This study investigated the interactions between two arbuscular mycorrhizal fungi (AMF) (Glomus aggregatum and Glomus mosseae) and a P-solubilizing fungus (Mortierella sp.), with respect to their effects on growth of Kostelelzkya virginica and urease, invertase, neutral phosphatase, alkaline phosphatase, and catalase activities of rhizosphere and bulk soils at different salinity levels (i.e

Plant communities across multiple climate zones are at risk of invasive species. Understanding the effects of invasive alien species on both the taxonomic and functional diversities of plant communities in different climate zones enables insight into the mechanisms underlying successful invasions. This study investigated the effects of Erigeron canadensis at different degrees of invasion on both the plant taxonomic and functional diversities in the Chinese zones of Jinan (warm temperate climate) and Zhenjiang (north subtropical climate). A high degree of E. canadensis invasion resulted in a stronger decrease of plant diversity compared to a light degree of E. canadensis invasion. This may be because E. canadensis invasion can lead to a decrease in the number of native species via competition and subsequent local extinction. A high degree of E. canadensis invasion increased the Rao's quadratic entropy of plant height and ground cover. This may be because both the plant height and ground cover of E. canadensis and natives increased with increasing degree of E. canadensis invasion. The number of plant species in plant communities was lower in Jinan than in Zhenjiang. This is presumably because E. canadensis grows better in Jinan than in Zhenjiang and therefore, rare species are more likely to go extinct there. A small number of functional diversity indices of Jinan plant communities were higher than those of Zhenjiang. This may be due to the higher value of functional traits of E. canadensis in Jinan.

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The strength of filled bolt holes of composites is an important parameter in developing the bearing bypass envelope curves for bolted joint structures in engineering design. This paper presents the procedures of tensile failure strengths and damage for a laminate with a filled bolt hole. Tests of two different cases, open‐hole tension (OHT) and filled‐hole tension (FHT), were performed and repeated seven times, respectively. A new type of virtual testing based on the LaRC05 criteria coupling with XFEM crack technique was developed to predict and analyze the crack initiation and early propagation around the bolt hole in the laminates. Two analytical methods were also adopted to predict the residual strength for a laminate after drilling. The results show that the thinner sample would present a higher strength with the same material system. It is also shown that the virtual test can well capture the failure modes, revealing that the 0° fiber has a natural function of crack arrest, the 90° layers that are the fracture pioneers with matrix tensile failure trigger the fiber breakage of 0° layers, and the failure of 45° layers occurs at the last. Additionally, an interesting phenomenon is observed that the initial failure around the filled hole edge does not affect the structural stiffness. Finally, a good agreement is achieved among the experimental, analytical and numerical results. It suggests that the results could provide a valuable guidance for the design of multi‐bolted joint structure.

A comprehensive understanding of the relationship between arbuscular mycorrhizal (AM) fungi and coastal saline soil organic carbon (SOC) is crucial for analysis of the function of coastal wetlands in soil carbon sequestration. In a field experiment, the temporal and spatial dynamics of AM fungi, glomalin-related soil protein (GRSP) – which is described as a N-linked glycoprotein and the putative gene product of AM fungi, SOC, and soil aggregates were investigated in halophyte Kosteletzkya virginica rhizosphere soil of coastal saline areas of North Jiangsu, China. Soil samples were collected from a depth of up to 30 cm in two plantation regions from August 2012 to May 2013. Results showed K. virginica formed a strong symbiotic relationship to AM fungi. AM colonization and spore density were the highest in the 10–20 cm soil layer of Jinhai farm in August 2012, because of the presence of numerous fibrous roots in this soil layer. The total GRSP and SOC were the highest in the 0–10 cm soil layer in May 2013 and November 2012, respectively. Correlation coefficient analysis revealed that AM colonization and spore density were positively correlated with total GRSP. Meanwhile, total GRSP was significantly positively correlated with large macroaggregates (>3 mm), SOC, total P, Olsen P, and soil microbial biomass carbon (SMBC), but negatively correlated with microaggregates (<0.25 mm), soil EC, total N, and pH. SOC was positively correlated with spore density, large macroaggregates, small macroaggregates (2–0.25 mm), alkaline N, and SMBC and negatively correlated with microaggregates, EC, pH, and total K. Although it may be a statistical artifact, we found an interesting phenomenon that there was no significant correlation between soil aggregates and AM colonization or spore density. Hence, total GRSP is a vital source of saline soil C pool and an important biological indicator for evaluating coastal saline SOC pool and soil fertility, while AM colonization or spore density may not be.