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Soil faunal communities play key roles in maintaining soil nutrient cycling. Affected by different land-use types, soil environment and soil faunal communities change significantly. However, few studies have focused on the aforementioned observations in coastal zones, which provide suitable habitats for many species of concern. Here, we investigated the changes in soil mesofaunal communities under different land-use types, including cotton fields, jujube trees, ash trees, a saline meadow, and wetlands. The variations in land-use types affected the community composition and diversity of soil mesofauna in the coastal zones. The taxa of soil mesofauna had different responses to land-use types in the coastal zones. Isotomidae was regarded as an indicator taxon of the coastal cropland regions. Entomobryidae was considered to be an indicator taxon of coastal artificial trees. Meanwhile, Onychiuridae and three taxa (Brachycera, Armadillidiidae, and Gammaridae) were indicator taxa of the coastal terrestrial ecosystem and the coastal wetland ecosystem, respectively. Thus, we suggested that specific soil mesofaunal taxa were considered to be appropriate bioindicators for land-use types in the coastal zones. The results of this study were helpful to develop guidelines for coastal biodiversity and ecosystem conservation in the future. [ABSTRACT FROM AUTHOR]

Constructed wetlands can play an active role in improving the water quality of urban rivers. In this study, a sequential series system of the floating-bed constructed wetland (FBCW), horizontal subsurface flow constructed wetland (HSFCW), and surface flow constructed wetland (SFCW) were constructed for the urban river treatment in the cold regions of North China, which gave full play to the combined advantages. In the Yitong River, the designed capacity and the hydraulic loading of the system was 100 m3/d and 0.10 m3/m2d, respectively. The hydraulic retention time was approximately 72 h. The monitoring results, from April to October in 2016, showed the multiple wetland ecosystem could effectively remove chemical oxygen demand (COD), ammonia nitrogen (NH4+-N), total nitrogen (TN), total phosphate (TP), and suspended solids (SS) at average removal rates of 74.79%, 80.90%, 71.12%, 78.44%, and 91.90%, respectively. The removal rate of SS in floating-bed wetland was the largest among all the indicators (80.24%), which could prevent the block of sub-surface flow wetland effectively. The sub-surface flow wetland could remove the NH4-N, TN, and TP effectively, and the contribution rates were 79.20%, 64.64%, and 81.71%, respectively. The surface flow wetland could further purify the TN and the removal rate of TN could reach 23%. The total investment of this ecological engineering was $12,000. The construction cost and the operation cost were $120 and $0.02 per ton of polluted water, which was about 1/3 to 1/5 and 1/6 to 1/3 of the conventional sewage treatment, respectively. The results of this study provide a technical demonstration of the restoration of polluted water in urban rivers in northern China. [ABSTRACT FROM AUTHOR]

Understanding the characteristics of the balanced nutrient requirements for peanut to achieve target yields is paramount when formulating fertilizer management strategies to increase yields and avoid fertilizer loss. Nutritional requirement estimation models can provide effective alternatives for the estimation of the optimum crop balanced nutrient requirements under varied agricultural conditions which are less time consuming and expensive. In the present study, the quantitative estimation of the optimum crop balanced nutrient requirements of peanut in China were obtained using quantitative evaluation of fertility of tropical soils (QUEFTS) model. The database covered the main agro-ecological region for peanut crops in China between 1993 and 2018. The predicted results of the QUEFTS model indicated that nutrient uptake requirements increased linearly with increasing pod yields until the yields had reached approximately 60% to 70% of the potential pod yields. It was found that with the increasing pod yields during the nutrient linear absorption stage, the plants had required 38.4 kg N, 4.3 kg P, and 14.0 kg K in total to produce 1000 kg of pods, and the corresponding internal efficiencies were 26.0 kg N/kg, 235.0 kg P/kg, and 71.6 kg K/kg, respectively. In addition, the balance rates of the removal nutrient in the pods were determined to be 29.4 kg N, 2.9 kg P, and 4.9 kg K per 1000 kg of pod yield, or approximately 76.5%, 67.4%, and 34.7% of N, P, and K in the total plants, respectively. This study's field validation experiments verified the applicability and accuracy of the QUEFTS model. Therefore, it was considered to be an effective alternative for the estimation of the optimal balance N, P, and K uptake requirements for peanut crops. These findings will potentially be helpful when making future decisions regarding fertilizer recommendations for peanut crops in China. [ABSTRACT FROM AUTHOR]

Deyeuxia purpurea, a low-altitude species, has been expanding upwards into alpine tundra, and this upward expansion is causing serious ecological consequences. However, few studies have been performed regarding its effects on soil faunal communities. We examine how the upward expansion of D. purpurea affects the abundance, richness, and diversity of soil mesofauna, and evaluate how different taxa of soil mesofauna respond to the upward expansion of D. purpurea in the alpine tundra of Changbai Mountains, northeast China. A total of 128 soil mesofaunal samples were collected from four treatments, namely high upward expansion (HU), medium upward expansion (MU), low upward expansion (LU), and native plant habitats (NP). The results revealed that the abundance of soil mesofauna was increased with the rise of D. purpurea upward expansion, and the taxonomic composition varied with the different levels of D. purpurea upward expansion in the alpine tundra of the Changbai Mountains. No unique taxa were collected in the native plant habitats, and the upward expansion of D. purpurea promoted the colonization of predatory invertebrates. Isotomidae and Gamasida responded positively to the herbaceous plant upward expansion, and thus they were considered to be a positive indicator of upward expansion. Hypogastruridae and Enchytraeidae responded relatively negatively, while Oribatida, Actinedida, and Pseudachorutidae had ambivalent responses to the upward expansion. Overall, the abundance of soil mesofauna can indicate the levels of the upward expansion of D. purpurea. Soil mesofaunal guild characteristics were altered by the upward expansion. The different taxa of soil mesofauna responded to herbaceous plants' upward expansion to various degrees. Therefore, this study provide evidence supporting the fact that the abundance of soil mesofauna can indicate the levels of upward expansion of D. purpurea, but the responses of soil mesofauna to the upward expansion of D. purpurea differ among their taxa. [ABSTRACT FROM AUTHOR]

The harsh environmental conditions in alpine tundra exert a significant influence on soil macro-arthropod communities, yet few studies have been performed regarding the effects of vegetation heterogeneity on these communities. In order to better understand this question, a total of 96 soil macro-arthropod samples were collected from four habitats in the Changbai Mountains in China, namely, the Vaccinium uliginosum habitat, Sanguisorba sitchensis habitat, Rhododendron aureum habitat, and Deyeuxia angustifolia habitat. The results revealed that the taxonomic composition of the soil macro-arthropods varied among the habitats, and that dissimilarities existed in these communities. The abundance, richness and diversity in the D. angustifolia habitat were all at their maximum during the sampling period. The vegetation heterogeneity affected the different taxa of the soil macro-arthropods at various levels. In addition, the vegetation heterogeneity had direct effects not only on soil macro-arthropod communities, but also indirectly impacted the abundance, richness and diversity by altering the soil fertility and soil texture. Overall, our results provide experimental evidence that vegetation heterogeneity can promote the abundance, richness and diversity of soil macro-arthropods, yet the responses of soil macro-arthropods to vegetation heterogeneity differed among their taxa. [ABSTRACT FROM AUTHOR]

• Soil meso -faunal richness and diversity responded sensitively to the impacts of oil exploitation on wetlands. • Oil exploitation mainly affected the soil meso -faunal community by changing the soil environment and vegetation characteristics. • Taxa composition of the soil meso -fauna in wetlands effectively indicated the impacts of oil exploitation on wetlands and the ecological health of wetlands. Soil meso -fauna can indicate ecological health and provide biotic metrics for evaluating ecosystem damage and environmental changes. However, the roles of the soil meso -fauna in wetlands affected by oil exploitation have rarely been studied. This study investigated the community of the soil meso -fauna and the soil environmental quality in the oil exploitation area (oil well area, transitional area, and natural area) of the Momoge wetland, China. The results revealed that the oil pollutants (polycyclic aromatic hydrocarbons, PAHs) in the oil exploitation area mainly contained 2–3 rings soil PAHs. Oil exploitation mainly affected the soil meso -faunal community by changing the soil environment and vegetation characteristics. The abundance and richness of the soil meso -fauna were negatively affected by oil exploitation, and the richness responded more sensitively than the abundance. The diversity and taxa composition of the soil meso -fauna can be used to indicate the impacts of oil exploitation on wetland ecosystems and assess the ecological health of wetlands. The terrestrial taxa of the soil meso -fauna in wetlands (Coccoidea, Carabidae larvae, Hydrophilidae larvae, and Aphididae) could tolerate the oil pollutants and intense exploitation disturbance, indicating a highly disturbed wetland ecosystem. The aquatic (Chironomidae) and terrestrial taxon (Tenebrionoidea) indicated an intermediately disturbed wetland ecosystem. The aquatic (Enchytraeidae and Tabanidae) and non-aquatic taxa (Lposcelididae, Oecobiidae, and Tenthredinidae) indicated an undisturbed natural wetland ecosystem. The results of this study provide promising opportunities for oil production management and conservation efforts for wetland resources and biodiversity. [ABSTRACT FROM AUTHOR]

Summary: In 2009, an outbreak of aseptic meningitis caused by coxsackievirus B5 (CVB5) occurred in China. Epidemiological investigations of this outbreak revealed that the proportion of severe cases (14/43, 33%) was higher than in other outbreaks associated with CVB5 in China. Phylogenetic analysis of the entire VP1 sequences demonstrated that the CVB5 isolates from the severe cases form a distinct lineage belonging to genogroup E with the Shandong isolates of 2009. A substitution of serine (S) to asparagine (N) at amino acid 95 in the VP1 region may be a major virulence determinant for the virus. Our findings suggest that this new lineage of CVB5 is circulating in China. Further genetic studies are needed in order to gain a better insight into the genetic variability of CVB5 isolates and the relationship with pathogenicity. [ABSTRACT FROM AUTHOR]

Cultivation for agricultural production often poses threats to nearby wetlands ecosystems in fertile landscapes. In this study, nematode ecological indexes were assessed through the main soil properties of the wetlands, farmlands, and edges of wetlands and farmlands in Jinchuan Wetland by the random sampling. Behavior and reproduction in Caenorhabditis elegans (C. elegans) exposed to the sampled waters were also examined. Stress proteins Hsp70 and Hsp90 were measured both in the living field samples of C. elegans and the lab-tested C. elegans. Our results suggested that disturbance to wetland ecosystems by nitrogen and phosphorus reduced nematode richness and proportions of bacterivore nematodes. Bacterivore nematode diversity and plant-parasitic ecological index were proven to be sensitive indicators of the ecological health of wetlands. Nematode Hsp70 were useful biosensors to monitor and assess the levels of nitrogen and phosphorus pollutions in wetlands. Furthermore, multi-level soil faunal assessments by canonical correspondence analysis showed that Jinchuan Wetland is threatened with non-point source pollution from nearby farmlands.

We identified 3 atypical Shigella flexneri varieties in China, including 92 strains with multidrug resistance, distinct pulse types, and a novel sequence type. Atypical varieties were prevalent mainly in developed regions, and 1 variant has become the dominant Shigella spp. serotype in China. Improved surveillance will help guide the prevention and control of shigellosis.

This paper describes the first isolation of a new Shigella flexneri serotype, designated 4s, in Beijing, China. Genotypic and phenotypic profiling suggests that this isolate is a clone of the S. flexneri serotype X variant reference strain. Of particular concern is the multidrug resistance exhibited by this isolate.