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Earthworms modulate carbon and nitrogen cycling in terrestrial ecosystems, but their effect may be compromised by the deposition of pollutants from industrial emissions. However, studies investigating how deposited compounds affect the role of earthworms in carbon cycling such as litter decomposition are lacking, although the interactions of earthworms and deposited compounds are important for understanding the impact of pollutants on ecosystems and the potential of earthworms in bioremediation. We performed a 365‐day in situ litterbag decomposition experiment in a deciduous (Quercus variabilis) and coniferous (Pinus massoniana) forest in southeast China. We manipulated nitrogen (N), sodium (Na), and polycyclic aromatic hydrocarbons (PAHs) as model compounds during litter decomposition with and without earthworms (Eisenia fetida). After one year, N, Na, and PAH all slowed down litter mass loss, with the effects of Na being the strongest. By contrast, E. fetida generally increased litter mass loss, and the positive effects were uniformly maintained irrespective of the type of compounds added. However, the pathways to how earthworms increased litter mass loss varied among the compounds added and the two forests studied. As indicated by structural equation modeling, earthworms mitigated the negative effects of deposited compounds by directly increasing litter mass loss and indirectly increasing soil pH and microbial biomass. Overall, the results indicate that the acceleration of litter mass loss by earthworms is little affected by deposited compounds, and that earthworms have the potential to mitigate negative impacts of pollutants on litter decomposition and ecosystem processes. [ABSTRACT FROM AUTHOR]

• Significant differences in the responses of hydrodynamics, water quality and aquatic habitats to connectivity changes. • The connectivity threshold under multi-targets determined based on the water environment response is more accurate. • The optimal connectivity threshold is of great significance for solving wetland environment ecological degradation. The quality of the water environment of wetlands is closely related to the changes in hydrologic connectivity, so wetland responses to changing connectivity exhibit a range of optimal connectivity values. Identifying these ranges of values is of great significance for wetland ecological restoration. Current studies mostly determine the hydrologic connectivity ranges based on a single target, even though connectivity simultaneously affects multiple water environment targets. Hence, the optimal hydrologic connectivity should be determined by accounting for multiple targets. With the Baiyangdian Wetland as the study area, we developed a method to model how the water environment responded to changes in hydrologic connectivity from three perspectives: hydrodynamics, water quality, and aquatic habitat. To do so, we used the BP neural network model and a non-dominated sorting genetic algorithm to calculate the hydrologic connectivity values in a context with multiple targets. We found that under the optimal hydrodynamic target, the integral index of connectivity (IIC) threshold was [0.23, 0.61] and the probability connectivity (PC) threshold was [0.32, 0.68]; under the optimal water quality target, the IIC threshold was [0.42, 0.70] and the PC threshold was [0.48, 0.82]; under the optimal aquatic habitat target, the IIC threshold was [0.38, 0.69] and the PC threshold was [0.35, 0.71]; and under the comprehensive optimization target, the IIC threshold was [0.48, 0.64] and the PC threshold was [0.51, 0.73]. These ranges of values will help wetland managers determine the optimal ecological water releases to meet the ecosystem quality targets. [ABSTRACT FROM AUTHOR]

Focuses on the values of senior women intellectuals in China. Description of senior women intellectuals; Cultural and psychological quality of Chinese women intellectuals; Value of afforded career and family; Factors considered by the women as social status determinants.

A two-year field experiment was conducted to assess the influence of subsoiling (SS), two passes of rotary tillage (2RT), two passes of rotary tillage + subsoiling (2RTSS), and zero tillage (ZT) on soil physical properties and maize grain yield in Latosolic red soil of Southern China in a randomized complete block design with three repeats. Results showed that, SS recorded lowest soil bulk density (1.41 g cm-3 ), soil penetration resistance (1.81 MPa), soil gravimetric water content (21.12%), and volumetric water content (29.19%), resulting in highest soil porosity (47.36%) at 0-40 cm soil depth. Highest plant, ear height, ear length, ear weight, number of rows per ear, and number of grains per row were observed under SS. Also, maximum grain yield 7.37 ton ha-1 (9.81%), dry matter, harvest index, and 1000-grain weight were recorded under SS. Overall, SS improved soil physical properties and facilitated highest maize yield and yield components, and therefore, SS could be adopted as a strategy for higher productivity leading to a sustainable agricultural system under the changing climatic conditions. [ABSTRACT FROM AUTHOR]

• The present study reported the prevalence of Fasciola spp. in snails from large-scale regions of China. • In China, climate and topography could affect the Fasciola spp. infection in snails. • A highly positive correlation between snails and animal infection was found in central and eastern China. • Infected snails could be an indispensable risk factor for fasciolosis transmission. Fasciolosis is a zoonotic disease as 600 million animals have been infected, and 180 million people are at risk of the infection in the world. Snail as the intermediate host of Fasciola is an essential and important factor in the transmission of fasciolosis, while its potential risk for transmission has not been studied. In this study, 3561 snails collected from large-scale regions of China were examined by nest-PCR method. A total of 345 snails were positive for Fasciola spp. , with an overall prevalence of 9.7%. Prevalence in central and southern China, characterized by a subtropical monsoon climate, was relatively low (8.0%), while a high infection rate (36.9%) was found on the plateau area (altitude > 500 m). In combination with previous findings, the study showed a highly positive correlation between snails and animal infection in central and eastern China, thus indicating that infected snails could be an indispensable risk factor for fasciolosis transmission. Epidemiological surveillance of snails will help assess the risk of fasciolosis in humans or ruminants, which promotes future prevention of this zoonotic disease. [ABSTRACT FROM AUTHOR]

Phytochemical investigation on Hemiphragma heterophyllum led to the isolation of two new compounds, heterophyllumin A (1) and heterophylliol (3), along with nine known compounds, (‒)-sibiricumin A (2), iridolactone (4), jatamanin A (5), dihydrocatalpolgenin (6), 25-hydroperoxycycloart-23-en-3β-ol (7), 24-methylenecycloartanol (8), (+)-pinoresinol (9), hexadec-(4Z)-enoic acid (10), and 9,12, 15-octadecatrienoic acid (11). Their structures were elucidated on the basis of detailed spectroscopic analyses and by comparison with literature data. Further, the structure of compound 3 was unambiguously confirmed by single-crystal X-ray analysis. Some of those compounds showed moderate activity in the α-glucosidase inhibition assay. [ABSTRACT FROM AUTHOR]

Aboveground consumers can shape belowground processes in brown-food webs of forests by converting litter into faeces. Woodlice are one of the important aboveground consumer groups driving the dynamics of belowground soil. Although considerable data on litter decomposition exists, the indirect effects of woodlice (different qualities of faeces) on litter decomposition need to be explored further. In this study, we assessed the influence of isopods ( Armadillidium vulgare ) and its by-products (three contrasting qualities of faeces) on the decomposition of broad-leaf and needle litter via soil incubation. Litter mass loss, soil microbial biomass and soil extracellular enzyme activities treated with different isopod by-products were determined in six-month laboratory incubations. The results showed that after incubation, the indirect effect of fauna (faeces) did not significantly increase broad-leaf litter decomposition. However, faeces of isopods fed on high-quality legume litter significantly increased needle litter decomposition. The effects of isopod faeces on microbial activities were significant: most of the soil microbial biomass and extracellular enzyme activities increased significantly compared with non-faeces treatments in the soil of broad-leaved and coniferous forests; and high-quality faeces strengthened the correlation of litter mass loss with peroxidase and phenol oxidase in coniferous forest. The result suggests that faeces with higher concentrations of nitrogen and labile carbon can mediate the decomposition of refractory materials like lignin and phenolic compounds, which might be highly relevant for the litter decomposition process in ecosystems with high macrofauna abundance. This study infers that the indirect effect of isopods (faeces) on litter decomposition depends on the quality of the litter they consumed and the type of decomposing litter. Isopods indirectly accelerate the nutrient-poor litter decomposition process by converting high-quality litter into faeces. As such, the negative effects of litter recalcitrance on microbial decomposition in mixed forests are indirectly alleviated. [ABSTRACT FROM AUTHOR]

Creating a soil habitat is the first step to manage soil health for long‐term soil quality and output. This means using soil management methods that lessen the soil uproar. An experiment was established in 2016 and 2017 on a middle term (7 years) consistent tillage method in typical Latosolic red soil of Southern China to access the effects of four treatments: subsoiling (SS), two passes of rotary tillage (2RT), two passes of rotary tillage + subsoiling (2RTSS), and zero tillage (ZT), on soil organic carbon, soil total nitrogen, soil biological activities (bacteria, fungi, actinomycetes, urease, catalase, and phosphatase), and maize grain yield. The results showed that mean SOC, total N, biological activities, and maize grain yields were affected significantly (p < 0.05) by tillage methods. Compared with SS, 2RT, and 2RTSS, ZT had higher SOC, total N, soil bacteria, and soil actinomycetes in the 0–40 cm soil depth. The highest levels of fungi, urease, catalase, and phosphatase were recorded under SS in the 0–40 cm soil depth. Average maize grain yield of 7.37 ton/ha (9.81%) was recorded under SS compared to under ZT. Overall, we conclude that SS could be adopted as a promising soil management method for soil health, quality, and productivity resulting in a sustainable agricultural system. [ABSTRACT FROM AUTHOR]