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Aluminum–wood–plastic composite (A-WPC) beams are a novel type of structural components formed by the co-extrusion of a wood–plastic composite (WPC) on the surface of a hot-rolled aluminum plate. In this study, composite beams of three different spans were designed to examine the flexural performance of A-WPC beams. For each group of specimens, the four-point flexural test was conducted to determine and analyze the failure mode, yield load, flexural bearing capacity, strength utilization, deformability, and strain distribution. The results show that when the span–height ratio is low, folding failure occurs on the compression side of the reinforced A-WPC composite beam, whereas when the span–height ratio is large, deformation and cracks occur on the tension side of the reinforced A-WPC beam first. Compared to the specimen with a span–height ratio of 18, the average ultimate load of the specimen with a span–height ratio of 12 was higher(66.75%), while the average deflection at failure was lower(38.03%). Compared to the specimen with a span–height ratio of 12, the average ultimate load of the specimen with a span–height ratio of 6 was higher(65.97%), while the average deflection at failure was lower(43.86%). The strength utilization of the reinforced A-WPC beam is 8.71%–9.26% higher than that of various engineered wood beams, and 3.46%–8.61% higher than that of various glulam beams. Based on these results, this paper proposed a method for calculating the flexural bearing capacity of the A-WPC beam. The calculation and test results indicate that the reinforced A-WPC beam exhibits excellent flexural performance and can be used as a model for composite beam design. • The reinforcement design of composite beam with aluminum–woodplastic​ composite. • The failure modes and experimental characterization of flexural test of reinforced aluminum–wood–plastic composite beam. • The flexural bearing capacity calculation of reinforced aluminumwood–plastic-composite beam. [ABSTRACT FROM AUTHOR]

• An integrated patch-based habitat suitability assessment method for nationwide locust area extraction is proposed. • Dynamic changes of locust area and its evolution in China from 1995 to 2017 are analyzed. • The influences of land use/cover change on locust area evolution are quantified. • Suggestions for locust area management and monitoring are provided. The Oriental migratory locust (Locusta migratoria manilensis) is a threat to agriculture in China. The locust area is defined as an area possessing a suitable breeding habitat for this locust and has a locust outbreak at least once per decade. Ecological control of the locust area is an effective approach to manage locust with minimal environmental degradation. The formation and dynamic changes of locust areas are greatly affected by land use/cover changes (LUCC). Clarifying the LUCC in the locust area is significant for implementing rational ecological control strategies and detecting timely potential locust areas. This paper proposed a patch-based habitat suitability assessment (PHSA) method for nationwide locust area extraction. Then, a multi-temporal binary coding method was used to detect the locust area dynamic changes from 1995 to 2017. Subsequently, the relationship between LUCC and the extinction and formation of locust areas in different ecotypes was quantitatively investigated. Results show that the area of the locust area has greatly reduced over the past 20 years, and the distribution range has a large degree of temporal and spatial variation. The extinction of the locust area is closely related to the LUCC from cropland and wetland to woodland and artificial surface. It is also related to changes from grassland to cropland and woodland. The newly formed locust area shows opposite LUCC trends. These results provide practical strategies and guidance for ecological control and early monitoring of locust areas. They are instrumental in reducing pesticide use and achieving more sustainable agriculture. [ABSTRACT FROM AUTHOR]

Bamboo fiber (BF) possesses advantages such as environmental friendliness, renewability, economic viability, and favorable mechanical properties, making it a promising material for improving the brittleness and tensile strength of concrete. Previous investigations have demonstrated a limited exploration of BF-reinforced lightweight aggregate concrete (LWAC). Current study concentrates on investigating the mechanical properties and stress-strain relationship of BF-reinforced LWAC. To achieve this, 7 groups of BF-reinforced LWAC specimens were subjected to compressive tests, splitting tensile tests, and prism compressive tests. The influence of BF content and length on the compressive performance, failure modes and stress-strain curves was studied. BFs effectively suppressed the development of internal cracks in LWAC, playing a role in crack resistance and toughness enhancement. Furthermore, BFs significantly improved the splitting tensile strength of concrete, while the compressive strength slightly decreased with the increase of BF content. After adding BFs, the splitting tensile strength of concrete increased by 8.2∼23.7%, and the compressive strength decreased by 3.6∼11.1%. Moreover, the BF length had almost no effect on the compressive strength of concrete, while when the BF length was 10–30 mm, the tensile strength increased by 5.3∼17.6%. Based on existing researches, strength conversion equations and stress-strain constitutive models of BF-reinforced LWAC were proposed, and the models provide a theoretical basis for the calculation and analysis of BF-reinforced LWAC components and structures. • Bamboo fiber (BF)-reinforced lightweight aggregate concrete (LWAC) was examined. • BFs significantly improved the splitting tensile strength and ductility of LWAC. • The failure modes of specimens were analyzed based on SEM images and DIC technology. • The stress-strain models of BF-reinforced LWAC were established. [ABSTRACT FROM AUTHOR]

[Display omitted] • The novel CRSEI minimizes error in continuous monitoring of environmental quality. • Multitemporal bias of standard RSEI is reduced with a change detection algorithm. • CRSEI reveals actual environmental-quality changes in East/Southeast Asian coasts. • North China coasts have low environmental quality but see the most improvement. • Southeast Asian coasts see major environmental deterioration caused by human activity. With urbanization and anthropogenic pressures, the eco-environmental quality of East and Southeast Asian coastal regions has undergone drastic changes in the 21st century. To assess these environmental variations and realize regional sustainable development goals, a quantitative monitoring of the eco-environment is necessary, but challenging. The remote sensing ecological index (RSEI) was recently proposed and applied to quantitatively monitor the eco-environmental quality, but bias during multitemporal observations is a major limitation. Thus, a novel method, Continuous Remote Sensing Ecological Index (CRSEI), was developed in this study to enable constant and objective monitoring of large-scale and long-term environmental changes in the coastal regions of East and Southeast Asia. To reduce the multitemporal bias of pixels caused by imaging conditions and sensor status, a change detection algorithm requiring limited auxiliary data was developed. High-resolution images show that the CRSEI enables adequate multitemporal monitoring of eco-environmental changes with fewer false fluctuations on the local scale. The proposed CRSEI should deepen the current understanding of environmental changes and provide a solid scientific reference for environmental protection on multiple scales. The results of this research indicate that the eco-environmental quality of the east and southeast Asian coast remained generally stable during the studied period (2001–2019), with the mean CRSEI changed slightly from 5918 to 5856. However, on a regional level, each area revealed different conditions. First, the Korean Peninsula had relatively stable and well-maintained eco-environmental quality with a CRSEI of around 5500 during 2001–2019. Second, The North China coast had lower eco-environmental quality compared to other regions, but it showed the most improvement, with the CRSEI increasing from 2719 to 2807. Third, the eco-environmental quality of South China and Myanmar's coastal region remained relatively stable, with a CRSEI of around 5730 and 6720, respectively. Fourth, the continental coast of some Southeast Asian countries, particularly Vietnam and Cambodia, experienced a significant decline in eco-environmental quality, as indicated by a dramatic decrease in the CRSEI from 6751 to 6527. Notably, the areas with declining eco-environmental quality were concentrated in the western border regions of Cambodia, where unrestricted cultivation has led to the destruction of tropical rainforests. [ABSTRACT FROM AUTHOR]

In East Inner-Mongolia, the Arxan-Chaihe Volcano Area (ACVA) constitutes an important component part of the Cenozoic volcanic eruption area in Northeast China, with great scientific and aesthetic value. The area has received much attention since the 1980s. The Arxan National Geopark was established in 2004 and the Zalantun Autonomous Geopark in 2010, and volcanic geoconservation and geotourism developed to a certain degree, along with some common problems in geopark development. This paper analyzes the characteristics, geoconservation, and geotourism of volcanic geoheritage in the area. The main problems identified are the inefficient conservation management, uncoordinated development, and the limited interpretation system. We provide some suggestions on the problems in order to promote the local development, such as strengthening legislation, training tour guides as volcanologists with a background in geology who can interpret volcano geoheritage correctly, building a web site, and combining the two geoparks to apply for designation as a global geopark [ABSTRACT FROM AUTHOR]