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A typical county for traditional village conservation in China is Songyang County. It is renowned for its ancient rammed earth dwellings, which exhibit a unique microclimate and possess significant historical value. However, high precipitation and acid rain under the subtropical monsoon climate have caused severe surface erosion, including cracking and spalling. This study focuses on traditional rammed earth dwellings in Chenjiapeng Village, Songyang County, combining field surveys, experimental analysis, and microscopic characterization to systematically investigate erosion mechanisms and protection strategies. Techniques, such as drone aerial photography, X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), and microbial diversity detection, were employed to elucidate the anti-erosion mechanisms of gray-green biological crusts on rammed earth surfaces. The results indicate that algal crusts enhance surface compressive strength and shear resistance through macroscopic coverage (reducing raindrop kinetic energy and moisture retention) and microscopic extracellular polysaccharide-cemented soil particles forming a three-dimensional network. However, acidic environments induce metabolic acid release from algae, dissolving cementing materials and creating a surface protection-internal damage paradox. To address this, a transparent film-biofiber-acid inhibition layer composite biofilm design is proposed, integrating a biodegradable polylactic acid (PLA) mesh, algal attachment substrates, and calcium carbonate microparticles to dynamically neutralize acidic substances, achieving synergistic ecological protection and cultural heritage authenticity. This study provides innovative solutions for the anti-erosion protection of traditional rammed earth structures, emphasizing environmental compatibility and sustainability.

期刊论文 2025-05-20 DOI: 10.3390/coatings15050608 ISSN: 2079-6412

With global climate change and the deterioration of the ecological environment, the safety of hydraulic engineering faces severe challenges, among which soil-dwelling termite damage has become an issue that cannot be ignored. Reservoirs and embankments in China, primarily composed of earth and rocks, are often affected by soil-dwelling termites, such as Odontotermes formosanus and Macrotermes barneyi. Identifying soil-dwelling termite damage is crucial for implementing monitoring, early warning, and control strategies. This study developed an improved YOLOv8 model, named MCD-YOLOv8, for identifying traces of soil-dwelling termite activity, based on the Monte Carlo random sampling algorithm and a lightweight module. The Monte Carlo attention (MCA) module was introduced in the backbone part to generate attention maps through random sampling pooling operations, addressing cross-scale issues and improving the recognition accuracy of small targets. A lightweight module, known as dimension-aware selective integration (DASI), was added in the neck part to reduce computation time and memory consumption, enhancing detection accuracy and speed. The model was verified using a dataset of 2096 images from the termite damage survey in hydraulic engineering within Hubei Province in 2024, along with images captured by drone. The results showed that the improved YOLOv8 model outperformed four traditional or enhanced models in terms of precision and mean average precision for detecting soil-dwelling termite damage, while also exhibiting fewer parameters, reduced redundancy in detection boxes, and improved accuracy in detecting small targets. Specifically, the MCD-YOLOv8 model achieved increases in precision and mean average precision of 6.4% and 2.4%, respectively, compared to the YOLOv8 model, while simultaneously reducing the number of parameters by 105,320. The developed model is suitable for the intelligent identification of termite damage in complex environments, thereby enhancing the intelligent monitoring of termite activity and providing strong technical support for the development of termite control technologies.

期刊论文 2025-03-31 DOI: 10.3390/s25072199

Zhuanyao dwellings faced significant seismic risks in rural regions of China. Therefore, a shaking-table test was performed to explore the seismic performance of Zhuanyaos and validate the finite-element simulation results. The results showed that the damage to the pier and roof levels of Zhuanyaos was more severe after earthquakes, resulting in a noteworthy increase in the displacement responses of these two levels compared to that of the vault level. The damage to the front structure (Yaolian) and mid-pier of the Zhuanyao were more severe than the damage to the back wall and side pier, respectively, which caused a significant reduction in acceleration responses of Yaolian and mid-pier. Following the crack development, dynamic response, and field investigation, three typical collapse modes of Zhuanyaos were presented. Subsequently, the parametric analysis was conducted using a verified finite-element simulation method. The results show that using the catenary arch can reduce earthquake damage in Zhuanyaos. Increasing the width of the middle pier can improve the seismic performance of Zhuanyaos to a certain extent; however, it may exacerbate local damage to the structure. Besides, the high seismic vulnerability of Zhuanyaos stemming from an increasing thickness of overlying soil cannot be ignored.

期刊论文 2024-08-01 DOI: 10.1007/s10518-024-01899-9 ISSN: 1570-761X

Fall armyworm, Spodoptera frugiperda is an invasive polyphagous pest and has annually invaded Korea since it was first reported in 2019. This pest has already acquired resistance to synthetic chemical pesticides. To minimize the damage caused by S. frugiperda, alternative control methods with different mode of action should be developed. In this study, we assessed the virulence of native entomopathogenic fungi against S. frugiperda and investigated application methods to effectively control the target insect. We obtained 93 fungal isolates and assayed their pathogenicity against second instar larvae. Of the 93 isolates, 34 isolates caused high mortality. Based on their virulence, conidial productivity, and thermotolerance, ten isolates were selected for quantitative bioassays. In the bioassays using leaf dipping, all isolate treatments showed high virulence against second instar larvae, but only two isolates, Beauveria bassiana JEF-492 and Sf83 caused 93.3% and 86.7% mortality against fourth instar larvae, respectively. Given the soil-dwelling pupal stage, drenching the soil with Metarhizium anisopliae JEF-157 and B. bassiana JEF-492 from the selected isolates reduced the survival rate of pupae by up to 80% under laboratory conditions. The M. anisopliae JEF-157 and B. bassiana JEF-492 cultured on barley and rice showed high conidial productivity and thermotolerance. Our results show that soil application of M. anisopliae JEF-157 and B. bassiana JEF-492 targeting pupal stage could be effectively combined with the spray on the leaf-dwelling larval stage when the isolates encounter unfavorable abiotic stress on the leaves.

期刊论文 2024-03-01 DOI: 10.1016/j.aspen.2023.102193 ISSN: 1226-8615

Underprivileged people in many parts of Asia, Africa, Europe, and Latin America use earthen dwellings because of environmental and economic advantages. However, such non-engineered structures often encounter unacceptable risks from various natural calamities such as earthquakes, floods, etc. The 3rd January 2017 moderate earthquake in Tripura (NE India) is prime evidence of severe damage to earthen houses in rural Tripura. The present research focuses on enhancing the seismic strength of traditional earthen houses through mechanical stabilization with locally available low-cost sustainable natural fibers (i.e., jute and straw) and stabilizing materials (i.e., clay and lime), respectively. Primarily, the shear and flexural strength of both stabilized and unstabilized model rammed earthen wallettes are investigated experimentally. Thereafter, a 3D finite element (FE) numerical model is developed to verify the sanctity of the experimental findings. The study reveals that fiber-reinforced earthen wallettes, especially jute fiber-reinforced wallettes, exhibited significant improvement in shear and flexural strength including ductility behaviour whereas, clay and lime-stabilized wallettes offered improvement in strength exhibiting brittle failure. Finally, the seismic response of a prototype fiber-reinforced rammed earth wall is evaluated through 3D FE-based numerical modelling considering the input motion of the 2017 Tripura earthquake which also indicated significant improvement compared to the unimproved one. However, from the viewpoint of sustainability, it is concluded that carbon emissions of approx. 38% may be reduced in the case of natural fibers such as jute and straw compared to synthetic stabilizing agents (i.e., lime). Hence, the study promotes the use of low-cost sustainable fibers with a lower carbon footprint and minimum energy consumption in earthen houses.

期刊论文 2024-01-22 DOI: 10.1007/s12046-023-02375-x ISSN: 0256-2499

Soils and occupation layers of dwellings and livestock pens located in the western part of the Crimean peninsula were investigated employing methods of archaeoparasitology and soil microbiology. The studies were carried out at several sites, namely, Tyumen-3, Tyumen-7 and Bagai-1. Eggs of two types of helmints, presumably, Dicrocoeliidae and Trichuridae families, were identified in the selected samples. Trematodes of the Dicrocoeliidae family cause dicroceliosis, which is a parasitic disease, predominantly, of sheep, cattle, horses, pigs, etc. This trematode can be dangerous for humans. Trichuridae are roundworms which, depending on species, infest the intestine of humans, sheep, dogs, pigs, etc. Depending on severity of disease, the invasion of this helmint in humans and animals can be characterized by both asymptomatic disease course and clinical manifestations caused by damage to the colon mucosa, intoxication of the organism by excreta, etc. Close correlation between the incidence rate of the Trichuridae family eggs and urease enzyme activity and CFU counts for thermophilic bacteria was found. A high incidence rate of whipworms and increased values of the aforementioned microbiological indicators are linked with conservation conditions of the occupation layer. High incidence of eggs of the trematodes of the Dicrocoeliidae families was found to closely correlate with larger numbers of CFU for saprotrophic bacteria and keratinolytic fungi, this genus of helmints was identified in equal qualities both in livestock pens and dwellings. Hence, this study was the first to prove that such livestock diseases as dicroceliosis and trichocephalosis probably were common in the Late Bronze Age.

期刊论文 2024-01-01 DOI: 10.25681/IARAS.0130-2620.277.399-417 ISSN: 0130-2620
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