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Abstract In this study, fast-growing poplar reclaimed from abandoned homestead in Xixian New District, Xi’an City, Shaanxi Province, was used as the research object to explore the multi-fractal characteristics of soil particle size distribution under different management modes of abandoned land (control), irrigation, fertilizer irrigation and mixed fertilizer irrigation. The results showed that the mean values of soil clay, silt and sand in abandoned land were 14.58%, 81.21% and 4.22% respectively, 14.08%, 79.92% and 5.99% under irrigation, 15.17%, 81.19% and 3.64% under fertilizer irrigation, and 16.75%, 80.20% and 3.05% in mixed fertilizer treatment. From 40 cm, with increasing soil depth, soil clay particles increase under irrigation, fertilizer irrigation, and mixed fertilizer irrigation modes. The single fractal dimension of soil particle size distribution (D) in each treatment ranges from 2.721 to 2.808. At 60–100 cm, D shows fertilizer irrigation > mixed fertilizer irrigation > irrigation > abandoned land, indicating that fertilization and irrigation can increase the fine-grained matter of deep soil particles and reduce soil roughness. Compared with abandoned land, under irrigation, fertilizer irrigation and mixed fertilizer modes the capacity dimension (D 0 ), entropy dimension (D 1 ), correlation dimension(D 2 ), shape characteristics of the multifractal spectrum (Δf) and overall inhomogeneity of the soil particle size distribution (D 0 –D 10 ) indicate an uneven distribution of soil particle size; fractal structure characteristics of soil (D −10 –D 0 ) indicate a simplified soil structure, and degree of dispersion of soil particle size distribution (D 1 /D 0 ) indicates that soil particle size is distributed in dense areas. Pearson correlation analysis showed that D was significantly correlated with clay, sand, D 0 –D 10 , soil organic matter (SOM) and soil available phosphorus (SAP) (P

To address the problems of salinization of the soil in gully control and land-making projects, the formation mechanism of soil interflow from a gully valley on the Loess Plateau was investigated, regarding its interface, water source, and spatial-temporal distribution characteristics, through field location monitoring and isotope tracer technique. The results showed the following: (1) there are two types of soil interflow in the Loess Plateau, namely soil interflow in slope and in gully, with interflow in gully being the main form; (2) adequate water supply, layered soil structure, and geographic disparity are conditions for the formation of soil interflow in the gully; (3) soil water is recharged by precipitation, surface water, and groundwater. Surface water is an important source of soil water recharge at the 0–100 cm depth, whereas groundwater is an important source of soil water recharge at the 100–200 cm depth. The results provide a basis for the regulation of the soil interflow, resource utilization, and land quality improvement in the Loess Plateau.

Abstract Background The silicified cell wall of diatoms, also known as frustule, shows huge potential as an outstanding bio-nanomaterial for hemostatic applications due to its high hemostatic efficiency, good biocompatibility, and ready availability. As the architectural features of the frustule determine its hemostatic performance, it is of great interest to develop an effective method to modify the frustule morphology into desired patterns to further improve hemostatic efficiency. Results In this study, the gene encoding Silicalemma Associated Protein 2 (a silicalemma-spanning protein) of Cyclotella cryptica (CcSAP2) was identified as a key gene in frustule morphogenesis. Thus, it was overexpressed and knocked down, respectively. The frustule of the overexpress lines showed no obvious alteration in morphology compared to the wild type (WT), while the size, specific surface area (BET), pore volume, and pore diameter of the knockdown strains changed greatly. Particularly, the knockdown frustules achieved a more pronounced coagulation effect and in vivo hemostatic performance than the WT strains. Such observations suggested that silicalemma proteins are ideal genetic encoding targets for manipulating frustule morphology associated hemostatic properties. Furthermore, the Mantel test was adopted to identify the key morphologies associated with C. cryptica bleeding control. Finally, based on our results and recent advances, the mechanism of frustule morphogenesis was discussed. Conclusion This study explores a new strategy for enhancing the hemostatic efficiency of the frustule based on genetic morphology modification and may provide insights into a better understanding of the frustule morphogenesis mechanism.

To investigate the contents of carbon, nitrogen, and phosphorus in tea plantation soils and their ecological stoichiometric characteristics, as well as their response to environmental factors in high-latitude regions of China, soil samples from 0 to 20 cm depth were collected from tea plantations at different altitudes and cultivation years in the main tea-producing areas of Shaanxi Province. These samples were used to determine the soil organic carbon (SOC), total nitrogen (TN), and total phosphorus (TP) contents and to calculate their stoichiometric ratios. The findings revealed the following: the average soil SOC and TN content in tea gardens were 13.15 and 1.30 g·kg−1, respectively, exceeding the national soil average. These values met the Class I tea garden fertility standards. However, the average soil TP content, at 0.45 g·kg−1, fell below the national soil average, meeting the Class II tea garden fertility standards. In tea gardens, the average ratios of carbon to nitrogen (C:N), carbon to phosphorus (C:P), and nitrogen to phosphorus (N:P) in the soil were 10.42, 30.98, and 3.32, respectively. These ratios were all lower than the national soil average, indicating relatively high phosphorus availability but nitrogen deficiency in tea garden soils. As altitude increased, there was a decline in soil SOC content, C N, and C P ratios, followed by a subsequent increase. No significant changes were seen in TN, TP, and N P ratio in the soil, but there was an increase in SOC content, TN content, and C P ratio during cultivation. The N-to-P ratio initially increased before decreasing, while the C-to-N ratio decreased before increasing. Soil TP content did not change significantly. The study recommends careful nitrogen fertilizer application in tea garden management to balance nitrogen and phosphorus.

In contrast to prolonged exposure to high temperatures, investigating short-term high-temperature stress can provide insights into the impact of varying heat stress durations on plant development and soil nutrient dynamics, which is crucial for advancing ecological agriculture. In this study, five heating temperatures were set at 200°C, 250°C, 300°C, 350°C, and 400°C, along with five heating time gradients of 6s, 10s, 14s, 18s, and 20s, including a control. A total of 26 treatment groups were analyzed, focusing on maize growth parameters and soil indicators. Principal component analysis was used for comprehensive evaluation. The results showed that high-temperature treatments with different heating times significantly influenced maize growth and soil properties. For instance, the treatment of 300°C+6s resulted in the longest total root length, while 200°C+6s led to the highest average root diameter. Plant height and leaf length were notably increased with the treatment of 400°C+6s. Most treatments resulted in decreased soil pH and organic matter content. Notably, the treatment of 350°C+16s showed the highest available phosphorus content, reaching 24.0 mg/kg, an increase of 4.5 mg/kg compared to the control. The study found that the average levels of active organic carbon and peroxidase were 1.26 mg/g and 3.91 mg/g, respectively. Additionally, the average mass fractions of clay, silt, and sand particles were 8.99%, 66.75%, and 24.26%, respectively. Through principal component analysis, six principal components were able to extract 19 indicators from the 26 treatments, covering 86.129% of the information. It was observed that 16 treatment methods performed better than the control in terms of soil comprehensive quality. The optimal treatment temperature and time identified for improving soil physicochemical properties and crop growth were 300°C+6s. These findings can be used to guide agricultural management and soil improvement practices, ultimately enhancing field productivity and providing valuable insights for sustainable agricultural development.

IntroductionThis article endeavors to investigate the influence of various fertilization methods on the characteristics of rhizosphere soil and organic carbon mineralization in the mixed soil of Mu Us Sandy land under maize cultivation, with the objective of laying the groundwork for low-carbon agriculture and the development of high-quality farmland.MethodsThe research focuses on soft rock and sand composite soil with a 1:2 ratio, and it comprises four treatments: no fertilization (CK), only chemical fertilization (CF), only cattle manure application (MF), and only oil residue application (DF).ResultsThe findings revealed that the use of organic fertilizer substantially elevated nutrient content and enzyme activity in the maize rhizosphere soil. Furthermore, it had a notable influence on both soil aggregate diameter and stability. Specifically, the DF treatment led to a significant increase in both soil aggregate diameter and stability. The mineralization rate of organic carbon in the maize rhizosphere soil could be categorized into two distinct phases: a rapid initial decline followed by a slower release. By the end of the incubation period, the cumulative mineralization of organic carbon in the MF, DF, and CF treatments showed a significant increase of 119.87%, 57.57%, and 24.15%, respectively, in comparison to the CK treatment. Additionally, the mineralization rate constants of the DF and MF treatments experienced a substantial rise, with increments of 23.52% and 45.97%, respectively, when contrasted with the CK treatment. The bacterial phyla Actinobacteriota, Proteobacteria, Chloroflexi, Acidobacteriota, and Firmicutes were dominant in the rhizosphere soil bacterial community. Specific genera such as Nocardioides and Sphingomonas showed significant correlations with organic carbon mineralization. The application of different organic fertilizer can improve soil physical, chemical and biological properties, and promote the mineralization process of organic carbon in maize rhizosphere soil.DiscussionNotably, the DF treatment exhibited the most favorable outcome, improving the overall quality of maize rhizosphere soil while incurring a minimal loss of unit organic carbon. These findings hold significant implications for optimizing field management practices and augmenting soil quality.

Abstract Background Pectus excavatum (PE) is the most common disease of chest wall deformity, with an incidence of 1 in 300—400 births. Nuss procedure has proved to be the best surgical treatment method and has been widely used after clinical use for 30 years. We aimed to review the clinical data of pectus excavatum (PE) of thoracoscopic Nuss procedure adopted the Modified bar bending method of the six-point seven-section type, and compare it with the traditional curved bar bending method to explore the clinical application effect. Methods Forty-six cases of clinical data were summarized of children with PE who adopted the treatment of the Modified bar bending method of the six-point seven-section type from January 2019 to December 2021, and 51 cases were compared of PE children who adopted the treatment of traditional curved bar bending method from January 2016 to December 2018, including the data of age, gender, preoperative symptoms, symmetry, Haller index, operation time, bar bending time, intraoperative bleeding, postoperative complications, bar migration, postoperative effect evaluation, etc. Results The Procedure duration (P = 0.008), bar bending time (P

IntroductionAgricultural eco-efficiency is an important index to evaluate the agricultural sustainable development and ecological economics, while simultaneously providing a metric for improvements to the rural environment and the stability of agricultural ecosystems.MethodsThis study took Anhui province as a case, and applied unit survey and list analysis methodologies to quantify rural agricultural non-point source pollution (NPS). Input-oriented super-efficient DEA-SBM was used to measure agricultural eco-efficiency in the typical North-South Transition Zone, and evaluated spatial correlations and differences.ResultsThis study showed that NPS was relatively stable, with less than 5% local variation in Chemical Oxygen Demand (COD), Total Nitrogen (TN), and Total Phosphorus (TP) pollutants. The environmental pressure caused by livestock breeding and the use of chemical fertilizers was very substantial, and the differences of rural agricultural NPS in Anhui Province had obvious north-south characteristics. The agricultural eco-efficiency exhibited an “inverted N” trend. Affected by the “Spatial proximity effect” and the “Matthew effect”, it presented spatial agglomeration and positive spatial correlation. The regional differences were significant, and the heterogeneity increased in our study areas. The southern region had the greatest variation, followed by the northern region, with the smallest variation in the central region, although inter-regional differences were consistent.DiscussionThough the rational allocation of resources, coordination between agricultural economic and environmental protection would be realized, and better conditions for the sustainable development of agricultural ecology and the long-term stability of agricultural ecosystem would be created.

Based on 295 capacity monitoring sites in Hanzhong city, we used partial least squares structural equation model to construct a model of the factors influencing cultivated land productivity using soil nutrients, farmland water resources, geological characteristics and soil properties as latent variables to explore the main factors affecting cultivated land productivity in Hanzhong city. The research results show that: (1) Soil nutrients, farmland water conservancy and soil properties were the main factors influencing cropland productivity, and had direct or indirect positive effects on cropland productivity, with the total effects ranging from soil properties (0.587) > farmland water conservancy (0.552) > soil nutrients (0.464). (2) Geological characteristics had no direct effect on cropland productivity, but indirectly influenced cropland productivity by affecting soil nutrients. (3) Slope had a negative effect on cropland productivity. Cultivated land productivity in Hanzhong city is influenced by various factors. Integrating the interactions and influence effects among the influencing factors, it is recommended to achieve coordinated and sustainable regional food production by improving water conservancy facilities, strengthening farmland quality, improving agricultural product quality, and building healthy capacity of cultivated land.

Soil aggregates are a crucial constituent of soil and have a significant function in regulating water, nutrients, air, and heat within the soil. The development of soil aggregates is influenced by various factors, including the soil’s parent material and human activities. Understanding the formation and the mechanism of stabilization of soil aggregates is of great significance in the study of soil development, in regulating and managing organic carbon pools in soils, and in promoting soil fertility. In this study, aeolian sandy soil with a low degree of soil development and compound soil formed by combining soft rock and aeolian sandy soil were selected as the research objects. We selected three time points from 0 to 9 years after amendment by soft rock in order to investigate the changes of soil aggregate cementing agents. The shape of soil aggregates in both types of soils was analyzed by environmental scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS), which were also used to assess the appearance of soil aggregates and quantify the composition of mineral elements on a cross section of the aggregate. The results show that when the soft rock and the aeolian sandy soil are compounded and mixed, the clay minerals in the soft rock change the microstructure of the original aeolian sandy soil from a single granular barrier to one characterized by a cumulative porous structure, indicating that clay minerals promote soil development and form aggregates with good structural properties. The cementing agents in the compounded soil aggregates are mainly clay minerals, aluminum, iron, and calcium. In comparison to aeolian sandy soils, the presence of iron and calcium in compounded soils is notably elevated. The iron oxides present in compounded soils serve a similar function to “bolts” in the formation of soil aggregates. These findings establish a theoretical foundation for investigating the process of soil aggregate formation and the mechanisms by which cementing agents contribute to their stabilization.

BackgroundAmbroxol is a widely used mucoactive drug in sputum clearance of respiratory diseases taken orally and by injection. However, there is a paucity of evidence for inhaled ambroxol in sputum clearance.MethodsThis study performed a multicenter, randomized, double-blind, placebo-controlled, phase 3 trial at 19 centers in China. Hospitalized adult patients with mucopurulent sputum and expectoration difficulty were recruited. Patients were randomized by 1:1 to receive inhalation of either ambroxol hydrochloride solution 3 mL (22.5 mg) + 0.9% sodium chloride 3 mL or 0.9% sodium chloride 6 mL twice daily for 5 days, with an interval of more than 6 h. The primary efficacy endpoint was the absolute change in the sputum property score after treatment compared to the baseline in the intention-to-treat population.ResultsBetween 10 April 2018 and 23 November 2020, 316 patients were recruited and assessed for eligibility, of whom 138 who received inhaled ambroxol and 134 who received a placebo were included. Patients who received inhaled ambroxol had a significantly greater decrease in the sputum property score compared with patients who received inhalation of placebo (difference: −0.29; 95% CI: −0.53 to −0.05; p = 0.0215). Compared with the placebo, inhaled ambroxol also significantly reduced more expectoration volume in 24 h (difference: −0.18; 95% CI: −0.34 to −0.03; p = 0.0166). There was no significant difference in the proportion of adverse events between the two groups, and no deaths were reported.DiscussionIn hospitalized adult patients with mucopurulent sputum and expectoration difficulty, inhaled ambroxol was safe and effective for sputum clearance compared with a placebo.Clinical trial registration[https://www.chictr.org.cn/showproj.html?proj=184677], Chinese Clinical Trial Registry [ChiCTR2200066348].

Due to high growth rate, outstanding abiotic stress tolerance, and rich value-added substances, Chrysotila roscoffensis, belonging to the phylum of Haptophyta, can be considered as a versatile resource for industrial exploitation of bioactive compounds. However, the application potential of C. roscoffensis has drawn attention until just recently, and the understanding related to the biological properties of this species is still scarce. For example, the sensitivities of C. roscoffensis to antibiotics, which is essential for the verification of heterotrophic capacity and the establishment of efficient genetic manipulation system is still unavailable. Aiming to provide fundamental information for future exploitation, the sensitivities of C. roscoffensis to nine types of antibiotics were tested in this study. The results demonstrated that C. roscoffensis exhibited relatively high resistances to ampicillin, kanamycin, streptomycin, gentamicin, and geneticin, while was sensitive to bleomycin, hygromycin B, paromomycin, and chloramphenicol. Using the former five types of antibiotics, a bacteria removal strategy was established tentatively. Finally, the axenicity of treated C. roscoffensis was confirmed based on a multi-strategy method including solid plate, 16S rDNA amplification, and nuclear acid staining. This report can provide valuable information for the development of optimal selection markers, which are meaningful for more extensive transgenic studies in C. roscoffensis. Moreover, our study also paves the way for the establishment of heterotrophic/mixotrophic cultivation modes of C. roscoffensis.

Nitrogen is one of the main pollution sources in aquaculture system. Microalgae are considered as one of the ideal bio-absorbents used in wastewater purification, due to their nitrogen removal capacity and more importantly nutritional value. Nannochloropsis oceanica, Cyclotella atomus, and Conticribra weissflogii are famous as diet microalgae. However, estimation of nitrogen removal capability and concomitant nutritional properties of the three species have been rarely reported, which was performed in this study. N. oceanica, C. atomus, and C. weissflogii were cultivated with two initial nitrate-N concentration, noted as NC (13.85 mg·L–1) and NW (5 mg·L–1) groups, respectively. All the three microalgal strains in NC group showed higher maximum cell density, specific growth rate, and biomass concentration, maximal quantum yield of PSII (Fv/Fm), total Chlorophyll and carotenoids contents than that in NW group. These results confirmed the importance of nitrogen for microalgal biomass generation and photosynthetic performance. From Fv/Fm, N. oceanica has better adaptability towards nitrogen depletion compared to other two selected strains. The three microalgae exhibited significantly stronger nitrate-N absorption efficiencies in NC group at the same timepoint, compared to NW. Analyzing the average amount of nitrate-N absorbed by each cell daily, C. weissflogii gained the largest value, followed successively by C. atomus and N. oceanica, likely due to species specificity. Moreover, three strains removed 90% of nitrate-N within five days and 99% of that within seven days, showing splendid nitrogen removal potentials. These results confirmed the feasibility of removing nitrogen from wastewater with the selected three microalgae. Nutritional properties of microalgal biomass were also investigated. For the three species, lower nitrate-N was beneficial for the production of soluble sugar, total lipid, and saturated fatty acid, while higher nitrate-N led to more soluble protein and polyunsaturated fatty acid. In summary, N. oceanica, C. atomus, and C. weissflogii all showed strong nitrogen removal capacity, whose growth characteristics and nutritional properties varied with nitrogen concentration. In practical application for assimilating nitrogen, these findings could provide some references for the selection of suitable microalgae species in order to satisfy different nutritional requirements of various aquatic animals.

Low/high temperature stress is one of the key abiotic factors restricting the implementation of microalgal large-scale production. Metabolism, involved in abiotic stress resistances, have been reported in plants, but the related research in microalgae is far behind. This study analyzed the transcriptional changes in Nannochloropsis oceanica under low and high temperature stresses by RNA-seq technology. Results indicated that the total differentially expressed gene (DEG) amount under high temperature stress was much more than low temperature stress. GO enrichment analysis suggested that DEGs under low temperature were mainly concentrated in protein modification and phosphorus metabolic process, while transmembrane transport, lipid localization and transport, and cellular homeostasis were the most enriched terms under high temperature. Moreover, “membrane” was the most enriched term in both low and high temperature groups. The gene expressions of 37 stress resistance-related enzymes/proteins (172 genes) were analyzed concretely in N. oceanica for the first time. Results revealed that ornithine decarboxylase (ODC) was significantly down-regulated, while choline dehydrogenase (CHDH), late embryogenesis abundant (LEA), dehydrin (DHN), chitinase (CHI), calmodulin (CaM), and lipid transfer protein (LTP) were extremely up-regulated under low temperature. Under high temperature, more genes with drastic changes were identified. Superoxide dismutase (SOD), ascorbate peroxidase (APX), glutathione synthetase (GSS), and glyoxalase II (Gly II) exhibited down-regulated significantly, while glutathione S-transferase (GST), CHDH, L-asparaginase (L-ASP), LEA, DHN, early response to dehydration protein (ERD), heat shock protein (HSP), and CaM were dramatically up-regulated. No significant changes were detected in glutathione peroxidase (GPX), tocopherol cyclase (TC), gamma-glutamylcysteine synthetase (γ-GCS), pyrroline‐5–carboxylate reductase (P5CR), asparagine synthetase (ASN ), succinate-semialdehyde dehydrogenase (SSADH), pyruvate decarboxylase (PDC), and S-adenosylmethionine synthetase (SAMS) under low or high temperature. Furthermore, 166 transcription factor (TF) genes related to plant stress resistance were characterized and categorized into 20 TF families. MYB was the most abundant and active one, revealing that the MYB family played a critical role of temperature resistance in N. oceanica. These new findings could benefit the understanding of the temperature resistance mechanism in Nannochloropsis. The significantly changed genes might be ideal candidates for breeding elite Nannochloropsis strains with stronger resistance to temperature stress using genetic engineering methods.

This study explored the profibrotic impact of high glucose in the lung and potential mechanisms using latent TGF-β1-induced human epithelial cell pulmonary fibrosis and bleomycin (BLM)-induced pulmonary fibrosis models. Results demonstrated that high glucose administration induced epithelial–mesenchymal transition (EMT) in human epithelial cells in a dose-dependent manner via activating latent TGF-β1, followed by increased expression of mesenchymal-related proteins and decreased expression of epithelial marker protein E-cadherin. Further mechanism analysis showed that administration of high glucose dose-dependently promoted total and mitochondrial reactive oxygen species (ROS) accumulation in human epithelial cells, which promoted latent TGF-β1 activation. However, N-acetyl-L-cysteine, a ROS eliminator, inhibited such effects. An in vivo feed study found that mice given a high-glucose diet had more seriously pathological characteristics of pulmonary fibrosis in BLM-treated mice, including increasing infiltrated inflammatory cells, collagen I deposition, and the expression of mesenchymal-related proteins while decreasing the expression of the epithelial marker E-cadherin. In addition, high glucose intake further increased TGF-β1 concentration and upregulated p-Smad2/3 and snail in lung tissues from BLM-treated mice when compared to BLM-treated mice. Finally, supplementation with high glucose further increased the production of lipid peroxidation metabolite malondialdehyde and decreased superoxide dismutase activity in BLM-treated mice. Collectively, these findings illustrate that high glucose supplementation activates a form of latent TGF-β1 by promoting ROS accumulation and ultimately exacerbates the development of pulmonary fibrosis.

Cultivated land is an important prerequisite and guarantee for food production and security, and the change of cultivated land resources in China has always been concerned. National land survey is an effective way to accurately grasp the area and distribution of cultivated land resources. However, due to the differences in technical means and statistical standards at different stages, there are obvious breakpoints among the cultivated land area data of the three land surveys in China, which hinders the in-depth study of the spatio-temporal distribution of cultivated land resources in long-time series. The Autoregressive Integrated Moving Average model is used to reconstruct and mine the cultivated land area data from 1996 to 2019 based on the data of the third land survey in China. The spatio-temporal variation characteristics of cultivated land area are explored by using Geographic Information System spatial analysis, and the driving factors of cultivated land change are analyzed based on Geographical Detector (GeoDetector) from the perspective of social, economic, agricultural and natural. The results show that the area of cultivated land in China decreased continuously from 1996 to 2019, with a sharp decrease from 1996 to 2004 and a slow decrease from 2005 to 2019. From 1996 to 2019, there were obvious spatial differences in the change of cultivated land area in 31 provincial units. From 1996 to 2008, the cultivated land area in 29 provinces showed a downward trend, especially in the central and northern regions such as Shaanxi, Sichuan and Inner Mongolia. From 2008 to 2019, the cultivated land area in the underdeveloped areas of Heilongjiang, Jilin, Liaoning, Xinjiang, Gansu and Tibet increased significantly, while the rest showed a downward trend. Factor detection found that the q values of population, regional gross domestic product grain output, the proportion of the added value of the primary industry and average slope were all more than 0.5, which had an important impact on the change of cultivated land area. The explanatory power of the interaction between factors on the change of cultivated land area is enhanced in different degrees compared with the single factor effect, which is manifested in the enhancement of bilinear or nonlinear enhancement, and the interaction of different factors promotes the change of cultivated land area. The change of cultivated land area is the result of complex interaction between factors, and is closely related to the land policy in the same period.

The rapid development of high-standard farmland construction has triggered explosion of farmland cultivated land protection technologies in recent years. Contemporary, eco-friendly fertilization technology (EFFT) are rapidly becoming main force to achieve food security and promote the national ecological strategy. Hence, based on the extended stimulus-organism-response (S-O-R) theoretical analysis framework, this empirical research 295 field interview data of farmers in the high standard farmland grain main production area in Shaanxi Province, a developing country context, to analyze the mechanism of external incentives on farmers’ eco-friendly fertilization technology adoption behavior, further tested to examine the mediating effect of intrinsic perception and moderating effect of the family endowment. We applied the methodological approach, partial least square structural equation modeling (PLS-SEM), to test the hypothetical model. The results show that external incentives can effectively improve farmers’ technology adoptive behavior; internal perception has a significant positive effect on adoptive behavior, and it plays an intermediary role between external incentives and eco-friendly fertilization technology adoption behavior; family endowment has a significant positive effect on farmers’ technology adoption behavior, but the moderating effect of family endowment in external incentive-technology adoption behavior relationship is not significant. Therefore, we should choose appropriate and flexible government regulations, and give full play to the role of premium incentives, so as to improve the motivation of farmers to adopt eco-friendly fertilization technology.

Nannochloropsis has been considered as a promising feedstock for the industrial production of violaxanthin. However, a rational breeding strategy for the enhancement of violaxanthin content in this microalga is still vacant, thereby limiting its industrial application. All-trans-lycopene locates in the first branch point of carotenogenesis. The carotenoid isomerase (CRTISO), catalyzing the lycopene formation, is thus regarded as a key enzyme for carotenogenesis. Phaeodactylum tricornutum can accumulate high-level carotenoids under optimal conditions. Therefore, it is feasible to improve violaxanthin level in Nannochloropsis by overexpression of PtCRTISO. Protein targeting analysis of seven PtCRTISO candidates (PtCRTISO1–6 and PtCRTISO-like) demonstrated that PtCRTISO4 was most likely the carotenoid isomerase of P. tricornutum. Moreover, the transcriptional pattern of PtCRTISO4 at different cultivation periods was quite similar to other known carotenogenesis genes. Thus, PtCRTISO4 was transformed into N. oceanica. Compared to the wild type (WT), all three transgenic lines (T1–T3) of N. oceanica exhibited higher levels of total carotenoid and violaxanthin. Notably, T3 exhibited the peak violaxanthin content of 4.48 mg g–1 dry cell weight (DCW), which was 1.68-folds higher than WT. Interestingly, qRT-polymerase chain reaction (PCR) results demonstrated that phytoene synthase (NoPSY) rather than ζ-carotene desaturase (NoZDS) and lycopene β-cyclase (NoLCYB) exhibited the highest upregulation, suggesting that PtCRTISO4 played an additional regulatory role in terms of carotenoid accumulation. Moreover, PtCRTISO4 overexpression increased C18:1n-9 but decreased C16:1n-7, implying that C18:1 may serve as a main feedstock for xanthophyll esterification in Nannochloropsis. Our results will provide valuable information for the violaxanthin production from Nannochloropsis.

Aggregate stability is a key factor in the evaluation of soil structure and erosion resistance, which is largely influenced by soil electric field and particle interaction. However, there are few studies on how different organic and inorganic soil conditioners change the surface electric field and interaction force of reclaimed soil to improve the aggregate stability. Therefore, a five-year field experiment was conducted to quantitatively study the effects of FeSO4 (TM), organic fertilizer (TO), fly ash (TF), maturing agent + organic fertilizer (TMO) and fly ash + organic fertilizer (TFO), compared with control (CK) treatment, on the reclaimed soil internal force and the aggregate crushing strength. The results showed that the reclaimed soil surface potential and electric field intensity increased after 5 years of application of organic and inorganic soil conditioners. Under the same electrolyte concentration and electric field conditions, the crushing strength of aggregates (p < 0.01). Generally speaking, the soil conditioners increase the net attractive force between particles, reduce the possibility of violent crushing of aggregates due to the increase of electric field intensity and improve the aggregate structural stability, among which the combined application of organic and inorganic soil conditioners has a better improvement effect. The results of this study will lay a theoretical foundation for clarifying the improvement of different soil conditioners on the reclaimed soil structural stability and erosion resistance.

Abstract Background Lipoleiomyoma is a rare, benign variant of the commonplace uterine leiomyoma. Unlike leiomyoma, these tumors are composed of smooth muscle cells admixed with mature adipose tissue. While rare, they are most frequently identified in the uterus, but even more infrequently have been described in extrauterine locations. Case presentation We describe a case report of a 45-year-old woman with a history of in vitro fertilization pregnancy presenting 6 years later with abdominal distention and weight loss found to have a 30-cm intra-abdominal lipoleiomyoma. While cross-sectional imaging can narrow the differential diagnosis, histopathological analysis with stains positive for smooth muscle actin, desmin, and estrogen receptor, but negative for HMB-45 confirms the diagnosis of lipoleiomyoma. The large encapsulated tumor was resected en bloc. The patients post-operative course was uneventful and her symptoms resolved. Conclusions Lipoleiomyoma should be considered on the differential diagnosis in a woman with a large intra-abdominal mass. While considered benign, resection should be considered if the mass is symptomatic, and the diagnosis is unclear or there is a concern for malignancy.

Individual entrepreneurial behaviors will be affected by their attitudes and environmental factors. Therefore, entrepreneurial attitude and entrepreneurial environment interpret the entrepreneurial behavior mechanism of farmers from the perspectives of internal and external factors. This manuscript is based on a survey data of farmers in five western provinces in China. Using structural equation modeling, the mechanism of the effects of farmers’ entrepreneurial attitudes and entrepreneurial environment on entrepreneurial behavior was analyzed empirically. The research results show that individual entrepreneurial attitudes and the external entrepreneurial environment cannot directly affect entrepreneurial behavior, and both will be through entrepreneurial self-efficacy. The sense of entrepreneurship indirectly affects entrepreneurial behavior, and entrepreneurial self-efficacy plays an intermediary role. The “entrepreneurial behavior structure” model proposed in this manuscript points out that cultivating entrepreneurial attitudes and creating an entrepreneurial environment cannot directly promote entrepreneurial behavior of farmers, but must stimulate farmers’ entrepreneurial behavior. The sense of self-efficacy provides a direction for the promotion of policy formulation and practical guidance for farmers’ entrepreneurship.

With the development of the economy and society, environmental pollution and resource waste problems are emerging, especially in agricultural production, and the adoption of ecological agricultural technologies is a prerequisite to alleviate ecological pressure. Based on the Technology Acceptance Model—Theory of Planned Behavior (TAM-TPB) and using research data from Hubei, Hunan, and Anhui provinces, this paper empirically analyzes the factors influencing farmers’ intention to adopt rice and shrimp crop technologies using the PLS-SEM method. The configuration path of high technology intention was further investigated by the fsQCA method. The results showed that: 1) farmers’ intention to adopt rice-shrimp crop technology was mainly positively influenced by behavioral attitude, subjective norm, perceived behavioral control, behavioral attitude; 2) Perceived usefulness and perceived ease of use had a direct effect on farmers’ intention to adopt and an indirect effect with behavioral attitude as a mediating variable, while perceived ease of use had a positive effect and perceived usefulness did not. In doing so, four configuration paths of high technology acceptance intention were obtained. Given this, this paper makes relevant suggestions, suggesting that the relevant departments focus on the comprehensive benefits of rice-shrimp crop technology; agricultural technology departments provide technical assistance to farmers, and village committees organize regular inter-farmer exchanges.

Fructose is a commonly used food additive and has many adverse effects on human health, but it is unclear whether fructose impacts pulmonary fibrosis. TGF-β1, a potent fibrotic inducer, is produced as latent complexes by various cells, including alveolar epithelial cells, macrophages, and fibroblasts, and must be activated by many factors such as reactive oxygen species (ROS). This study explored the impact of fructose on pulmonary fibrotic phenotype and epithelial-mesenchymal transition (EMT) using lung epithelial cells (A549 or BEAS-2B) and the underlying mechanisms. Fructose promoted the cell viability of lung epithelial cells, while N-Acetyl-l-cysteine (NAC) inhibited such. Co-treatment of fructose and latent TGF-β1 could induce the fibrosis phenotype and the epithelial-mesenchymal transition (EMT)-related protein expression, increasing lung epithelial cell migration and invasion. Mechanism analysis shows that fructose dose-dependently promoted the production of total and mitochondrial ROS in A549 cells, while NAC eliminated this promotion. Notably, post-administration with NAC or SB431542 (a potent TGF-β type I receptor inhibitor) inhibited fibrosis phenotype and EMT process of lung epithelial cells co-treated with fructose and latent TGF-β1. Finally, the fibrosis phenotype and EMT-related protein expression of lung epithelial cells were mediated by the ROS-activated latent TGF-β1/Smad3 signal. This study revealed that high fructose promoted the fibrotic phenotype of human lung epithelial cells by up-regulating oxidative stress, which enabled the latent form of TGF-β1 into activated TGF-β1, which provides help and reference for the diet adjustment of healthy people and patients with fibrosis.

Benthic diatoms are the main primary producers and are sensitive to environmental changes in the estuarine ecosystem. Therefore, it is critical to evaluate the impact of environmental stress on the benthic diatom community in the estuarine ecosystem. In this study, the sediment samples from the five sampling sites were collected from the Yellow River Delta in the four seasons, and the abundance of benthic diatoms were determined using the high-throughput sequencing of 18S rRNA genes. The results showed that the motile guild taxa, such as Navicula, Nitzschia, and Amphora, was dominated in the benthic diatom the community throughout the sampling period. The structure of the benthic diatom community was significantly different among seasons (ANOSIM P < 0.01), especially between summer and winter. Redundancy analysis showed that water temperature and the concentrations of silicate, nitrate, ammonium, and pH value are the main driving factors shaping the seasonal assembly of the benthic diatom community. The results will improve knowledge about the benthic diatom community in the estuarine ecosystem and provide a theoretical foundation for estuary environmental management.

Kaolinite clay mineral with a layered silicate structure is an abundant resource in China. Due to its advantages of excellent stability, high specific surface area and environmental friendliness, kaolinite is widely used in environment decontamination. By using kaolinite as a carrier, the photocatalytic technology in pure photocatalysts of poor activities, narrow spectral responses, and limited electron transport can be overcome, and the nano-Ag disinfectant’s limitation of the growth and aggregation of nanoparticles is released. Moreover, pure kaolinite used as an adsorbent shows poor surface hydroxyl activity and low cation exchange, leading to the poor adsorption selectivity and easy desorption of heavy metals. Current modification methods including heat treatment, acid modification, metal modification, inorganic salt modification, and organic modification are carried out to obtain better adsorption performance. This review systematically summarizes the application of kaolinite-based nanomaterials in environmental decontamination, such as photocatalytic pollutant degradation and disinfection, nano silver (Ag) disinfection, and heavy metal adsorption. In addition, applications on gas phase pollutant, such as carbon dioxide (CO2), capture and the removal of volatile organic compounds (VOCs) are also discussed. This study is the first comprehensive summary of the application of kaolinite in the environmental field. The review also illustrates the efficiency and mechanisms of coupling naturally/modified kaolinite with nanomaterials, and the limitation of the current use of kaolinite.

The growth and physiological process of microalgae interact with environmental nutrients. In the present study, we compared the growth and physiological characteristics of coccolithophore Chrysotila roscoffensis under the effects of phosphate at high and low concentrations, and of organic phosphorus of adenosine triphosphate (ATP) and Na2-glycerophosphate (SG). The growth, photosynthesis, calcification, alkaline phosphatase activity, and inorganic nutrient absorption rate were comparatively studied. The results showed that the culture with a low concentration of initial phosphate (6 μM) had a lower growth rate than that with a high concentration (45 μM). However, a relatively similar maximum cell density could be achieved. Equimolar inorganic phosphorus supported a higher initial growth rate than organic phosphorus. ATP was better than SG at supporting higher growth rates, higher photosynthetic activity, and higher cell density. Cellular alkaline phosphatase (AP) responded rapidly to nutrient variations with sharp changes of activities, independent of the initial P resources. Cellular calcification was at a higher level in groups with lower growth rates. Phosphate in low concentration in the medium was not absorbed during the early growth period while that in high concentration was rapidly absorbed. Instead, phosphate in low concentration was rapidly absorbed in the late stationary phase. The absorption of nitrate was affected by the initial P resources as well. The DIN/DIP ratio in the water varied significantly during the growth periods. The results indicated that C. roscoffensis had flexible physiological strategies in utilizing varied phosphorus resources, and high cell density maintenance of C. roscoffensis may play roles in nutrient conditions in the water. This study may help to extend the understanding of nutrient utilization strategy in microalgae and to apply reference in the application of Chrysotila species in the removal of nutrient pollution.

As an important part of the terrestrial ecosystem, vegetation is commonly used as an indicator to evaluate climate change and ecological restoration efforts. In China’s farming-pastoral areas, the Mu Us Desert is a typical area utilizing desertification control methods where vegetation cover has significantly changed in recent years. It is important to assess how climate change and afforestation affect vegetation activity dynamic in this region. This study aims to investigate the relationship between vegetation and climate change by using the normalized difference vegetation index (NDVI), and to find the cause of vegetation change by performing multiple linear regression analysis in the Mu Us Desert (including 11 counties) during the period from 2000 to 2019. The results showed that NDVI of the growing season (May to October) across the whole region increased by 0.0058 per year during the 20-year study period. Correlation analysis between the NDVI and climatic factors indicated that precipitation, temperature and relative humidity had a significant positive correlation, and mean wind speed and sunshine hours had a significant negative correlation across the study area (except for mean wind speed in Shenmu and Yuyang). Stepwise multiple linear regression analysis indicated that the relative contribution by climatic factors and afforestation to NDVI change was 41.9% and 58.1% across the study area, respectively. Findings from our study may help to provide scientific support for decision making concerning ecological restoration management and policy efficiency estimation in other similar desert areas.

The addition of soft rock to aeolian sandy soil can improve the level of fertility and ability of the soil to sequester carbon, which is of substantial significance to improve the ecological environment of the Mu Us sandy land and supplement newly added cultivated land. S oft rock and sand were combined using the ratio (v/v) of 0:1 (CK), 1:5 (S1), 1:2 (S2), and 1:1 (S3). The process of mineralization of organic carbon at different depths (0–10 cm, 10–20 cm, and 20–30 cm) in the combined soil was studied by 58 days of incubation indoors at a constant temperature. The content of soil nutrient s increased significantly under the S2 and S3 treatments and was higher in the 0–10 cm soil depth. The mineralization of rate of soil organic carbon (SOC) of different combination ratios can be divided into three time periods: the stress mineralization stage (1–7 d), the rapid mineralization stage (7–9 d) and the slow mineralization stage (9–58 d). At the end of incubation, the rates of mineralization of SOC and accumulated mineralization amount (Ct) were relatively large in the 0–10 cm soil depth, followed by the 10–20 cm and 20–30 cm soil layers , indicating that the stability of SOC in the surface layer was poor, which is not conducive to the storage of carbon. The content of potentially mineralizable organic carbon (C0) in the soil was consistent with the trend of change of Ct. Compared with the CK treatment, the cumulative organic carbon mineralization rate (Cr) of the S2 and S3 treatment s decreased by 7.77% and 6.05%, respectively; and the C0/SOC decreased by 22.84% and 15.55%, respectively. Moreover, the Cr and C0/SOC values in the 10–20 cm soil depth were small, which indirectly promoted the storage of organic carbon. With the process of SOC mineralization, the contents of soil microbial biomass carbon (SMBC) and dissolved organic carbon (DOC) tended to decrease compared with the initial contents, with larger amplitudes in the 20–30 cm and 10–20 cm soil depth s, respectively. SOC, total nitrogen, available potassium, SMBC and DOC were all closely related to the process of mineralization of organic carbon. Therefore, the accumulation of soil carbon could be enhanced when the proportion of soft rock and sand composite soil was between 1:2 and 1:1, and the 10–20 cm soil depth was relatively stable. These results provide a theoretical basis for the improvement of desertified land.

To estimate the long-term performance and the optimal ratio of feldspathic sandstone with sandy soil, experiments with different ratios of feldspathic sandstone to sandy soil (0:1, 1:1, 1:2 and 1:5 v/v) was conducted. The physical properties as soil texture, water-stable aggregate (WR0.25) content, and the organic carbon content of the composited soil for 6 years, and corn yield for 9 years were determined. Our results showed that after the addition of feldspathic sandstone: (1) soil texture was notably improved, changing from sand loamy soil (1:2 and 1:5) to sand loam soil (1:1) and silt sand soil (1:1) over planting time; (2) content of water-stable aggregate (WR0.25) significantly increased: WR0.25 of treatments 1:1, 1:2 and 1:5 all increased (by 29.26, 31.47 and 11.56%, respectively) compared with that of treatment 0:1; (3) the organic carbon content of the composited soils increased with time in all treatments. After six years of planting, average organic carbon content in treatments 1:1, 1:2 and 1:5 were 1.64, 1.51 and 1.77 g/kg, respectively, which were higher than that of 0:1 treatment; and (4) among the three ratios, treatment 1:2 (12 984 kg/ha) had the highest corn yield, followed by treatment 1:1 (12 040 kg/ha) and 1:5 (11 301 kg/ha). In conclusion, with a good performance, 1:2 was the best ratio of feldspathic sandstone to sand in improving the sandy soil structure of the Mu Us Desert, China.

Bacteria play a vital role in biotransformation of soil organic carbon (SOC). However, mechanisms of bacterium and organic carbon mineralization remain unclear during improvement of sandy soil using soft rock additions. In this study, four treatments with differing ratios of soft rock to sand of 0:1 (CK), 1:5 (C1), 1:2 (C2) and 1:1 (C3) were selected for mineralization incubation and high-throughput sequencing. The results showed that SOC, total nitrogen (TN), available phosphorus (AP), nitrate nitrogen (NO ${}_{3}^{-}$ 3 − -N), and mass water content (WC) of sandy soil increased significantly after addition of soft rock (P 0.05). The three dominant bacteria were Actinobacteria, Proteobacteria and Chloroflexi, among which Proteobacteria was negatively correlated with mineralization of organic carbon (P

Hydraulic properties of sandy soil from the Mu Us sandy land of Shaanxi Province were analyzed by using SEM technology. Soil porosity, the water characteristic curve, and unsaturated hydraulic conductivity of aeolian sandy soil with added soft rock were analyzed, and fractal characteristics were established. Soil hydraulic properties revealed the effect of soft rock application on soil structure and hydraulic properties. Mass ratios of soft rock to aeolian sand were 1:5, 1:2, and 1:1. Results showed that the addition of soft rock can significantly increase the bulk density of sandy soil and reduce the total porosity and macroporosity. The mass fraction of water-stable aggregates greater than 0.25mm increases significantly, increasing the fractal dimension of soil pores; reducing the soil saturated water content and saturated hydraulic conductivity. SEM technology and pore fractal theory were used to predict the soil salinity curve and unsaturated hydraulic conductivity of the improved saline soil.

In order to select excellent strains with high CO2 fixation capability on a large scale, nine Spirulina species were cultivated in columnar photobioreactors with the addition of 10% CO2. The two species selected (208 and 220) were optimized for pH value, total dissolved inorganic carbon (DIC), and phosphorus content with intermittent CO2 addition in 4 m2 indoor raceway ponds. On the basis of biomass accumulation and CO2 fixation rate in the present study, the optimum pH, DIC, and phosphate concentration were 9.5, 0.1 mol L−1, and 200 mg L−1 for both strains, respectively. Lastly, the two strains selected were semi-continuously cultivated successfully for CO2 mitigation in 605 m2 raceway ponds aerated with food-grade CO2 purified from a coal chemical flue gas on a large scale. The daily average biomass dry weight of the two stains reached up to 18.7 and 13.2 g m−2 d−1, respectively, suggesting the two Spirulina strains can be utilized for mass production.

The organic carbon mineralization process reflects the release intensity of soil CO2. Therefore, the study of organic carbon mineralization and particle composition analysis of soft rock and sand compound soil can provide technical support and a theoretical basis for soil organic reconstruction (soil structure, materials and biological nutrition). Based on previous research, four treatments were selected: CK (soft rock:sand=0:1), C1 (soft rock:sand=1:5), C2 (soft rock:sand=1:2) and C3 (soft rock:sand=1:1), respectively. Specifically, we analyzed the organic carbon mineralization process and soil particle composition by lye absorption, laser granulometer, and scanning electron microscope. The results showed that there was no significant difference in organic carbon content between C1, C2 , and C3 treatments, but they were significantly higher than in the CK treatment (P

To analyze three row orientations (south-north, east-west, southwestern 20°) and two row spacings ('65 + 65', '160 + 40'), we investigated the effect of row orientation and planting pattern on photosynthetic performance, physiological and biochemical indicators related to the aging of leaves. Results revealed that during maturity stage, in north-south and east-west, the initial fluorescence (Fo) at '65 + 65' were higher than those under'160 + 40'; the maximum quantum yield of PS2 photochemistry(ΦP0), basal quantum yield of non-photochemical processes in PS2(ΦN0)of the lower leaves and photosynthetic rate of the upper and ear leaves under'160 + 40'were higher than those under'65 + 65'. The polyphenoloxidase (POD) activities of leaves at different positions under '160 + 40' were higher than that under'65 + 65', while the malondialdehyde (MDA) content was lower. The photosynthesis rate, superoxide dismutase (SOD) and catalase (CAT) activity of leaves at different positions under southwestern 20° '160 + 40' were higher than others. Whilst MDA content '160 + 40' were lower. Therefore, in De Hui City, Jilin Province, southwestern 20° '160 + 40' delayed leaf senescence at the late stage of growth of maize, as well as the effect of increasing maize yield was most obvious.

Soil microorganisms play a pivotal role in carbon mineralization and their diversity is crucial to the function of soil ecosystems. However, the effects of long-term fertilization on microbial-mediated carbon mineralization are poorly understood. To identify the relative roles of microbes in carbon mineralization of yellow paddies, we investigated the long-term fertilization effects on soil properties and microbial communities and their relationships with carbon mineralization. The treatments included: no fertilization (CK), chemical fertilizer (NPK), organic fertilizer (M), and constant organic-inorganic fertilizer (MNPK). NPK treatment significantly increased soil water content (WC), while M and MNPK treatments significantly increased the content of soil organic carbon (SOC), total nitrogen (TN), soil microbial biomass carbon (SMBC), soil microbial biomass nitrogen (SMBN), and WC. Strong increases in CO2 emissions, potential mineralized carbon, and turnover rate constant were observed in both organic-fertilizer treatments (M and MNPK), relative to the CK treatment. These changes in soil properties can be attributed to the variation in microbial communities. NPK treatment had no significant effect. Different fertilization treatments changed soil microbial community; SOC and SMBN were the most important contributors to the variance in microbial community composition. The variations in community composition did not significant influence carbon mineralization; however, carbon mineralization was significantly influenced by the abundance of several non-dominant bacteria. The results suggest that SOC, SMBN, and non-dominant bacteria (Gemmatimonadetes and Latescibacteria), have a close relationship to carbon mineralization, and should be preferentially considered in predicting carbon mineralization under long-term fertilization.

The aim of this study is to explore suitable drip irrigation system on the water saving and high yield of pear-jujube from 2009 to 2012 years in the mountain of northern Shaanxi. The treatments consisted of combinations of 5 drip irrigation systems (DP). The irrigation quota of DP-1, DP-2 and DP-3 treatment was 100 m3 hm-2, 135 m3 hm-2 and 180 m3 hm-2, respectively, irrigated 4 times. The irrigation quota of DP-4 and DP-5 treatment was 135 m3 hm-2 and irrigated 3 and 2times, respectively; and with no irrigation as the control (C). Results indicated that bearing branch length of jujube, fruit set and yield of different drip irrigation system are significantly better than C (P

[This corrects the article DOI: 10.1371/journal.pone.0211163.].

X-ray images can be used to nondestructively monitor the initiation, extension, and combination of cracks in concrete. In this study, real-time X-ray computed tomography (CT) scanning of concrete specimens under static and dynamic loadings was done. The CT images showed the growth, propagation, and penetration of the cracks and showed the ultimate failure of the concrete samples. Analysis of the CT images and CT numbers showed that the failure followed the structure’s areas of weakness under the static load, but for dynamic loading, the cracks formed very rapidly along straight lines through the aggregate.

The main aim of this study was to compare and evaluate the performance of fractal dimension as input data in the landslide susceptibility mapping of the Baota District, Yan’an City, China. First, a total of 632 points, including 316 landslide points and 316 non-landslide points, were located in the landslide inventory map. All points were divided into two parts according to the ratio of 70%:30%, with 70% (442) of the points used as the training dataset to train the models, and the remaining, namely the validation dataset, applied for validation. Second, 13 predisposing factors, including slope aspect, slope angle, altitude, lithology, mean annual precipitation (MAP), distance to rivers, distance to faults, distance to roads, normalized differential vegetation index (NDVI), topographic wetness index (TWI), plan curvature, profile curvature, and terrain roughness index (TRI), were selected. Then, the original numerical data, box-counting dimension, and correlation dimension corresponding to each predisposing factor were calculated to generate the input data and build three classification models, namely the kernel logistic regression model (KLR), kernel logistic regression based on box-counting dimension model (KLRbox-counting), and the kernel logistic regression based on correlation dimension model (KLRcorrelation). Next, the statistical indexes and the receiver operating characteristic (ROC) curve were employed to evaluate the models’ performance. Finally, the KLRcorrelation model had the highest area under the curve (AUC) values of 0.8984 and 0.9224, obtained by the training and validation datasets, respectively, indicating that the fractal dimension can be used as the input data for landslide susceptibility mapping with a better effect.

The main aim of this study was to compare the performances of the hybrid approaches of traditional bivariate weights of evidence (WoE) with multivariate logistic regression (WoE-LR) and machine learning-based random forest (WoE-RF) for landslide susceptibility mapping. The performance of the three landslide models was validated with receiver operating characteristic (ROC) curves and area under the curve (AUC). The results showed that the areas under the curve obtained using the WoE, WoE-LR, and WoE-RF methods were 0.720, 0.773, and 0.802 for the training dataset, and were 0.695, 0.763, and 0.782 for the validation dataset, respectively. The results demonstrate the superiority of hybrid models and that the resultant maps would be useful for land use planning in landslide-prone areas.