjusted the working parameters. Finally, the key parameters were tested, and the results showed that the design requirements were met at a vibration frequency of 5.5 Hz, a hydrometric cleaning sieve inclination of 15°, a reciprocating long mesh cleaning sieve inclination of 5°, and a fan speed of 1500 rev/min; the mean loss is 2.26%, and the mean impurity is 3.18%. The findings can be used to provide technical support and reference for the development of peanut pod cleaning devices.

Dietary inclusion of fermented ginger straw effect on the growth performance, gastrointestinal tract development and caecal fermentation of fattening rabbits

This experiment was conducted to evaluate the effects of dietary inclusion of fermented ginger straw on the growth performance, gastrointestinal tract development and caecal fermentation of fattening rabbits. A total of 160 45-d-old Laiwu black rabbits were randomly divided into 4 groups and fed 0% (Control), 5, 10 or 15% fermented ginger straw in their diet as a replacement for peanut straw powder. The trial lasted for 7 d of adaptation and 43 d for testing. Growth performance was recorded from 52 to 95 d of age (n=5 per treatment with 30 rabbits, 3 males and 3 females per replicate), TTAD of nutrients from 91 to 95 d of age, and gastrointestinal tract development, caecum fermentation and carcass traits were determined at 95 d of age (n=5 per treatment with 10 rabbits, 1 males and 1 females in per replicate).The results showed that the average daily gain and final body weight in the experimental groups (5, 10 and 15% fermented ginger straw) were higher than in the control group (P&lt;0.05). However, the average daily feed intake in the 15% group was higher than in the other groups, while the total tract apparent digestibility of crude protein, ether extract, neutral detergent fibre and acid detergent fibre were lower than in the control group (P&lt;0.05), and the relative weights of the stomach, small intestine and caecum content in the 15% substitution group were higher than those in the control group (P&lt;0.05). In addition, the thickness of the muscle layer in the 15% substitution group was higher than that in the other groups (P&lt;0.05). Moreover, pH and total volatile fatty acids concentration in the caecal content were similar among the 4 groups (P&gt;0.05). The current work shows that fermented ginger straw could be used as roughage material in fattening rabbit production up to a dietary dose of 10%.

A Nationwide Study of Residual Fate of Fluxapyroxad and Its Metabolites in Peanut Crops Across China: Assessment of Human Exposure Potential.

Elaborating on the residual fate of fluxapyroxad and its metabolites based on their nationwide application was vital to protect the human population from their hazardous effects. In this study, a rapid and sensitive analytical method was developed to trace fluxapyroxad and two of its metabolites in peanut matrices using an ultrahigh chromatography method coupled with mass spectrometry (UHPLC−MS/MS) within 3.5 min. The occurrence, pharmacokinetic degradation and terminal magnitudes of fluxapyroxad were reflected in the original deposition of 8.41−38.15 mg/kg, half−lives of 2.5−8.6 d and final concentrations of 0.004−37.38 mg/kg in peanut straw. The total concentrations of fluxapyroxad in peanut straw (0.04−39.28 mg/kg) were significantly higher than those in peanut kernels (<0.001−0.005 mg/kg) and an obvious concentration effect was observed in fresh (0.01−11.56 mg/kg) compared dried peanut straw (0.04−38.97 mg/kg). Fluxapyroxad was demethylated to 3−(difluoromethyl)−N−(3′,4′,5′−trifluoro[1,1′−biphenyl]−2−yl)−1H−pyrazole−4−carboxamide (M700F008, 0.02−5.69 mg/kg) and further N−glycosylated to 3−(difluoromethyl)−1−(ß−D−glucopyranosyl)−N−(3′,4′,5′−triflurobipheny−2−yl)−1H−pyrzaole−4−carboxamide (M700F048, 0.04−39.28 mg/kg).The risk quotients of the total fluxapyroxad for the urban groups were significantly higher than those for the rural groups, and were both negatively correlated with the age of the groups, although both acute (ARfD%, 0.006−0.012%) and chronic (ADI%, 0.415−1.289%) risks are acceptable for the human population. The high-potential health risks of fluxapyroxad should be continuously emphasized for susceptible toddlers (1−3 years), especially those residing in urban areas.

Long-term manure amendment reduces nitrous oxide emissions through decreasing the abundance ratio of amoA and nosZ genes in an Ultisol

Organic fertilizers are frequently applied to soils to improve soil multifunctionality and maintain crop productivity in agricultural practices. However, how organic fertilizations influence soil nitrous oxide (N2O) emissions remains ambiguous, especially considering their linkage with the abundance of nitrogen (N)-cycling microorganisms. Here, we conducted an incubation experiment to examine the effect of partial replacement of mineral fertilizers with organic fertilizers on the abundance of N-cycling functional genes and N2O emissions at 60 % and 100 % water-filled pore space (WFPS) in an acidic Ultisol. Soil samples were collected from 32-year fertilization trials, including four treatments of control (no fertilizer), mineral NPK fertilizer (NPK), NPK + Peanut Straw (NPKS), and NPK + Pig Manure (NPKM). The N2O emissions from soils incubated at 100 % WFPS were significantly higher than those at 60 % WFPS in all treatments. Compared with NPK, NPKS and NPKM reduced N2O emissions, with a more pronounced effect in NPKM. The N2O flux was positively associated with the abundance of AOA and AOB amoA genes, and the abundance ratio of amoA/nosZ (i.e., the ratio of AOA amoA plus AOB amoA and nosZ І plus nosZ ІІ) when the peak N2O flux appeared. Random forest analysis showed that the abundance ratio of amoA/nosZ was the best predictor for N2O emissions. Compared with NPK, NPKM increased soil pH but reduced the abundance ratio of amoA/nosZ, which might be the key factor in reducing N2O emissions. Together, our findings suggested that long-term manure application reduced N2O emissions by decreasing the abundance ratio of amoA/nosZ and provided novel insights into the impact of organic fertilizers on N2O emissions in acidic agricultural soils.

Nutrient recovery from biogas slurry via hydrothermal carbonization with different agricultural and forestry residue

Hydrothermal carbonization (HTC) of various agricultural and forestry waste (yellow bamboo, green bamboo, peanut shell, wood meal, peanut straw, wheat straw, rice husk, corn straw) with biogas slurry (BS) was studied, with the goal of recovering nutrients from BS. The ideal biomass material for nitrogen recovery was green bamboo, where 46.64 % of N was recovered after HTC at 250 °C for 3 h. The best one for phosphorus recovery was peanut straw, where P in liquid residue was not detectable post HTC. However, with all types of biomass tested, HTC failed recovering potassium from BS. Nitrogen recovery performance was positively correlated to the total cellulosic content of biomass as C-N active binding site for the formation of aliphatic amine were mainly provided by cellulose and hemicellulose. Increased metal salt concentration in biomass feedstock promoted phosphorus recovery as the mechanism was formation of metal phosphate precipitates. The hydrochars obtained from different biomass samples resulted in a wide range of pore sizes, which was critical for nutrient slow-release characteristics and plant growth promoting microorganism immobilization. Pot experiment further confirmed corn straw hydrochar had significant advantages over chemical fertilizer in water and nutrient retaining, which was critical for the enhancement of long-term soil fertility.

Kandungan nutrien, fraksi serat dan nutrient value fermentasi jerami kacang tanah (Arachys hypogaea) pada level nira lontar (Borassus flabellifer) yang berbeda

Objective: Peanut straw is abundantly available and still contains the nutrients needed by livestock but has high crude fiber content. Therefore, it is processed using fermentation technology using palm sap. The nutrient content and fiber fraction of fermented peanut shells at different levels of palm sap is the aim of the research. Methods: The Completely Randomized Design (CRD) used with 4 treatments and 6 replications, namely: JKT0 = peanut straw without palm sap, JKT5 = peanut straw + 5% palm sap, JKT10 = peanut straw + 10% palm sap, JKT15 = peanut straw + 15% palm sap and fermented for 21 days. The research variables were nutrient content resulted of proximate analysis, fiber fraction, and nutrient value . The analysis used one-way variance and Duncan's Multiple Range Test (DMRT). Results: Increasing the use of palm sap up to 15% in rice straw fermentation led to a 15.59% decrease in dry matter, a 7.33% increase in nitrogen-free extract (BETN), a 19.67% decrease in ash, an increase of up to 6.13% of NDF, a decrease of 6 .99% ADF, 7.57% decrease in cellulose, 45.45% increase in hemicellulose, nutrient value (DMI, DMD, and RFV) but no effect on crude protein, crude fiber, crude fat and lignin. and the use of 10% palm sap gives optimal results. Conclusions: The fermentation process using palm sap affects the dry matter content, BETN, ash, NDF, ADF, hemicellulose, cellulose, but has no impact on the content of crude protein, crude fiber, crude fat, and lignin and the best palm sap level is 10%.