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The acoustic diffusion equation model has been widely applied in various scenarios, but a larger prediction error exists when applied to underground spaces, showing a significantly lower characteristic of the sound pressure level in the later stage compared to field tests since underground spaces have a more closed acoustic environment. Therefore, we analyze the characteristics of underground spaces differentiating from aboveground spaces when applying the model and propose an improved model from the perspective of energy balance. The energy neglected in the calculation of the acoustic diffusion equation model is compensated in long channel underground spaces named "acoustic escape compensation". A simulation and two field experiments are conducted to verify the effectiveness of the proposed compensation strategy in long-channel underground spaces. The mean square error is used to evaluate the differences between the classical model and the improved model, which shows a numerical improvement of 1.3 in the underground field test. The results show that the improved model is more suitable for describing underground spaces. The proposed strategy provides an effective extension of the acoustic diffusion equation model to solve the problem of sound field prediction and management in underground spaces. [ABSTRACT FROM AUTHOR]

Affected by global warming, the frequency of crop pests and diseases have increased, causing huge losses to agricultural production. To better grasp the development and trends of research on the effects of climate change on crop pests and diseases, the literature on the impact of climate change on crop pests and diseases published from 1990 to 2021 in the Web of Science (WOS) core collection database was used. This study explores the literature characteristics and hotspot evolution through the bibliometric visualization analysis software COOC, VOSviewer, and CiteSpace, with a view to identifying the changing characteristics and trends of research changes in this field. The results showed that the number of literature on the impact of climate change on crop pests and diseases increased rapidly. The main fields involved include environmental sciences, ecology, and agronomy. Papers in these fields mainly published in journals, such as PLos One, Forest Ecology and Management, and Frontiers in Plant Science. The country with the highest number of publications was the United States, followed by China and Australia. The most prolific authors in the top 20 are research scholars from China. The first author of the top 20 highly cited papers was from the United States. It was found that that current research on the impact of climate change on crop pests and diseases mainly focuses on agricultural production and food safety. Modelling and crop growth has maintained steady development. At present, research in this field mainly focuses on pest management strategies under the impact of climate change, the response of single species, and the complex ecological mechanisms behind the response. This study provides unique insights into the research field of the impact of climate change on crop pests and diseases and provides a reference direction for future research development in this field. [ABSTRACT FROM AUTHOR]

Panax notoginseng is a highly regarded medicinal plant that has obstacles associated with continuous cropping. Understanding soil microorganisms is crucial, as they play a major role in this regard. However, soil microorganisms are affected by multiple factors; therefore, we need to conduct more in-depth research. This study investigated the combined effects of irrigation and microbial fertilizer treatments (J1F1, J1F2, J2F1, J2F2, J3F1, J3F2, and CK) on the diversity of bacterial and fungal microbial communities in the rhizosphere of Panax notoginseng. The bacterial 16S rRNA genes and fungal internal transcribed spacer (ITS) sequences were sequenced using Illumina HiSeq. The results showed that, without microbial fertilizer (CK), the microbial community abundance and diversity were significantly lower than in the other treatments; moreover, among the microbial fertilizer treatments, the microbial abundance in F1 was higher than that in F2. Under the same microbial fertilizer application, the incidence rate of Panax notoginseng root rot was J2 > J1 > J3, and the yield of Panax notoginseng was J3 > J2 > J1. Under the same irrigation conditions, the incidence rate of Panax notoginseng root rot was F1 > F2, and the yield of Panax notoginseng was F2 > F1. This study provides important guidance for Panax notoginseng plant microbiota and sustainable agriculture. [ABSTRACT FROM AUTHOR]

In response to global climate change, China has committed to peaking carbon emissions by 2030 and achieving carbon neutrality by 2060, commonly known as the "30–60 Dual Carbon". Under the background of "30–60 Dual Carbon", this article takes the electric power industry, which is the main industry contributing to China's carbon emission, as the research object, explores the time and peak value of the carbon peak of the electric power industry, and analyzes whether carbon neutrality can be realized under the peak method, so as to get the carbon neutrality path of the electric power industry and serve as the theoretical basis for the formulation of relevant policies. The Environmental Kuznets Curve inspection and the relationship analysis are carried out, then the system dynamics model is constructed, the carbon emissions from 2020 to 2040 are simulated, and the peak time is predicted. Three different scenarios are set to explore the path of electricity carbon neutralization under the premise of a fixed peak. It is shown that Gross Domestic Product per capita index factors have the largest positive contribution, and thermal power share index factors have the largest negative contribution to electricity carbon emissions. Based on the current efforts of the new policy, carbon emissions can achieve the peak carbon emissions' target before 2030, and it is expected to peak in 2029, with a peak range of about 4.95 billion tons. After the power industry peaks in 2029, i.e., Scenario 3, from coal 44%, gas 9% (2029) to coal 15%, gas 7% (2060), where the CCUS technology is widely used, this scenario can achieve carbon neutrality in electricity by 2060. Adjusting the power supply structure, strictly controlling the proportion of thermal power, optimizing the industrial structure, and popularization of carbon capture, utilization, and storage technology will all contribute to the "dual carbon" target of the power sector. [ABSTRACT FROM AUTHOR]

Jatropha curcas L. is a promising bioenergy source, and its seedling stage is sensitive to salinity. Nitrogen application presents an effective strategy for alleviating the adverse consequences of salinity stress. However, the responses of plant growth and physiology of Jatropha curcas L. seedlings to nitrogen application under salinity stress remain unclear. As a result, a one-year greenhouse plot experiment was conducted to investigate the effects of nitrogen application on the plant growth, antioxidant enzyme activity, and photosynthesis of Jatropha curcas L. seedlings under saline conditions. Experiment treatments consisted of three salinity stresses (mild salinity stress, S1: 2 g/kg; moderate salinity stress, S2: 4 g/kg; and severe salinity stress, S3: 6 g/kg), four nitrogen application rates (N0: 0 gN/plant; N1: 20 gN/plant; N2: 60 gN/plant; and N3: 100 gN/plant), and a control treatment (CK) which was without salinity stress and nitrogen application. The results showed that salinity stress substantially reduced plant growth of Jatropha curcas L. seedlings. As the salinity stress increased, the reduction in plant growth also increased. The S3 treatment had the lowest leaf area, leaf biomass, and total biomass, which decreased by an average of 70.4%, 66.3%, and 69.9%, respectively, compared to CK. Nitrogen application could compensate for these impairments of plant growth from salinity stress by promoting antioxidant enzyme activity and photosynthesis. As for mild and moderate salinity stresses, the maximum plant growth was found in the N3 treatment, with the maximum antioxidant enzyme activity, photosynthetic pigment, photosynthetic characteristic, and chlorophyll fluorescence. As for severe salinity stress, higher plant growth was found in N2 and N3 treatments, and there were no significant differences between N2 and N3 treatments. It also should be noted that the maximum photosynthetic characteristic and chlorophyll fluorescence were found in N2 treatment under severe salinity stress. In conclusion, nitrogen application could be an alternative strategy to improve the salinity tolerance of Jatropha curcas L. growth. The nitrogen application rate of 100 gN/plant could be recommended for low and moderate salinity stresses, while 60 gN/plant could be recommended for severe salinity stress. However, higher nitrogen application rate (>100 gN/plant) under mild and moderate salinity stress and the effects of reactive oxygen species under salinity stress should be further evaluated. [ABSTRACT FROM AUTHOR]

Plant-derived selenium is an important source of selenium (Se) for humans, which, however, has been restricted by a low content of Se in soil. Traditional Se fertilizers have tended to result in low selenium utilization. Thus, it was necessary to develop a new slow-release material to control Se fertilizer release. In this study, biochar pyrolyzed at 300 °C and 800 °C was cross-linked with polyethyleneimine (PEI) after being treated with HNO3 or NaOH (which were labeled Acid-W300, Acid-W800, Alkali-W300, and Alkali-W800). The results showed that the maximum adsorption capacities of Acid-W300, Alkali-W300, Acid-W800, and Alkali-W800 were 329.16 mg/g, 321.93 mg/g, 315.04 mg/g, and 344.33 mg/g, respectively. Among them, Acid-W800 and Alkali-W800 were mainly imine- and amide-bonded with SO32−, while Acid-W300 and Alkali-W300 were loaded with SO32− by forming the C–Se bonding as well as through imine- and amide-bonding. The release of four biochar-based selenium fertilizers in the red soil and brown soil extracts conformed to the pseudo-second-order kinetic model. The release rate and release amount of four biochar-based selenium fertilizers in the red soil extract were higher than those in the brown soil extract. Alkali-W800-Se had a higher proportion of Se-exchangeable release, accounting for 87.5% of the total loaded selenium, while Acid-W300-Se had the lowest proportion at 62.2%. However, the Se releases of Alkali-W800-Se were more than 42.49% and 37.67% of the total Se-loading capacity during 5 days of continuous red soil extraction and brown soil extraction, respectively. Acid-W300-Se released less than 20% of the total Se-loading capacity. Thus, Acid-W300-Se was the recommended slow-release Se fertilizer in red soil and brown soil. [ABSTRACT FROM AUTHOR]

Unconventional water resources (e.g., saline water, etc.) for irrigation as a promising supplementary water source can alleviate the freshwater shortage in the agriculture of red soil areas in Southern China. It should be noted that the presence of soluble salt in this water source may have detrimental influences on soil water infiltration and crop growth. Understanding the effect of unconventional water irrigation (UWI) on water infiltration in red soil is important. Previous studies have shown that the salinity of UWI can alter soil hydraulic properties to change soil water movement in saline soils. However, the underlying mechanism and factors of water infiltration in red soil under UWI with different salinity levels remain limited. Therefore, a laboratory experiment (one-dimensional vertical infiltration experiment and centrifuge method) was conducted to evaluate the effect of UWI with different salinity levels [0 (the distilled water, CK), 1 (S1), 2 (S2), 3 (S3), 5 (S5), and 10 (S10) g L−1] on the soil water infiltration process, soil water characteristic curve (SWCC), soil water constants estimated using the SWCC, saturated and unsaturated hydraulic conductivity (KS and K) as well as the soil chemistry of soil profile [pH, electrical conductivity (EC), and Na+ and Cl− contents]. The primary factors of soil water infiltration were identified using stepwise regression and path analysis methods. The results showed that UWI salinity decreased water infiltration by 1.53–7.99% at the end of infiltration in red soil, following the order of CK > S1 > S5 > S2 > S3 > S10. Moreover, UWI could enhance soil water availability with an increase of 8.55–12.68% in available water capacity. In contrast, lower KS and K were observed in S1–S10, and there was a negative linear relationship between irrigation salinity and KS. UWI also produced the EC, Na+, and Cl− accumulations in the soil profile. As the salinity level of UWI increased, the accumulations aggravated. Soil acidification was found in S1–S5, while soil alkalization was observed in S10. Additionally, α, PWP, and KS were the primary factors influencing the water infiltration of red soil. This study can help optimize the soil infiltration model under UWI and establish a foundation for unconventional water management in the red soil regions of Southern China and other similar regions. In addition, the undisturbed red soil under agricultural unconventional water irrigation and the long-term effect of unconventional water application should be considered. [ABSTRACT FROM AUTHOR]

Water scarcity poses a formidable challenge to agricultural productivity in arid regions, and water retention agents offer promising potential in this regard. Therefore, this study proposes developing and preparing polymers with water retention properties using waste green algae as raw material to explore the effectiveness of enhanced water infiltration and reduce evaporation at different use levels (0%, 0.15%, 0.30%, 0.45% and 0.60%) and maximum mixing depths (10 cm, 20 cm, 30 cm, 40 cm and 50 cm) and determine the optimum management. The results demonstrate that the synthesized polymers exhibited a remarkable swelling rate of 143.6 g/g, along with reusability and excellent temperature stability. The polymer application rate was positively correlated with infiltration duration, with an increase from 161 min to 750 min as the application rate rose from 0% to 0.60%. Concurrently, cumulative infiltration increased from 22.6 cm to 31.1 cm, showcasing the benefits of the polymer in enhancing water retention. Intriguingly, cumulative evapotranspiration initially decreased and then increased with increasing polymer application rates. Moreover, increasing the maximum mixing depth from 10 to 50 cm while maintaining the 0.3% application rate increased the cumulative infiltration (from 22.6 cm to 31.1 cm) and infiltration rate (from 0.03 cm/min to 0.08 cm/min) while decreasing the cumulative evaporation (from 44.4 mm to 31.7 mm). Considering the cumulative infiltration, infiltration rate and evapotranspiration characteristics, an optimized polymer application rate of 0.27% at a mixing depth of 0–50 cm was recommended for efficient soil moisture management. This study highlights the potential of green algae-derived biodegradable polymers as a win–win strategy for achieving waste alleviation of water scarcity in drylands, particularly for maize and wheat cultivation in northern China. [ABSTRACT FROM AUTHOR]

The fungal community structure and soil fertility in rhizosphere soil have an important effect on the health of Panax notoginseng (P. notoginseng). The attack of pathogenic fungi and the imbalance of soil fertility can easily lead to diseases. The effect of Bacillus subtilis on improving the community structure of soil fungi has been confirmed, and the corresponding biological agent products have been commercialized. A pot experiment carried out in a greenhouse explored the effect of a biological agent and fertilizer on the fungal community in the rhizosphere of P. notoginseng. In the experiment, fertilization and the addition of biological agents were set up with three gradients, respectively, and the full coupling experiment was adopted, and the blank control group (CK) was set up at the same time. Therefore, there were thirteen treatments in the experiment. NH4 decreased between 36.42% and 11.56%, AP increased between 6.03% and 92.46%, AK increased between 2.99% and 25.40%, TN increased between 0.10% and 9.41%, and TP increased by 18.25% to 47.73% The addition of Bacillus subtilis biological agent decreased the Chao1, Shannon, Simpson, and ACE index of fungi in the rhizosphere soil of P. notoginseng. The Chao1 index decreased between 0.39% and 78.22%; the ACE index decreased between 0.43% and 78.24%. The main pathogenic fungi Cylindrocarpon and Fusarium of P. notoginseng were different in the experimental results. Cylindrocarpon decreased under F1C1, F2C1, and F3C2 treatments, while Fusarium increased under F1C1, F2C2, F3C1, and F3C3 treatments and decreased Fusarium content in rhizosphere soil of P. notoginseng in other treatments. RDA analysis (Redundancy analysis) showed that NH4-N was negatively correlated with the main pathogen Cylindrocarpon, Fusarium, and Ilyonectria, while AP and AK were positively correlated with Cylindrocarpon, Fusarium, and Ilyonectria. The results of the GRA-TOPSIS analysis showed that the score of F3C2 was the highest, while F2C3 and F2C1 ranked second and third, respectively. The calculation results of the theoretical model based on GRA-TOPSIS analysis showed that the GRA-TOPSIS score was highest when the theoretical optimal fertilizer application rate and bacteria application rate were 116.31 kg hm−2 and 15.83 kg hm−2, respectively. [ABSTRACT FROM AUTHOR]

Vertical agriculture has developed rapidly in recent years, pushing artificial light planting to new heights. Under indoor artificial light, the light supply mode has practical significance in studying the impact of lighting conditions on plants. This experiment involved five intermittent light supply modes (with a light period of 16 h and a dark period of 8 h (16/8) as the control group, with a light period of 8 h and a dark period of 4 h repeated twice a day (8/4), a light period of 4 h and a dark period of 2 h repeated four times a day (4/2), a light period of 2 h and a dark period of 1 h repeated eight times a day (2/1), and a light period of 1 h and a dark period of 0.5 h repeated 16 times a day (1/0.5) (as the experimental groups). A total of ten treatments were combined before the continuous light supply mode (B) and after the continuous light supply mode (A). Through experimental settings, we explored the response mechanisms to intermittent and continuous light supply modes as they pertain to lettuce growth, nutrient content, photosynthetic parameters, and light stress. Through research, it was found that continuous light supply significantly increased plant height, root length, aboveground dry and fresh weight, and the underground dry and fresh weight of lettuce. The treatments with a light period 4 h/dark period 2 h (4/2) and a light period 8 h/dark period 4 h (8/4) significantly increased the N, P, K, and Cu contents. Additionally, continuous light supply helped stabilize the Mg, Ca, and Mn contents across all treatment groups. Stomatal closure has been found to cause a decrease in the rate of net photosynthesis, transpiration, and intercellular CO2 concentration. The energy absorbed by antenna pigments is significantly increased when participating in photochemical reactions; however, continuous light supply has been observed to reduce the absorption flux per reaction center (ABS/RC), trapped energy flux per reaction center (TR0/RC), electron transport flux per reaction center (ET0/RC), and the probability that a trapped exciton moves an electron into the electron transport chain beyond QA− (at t = 0) (ET0/TR0). Conversely, the electron transport flux per cross section (ET0/CS) has been found to increase significantly. In summary, among the intermittent light supply treatment groups, the 2/1 treatment group showed the best response to growth indicators, nutrient absorption, and photosynthesis, and could improve the quality of lettuce without adding additional light energy. Continuous light supply in the short term can improve the growth and nutrient absorption of lettuce; both of the two light supply modes produced light stress on lettuce, and this light stress caused by non-circadian rhythm forced the lettuce to increase its photochemical quenching (qI) and electro transport flux crossover (ET0/CS). This paper may provide a theoretical reference for the use of light supply modes in plant factories to improve vegetable yield, and for the study of the response mechanism of light stress under non-circadian rhythm. [ABSTRACT FROM AUTHOR]

Rapeseed is one of China's major oil crops, and accurate yield forecasting is crucial to the growth of the rapeseed industry and the country's food security. In this study, the data on natural and socio-economic factors from 2001 to 2020 and the yield of rapeseed in China were used as the data basis. The Pearson correlation coefficient was used to analyze the relationship between the influencing factors and the yield of rapeseed, and the prediction effect of four machine learning models (linear regression (LR), decision tree (DTR), random forest (RF), and support vector machine (SVM)) on the yield of rapeseed was compared in China's main rapeseed-producing area. The results demonstrate that the yield of rapeseed in China showed an increasing trend, but fluctuated greatly. Rural electricity consumption, gross agricultural production, the net amount of agricultural fertilizer application, effective irrigation area, total power of agricultural machinery, and consumption of agricultural plastic film had a positive effect on the increase in rapeseed yield. However, due to the impact of climate change and disasters, the yield of rapeseed has had significant fluctuations. A Pearson correlation analysis showed that socio-economic factors (rural electricity consumption, gross agricultural production, effective irrigation area, total power of agricultural machinery, consumption of agricultural plastic film, etc.) played a dominant role in rapeseed yield changes. The RF model had a good prediction effect on rapeseed yield, and natural factors and socio-economic factors had different effects on spring rapeseed and winter rapeseed. Winter rapeseed yield was mainly affected by socio-economic factors, accounting for as high as 89% of the importance. Among them, the sown area of rapeseed and the effective irrigation area had the greatest impact. The effects of natural factors and socio-economic factors on spring rapeseed yield were similar, accounting for 47% and 53%, respectively, and the mean annual precipitation, sunshine duration, and sown area of rapeseed were the most influential variables. [ABSTRACT FROM AUTHOR]

The cultivation of Panax notoginseng has been plagued by a multitude of challenges, including recurrent diseases, suboptimal value, inadequate quality, and environmental degradation resulting from improper water and fertilizer management. To address these issues and improve the yield of P. notoginseng and its saponin content, this study endeavors to identify the optimal irrigation and fertilization levels in shaded environments in Yunnan Province in Southwest China. In this field experiment, three-year-old plants were tested to evaluate the effects of water, soluble organic fertilizers, and their combinations on plant growth, physiological parameters, yield, and saponin content. The experiment included 12 treatments with three types of irrigation (10 (W1), 15 (W2), and 20 (W3) mm), totaling 440, 660, and 880 mm, and four levels of the total amount of fertilization (F1 (60, total N 12.6, total P 5.5, and total K 10.5 kg ha−1), F2 (90, total N 18.9, total P 8.3, and total K 15.7 kg ha−1), F3 (120, total N 25.2, total P 11.0, and total K 20.9 kg ha−1), F4 (150, total N 31.5, total P 13.8, and total K 26.1 kg ha−1)). The randomized complete block design was used, with 36 plots in total and 3 replications. The study utilized the TOPSIS method to determine the most effective water and fertilizer management strategy for the growth and production of P. notoginseng. The assessment of yield, water and fertilizer productivity, and saponin content across all treatments revealed that the W3F3 treatment resulted in significant increases in the plant's height, stem diameter, and net photosynthetic rate. Meanwhile, the W2F3 treatment exhibited the best root morphological traits. The W3F4 treatment effectively increased dry matter and transpiration. The combination of water and fertilization had a coupling effect that not only increased yield to 1400 kg ha−1 but also improved water–fertilizer productivity. The application of the W2F3 treatment resulted in a significant increase in the accumulation of active components, leading to a total P. notoginseng saponin (PNS) content of 24.94%. Moreover, the comprehensive index obtained through the TOPSIS model indicated that the W2F3 treatment outperformed other treatments. Therefore, this treatment can be considered a promising water and fertilizer model for P. notoginseng cultivation, which can enhance its yield, quality, and productivity while promoting sustainable green development. [ABSTRACT FROM AUTHOR]

Panax notoginseng is an important medicinal crop in China. The high incidence of root rot in P. notoginseng during the rainy season has restricted the development of the industry. It is believed that frequent rainfall and a warm soil environment are important factors that promote root rot incidence. However, there is still a significant knowledge gap in the relationship between rainfall and root rot incidence. To understand the effects of rainfall and fertilizer on root exudates, the soil bacterial structure, and root rot in P. notoginseng, four treatments were chosen for both field and pot experiments. These treatments included DW (rain shelter and no fertilizer), RW (no rain shelter and no fertilizer), DWF (rain shelter and fertilizer), and RWF (no rain shelter and fertilizer). The results showed that both factors (rain shelter and fertilizer) significantly affected root rot incidence and several other parameters. Among them, the effect of a rain shelter is more significant than that of fertilizer, and the combination of the two further improves the effect. DW and DWF treatments significantly reduced the soil moisture, phenolic acid, and root rot incidence, while significantly increasing the soil temperature and enzyme activities compared to RW or RWF. Seven phenolic acids secreted by P. notoginseng roots were all positively correlated with root rot incidence. Root rot was also positively correlated with Planctomycetota, Acidobacteriota, and Gemmatimonadota and negatively correlated with Firmicutes, Proteobacteria, Patescibacteria, and Nitrospirota. DWF treatment decreased the soil moisture and the concentration of p-hydroxybenzoic acid, syringic acid, phthalic acid, and vanillic acid and promoted the growth of Firmicutes and Proteobacteria, leading to the lowest incidence of root rot. [ABSTRACT FROM AUTHOR]

Excessive use of chemical fertilizers deteriorates the soil environment and limits the normal growth of Arabica coffee trees. In order to identify the optimal coupling mode of chemical fertilizer application and biomass return that enhances the soil ecological environment and promotes the photosynthetic efficiency of Arabica coffee, this study investigated the impacts of three levels of inorganic fertilizers (FL: 360 kg·ha−1, FM: 720 kg·ha−1, and FH: 1080 kg·ha−1) and three types of coffee husk returning methods (CB: coffee husk biochar, CC: coffee husk compost, CA: coffee husk ash) on the soil fertility, microbial amount, enzyme activity, and photosynthetic characteristics of the Arabica coffee root zone. The entropy weight-TOPSIS method was employed to evaluate the comprehensive benefits. The results showed that FM had the biggest effect on improving soil fertility, microorganisms, and enzyme activities compared with FL and FH. Moreover, compared to CA, CC significantly increased soil organic carbon, organic matter, and total nitrogen content. CC significantly enhanced the activities of soil phosphatase and urease, respectively, by 29.84% and 96.00%, and significantly increased the amount of bacteria, fungi, and actinomycetes by 62.15%, 68.42%, and 46.21%, respectively. The net photosynthetic rate (Pn), transpiration rate (Tr), and stomatal conductance (Gs) of FMCC were significantly higher than those of other treatments. The comprehensive benefit evaluation of the soil environment and photosynthetic characteristics by the entropy weight-TOPSIS method ranked FMCC first. Therefore, FMCC was the optimal coupling mode for fertilizer application and the coffee husk returning method. The findings of this study not only provide scientific guidance for fertilizing Arabica coffee but also clarify the proper approach to returning coffee husk to the field, thereby improving soil ecology and promoting green and efficient production of specialty crops. [ABSTRACT FROM AUTHOR]