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We evaluated the diversity of soil macrofauna communities inhabiting urban green spaces in Yancheng City, an urbanizing city located east of China. In the end of April 2011, the taxonomic richness, abundance and composition of soil macrofauna communities were assessed and compared among five types of green space (poplar forest, rapeseed farm, grassland in park, lawn and nursery garden) and three depth layers in the soil, with taxonomic resolution attained at the order level. Taxonomic richness (orders) and abundance were significantly different among green spaces. Diversity indices (Margalef's taxonomic richness R and Shannon-Weaver diversity index H') were higher in poplar forest, grassland in park and nursery garden than in rapeseed farm and lawn. Taxonomic richness (Chao 2) showed a similar trend. There were significant effects of green space type and soil layer, which showed a significant interaction affecting macrofauna composition. We recommend that urban green spaces can be used for maintaining biodiversity, not only for landscape purposes.Evaluamos la diversidad de las comunidades de macrofauna del suelo que habitan los espacios verdes urbanos en la ciudad de Yancheng, una ciudad en proceso de urbanización situada al este de China. A fines de abril 2011, la riqueza taxonómica, abundancia y composición de comunidades de macrofauna del suelo fueron evaluadas y comparadas entre cinco tipos de espacio verde (bosque de álamos, granja de colza, pastizal de parque, césped y jardín vivero) y tres capas de profundidad del suelo, con resolución taxonómica a nivel de orden. La riqueza taxonómica (de órdenes) y la abundancia fueron significativamente diferentes entre los espacios verdes. Los indices de diversidad (riqueza taxonómica R de Margalef y diversidad H' de Shannon-Weaver) fueron mayores en el bosque de álamos, pastizal de parque y jardin vivero que en la granja de la colza y el césped. La riqueza taxonómica (Chao 2) mostró una tendencia similar. Hubo efectos significativos del tipo de espacio verde y capa del suelo, los cuales mostraron una interacción significativa afectando la composición de la macrofauna. Recomendamos que los espacios verdes urbanos se puedan utilizar para mantener la biodiversidad, y no solo con propósitos de paisaje.

Mesoporous CoS/MoS2 with abundant heterogeneous interfaces was faciley synthesized from a bimetallic hybrid zeolitic imidazolate framework, which showed excellent catalytic activity and reaction kinetics in both the HER and OER in 1 M KOH. Meanwhile, as a cathode and anode in water splitting electrocatalysis, it delivers a low cell voltage of 1.61 V at 10 mA cm−2 and excellent durability. [ABSTRACT FROM AUTHOR]

Species of the order Crocodylia are mostly large, predatory and semi-aquatic reptiles. Crocodylia, the closest living relatives of birds, first appeared in the Late Cretaceous period. In the present study, the complete mitochondrial (mt) genomes of 19 Crocodylia species, including two species (Melanosuchus niger and Caiman yacare) that have not been previously sequenced for mitogenomes, were processed through Illumina sequencing to offer genetic resources and compare with the mitogenomes of Crocodylia species reported previously. In addition, a high-resolution phylogenetic tree of nearly all current recognized species of Crocodylia is constructed based on mitogenomic data. Phylogenetic analyses support monophyly of three families: Alligatoridae (four genera: Alligator , Caiman , Melanosuchus and Paleosuchus), Crocodylidae (three genera: Crocodylus , Mecistops and Osteolaemus) and Gavialidae (two genera: Gavialis and Tomistoma). The tree topology is generally similar to previous studies. Molecular dating suggests that the first split within Crocodylia date back to the Upper Cretaceous (approx. 86.75 Mya). The estimated time to the most recent common ancestor (TMRCA) of Alligatoridae is 53.33 Mya and that of Crocodylidae and Gavialidae is 50.13 Mya, which might be closely linked to climate changes during the Late Palaeocene and Early Eocene. Additionally, this study proves that the diversification rate within Crocodylia began to increase from the Late Eocene (about 36 Mya) and two diversification peak periods of Crocodylia (0–10 Mya and 10–20 Mya) are disclosed, which is roughly consistent with the estimated crocodylian species richness through time. Combining all these clues, we can suggest that climate fluctuation may have played a decisive role in the speciation of Crocodylia. [ABSTRACT FROM AUTHOR]

A semianalytical solution of stress and displacement in the strain-softening and plastic flow zones of a salt cavern is presented. The solution is derived by adopting the large deformation theory, considering the nonlinear Hoek–Brown (H-B) strength criterion. The Romberg method is used to carry out numerical calculation, and then, the large deformation law of displacement is analyzed. The results are compared with those obtained by former numerical methods, and the solutions are validated. The results indicate that the displacement of the plastic zone decreases with the increase in distance away from the salt cavern. Similarly, it decreases with an increase in the geological strength index or running pressure, with the running pressure having a more significant effect on the displacement. It increases with the dilation angle, and the impact degree gradually increases. Compared with the softening parameter, h , of the plastic zone, the flow parameter, f , has little impact on the displacement. The displacement of the plastic zone obviously increased when considering the strain-softening of salt rock. When considering the shear dilation and softening behaviors of salt rock, the analytical solution obtained by employing the experiential regression Hoek–Brown (H-B) criterion, which considers many factors such as the structural characteristics of the salt formation and the rock mass quality, is safer and closer to the actual situation. This study can provide reference for many applications, including but not confined to analyzing the deformation of the surrounding rock of an underground salt cavern storage facility during construction. [ABSTRACT FROM AUTHOR]