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The Dongguashan skarn copper deposit can be considered as the product of the transport‐chemical reaction coupling process of ore‐forming materials (for example, complexes of copper) in discrete, parallel fractures in a porous medium system. A mathematical model of metallogenesis has been established and the accurate analytical solutions for depicting the transport of ore‐forming materials have been worked out. In establishing the model of metallogenesis and working out the analytical solutions, the following aspects have been taken into consideration: (1) advective transport along fractures; (2) diffusion and longitudinal mechanical dispersion of ore‐forming materials (solutes) along the fracture axis; (3) diffusion of ore‐forming materials from the fractures to the wall media; (4) adsorption of ore‐forming materials on the surface of wall‐rock matrices; (5) adsorption of ore‐forming materials within the wall‐rock matrices; (6) reduction of the concentrations of solutes due to the chemical reactions between ore fluids and wall‐rock matrices and the precipitation of ore‐forming materials. [ABSTRACT FROM PUBLISHER]

Abstract: Background and aim: The concept of nurse‐led care (NLC) was not familiar in China. This study was designed to evaluate the clinical effectiveness and cost‐effectiveness of NLC versus rheumatologist‐led care (RLC) in Chinese patients with rheumatoid arthritis (RA). Methods: Patients of either gender (aged ≥18 years) with RA were enrolled at Wenhai Central Hospital, China (January 2015 to December 2015). The participants were then randomized to NLC or RLC. Outcomes of both the groups were compared in terms of effectiveness by measuring the Disease Activity Score 28, visual analogue scores pertaining to pain and fatigue, and duration of morning stiffness. Costs associated with resource use for RA were assessed and compared between both groups. Results: A total of 214 RA patients in 2 groups (n = 107 in each group) were enrolled and analysed. Improvements in clinical outcomes (disease activity, pain, fatigue, and morning stiffness) over 12 months were significantly greater in the NLC group compared to RLC (P < 0.001). Overall, costs associated with resource use were higher in the RLC group compared to the NLC group (P < 0.05). Conclusions: Our preliminary finding suggested that RA patients managed by NLC compared to RLC may have better clinical outcomes and more cost‐effective care in China. [ABSTRACT FROM AUTHOR]

• Decomposition rate and effects were measured in field and laboratory experiments. • Measured soil properties and PLFAs for decomposition at different salinities and inundation environments. • Decomposition rate was correlated with water quality and fungal microbe content. • Leaf litter may control carbon cycling and energy flow in estuary ecosystems. • Artificially elevating wetland nutrient content may mitigate negative human impact. Decomposition of halophyte litter may considerably influence carbon cycling and energy flow in estuarine ecosystems. We examined water quality parameters, soil properties, and soil phospholipid fatty acid (PLFA) contents from the Yellow River Estuary, China, to investigate Phragmites australis and Suaeda glauca litter decomposition dynamics. Surface soils (0–10 cm) under three different salinity conditions were collected from six plots. Results showed that the litter decomposition rate of S. glauca (k = 0.0063) was significantly (p = 0.032) higher than that of P. australis (k = 0.0024). Litter decomposition rate had a significant (p < 0.01) relationship with water compositional parameters (water dissolved oxygen, temperature, chemical oxygen demand, and NH 3 -N). According to the results of our surface soil analysis, in plots with 1% salinity, values for total soil PLFAs, bacterial PLFAs, Gram-negative PLFAs, and fungal PLFAs were all higher after 270 days than after 120 days. Fungi were the principal microbial group responsible for leaf litter decay. Changes in the nutrient utilization of litter may result in changes in the allocation of resources for growth and reproduction, which suggests that artificial elevation of wetland nutrient content may mitigate the negative human impacts associated with climate change. This study demonstrated the effects of biotic (litter types, activities of microbial organisms) and abiotic (salinity, inundation) variables on halophyte litter decomposition in Yellow River Delta wetlands. [ABSTRACT FROM AUTHOR]

Urban forests have been shown to be efficient for reducing air pollutants especially for particulate matters (PMs). This study aims to reveal the PM blocking capacity of two common artificial landscape species, Sabina chinensis and Liriodendron chinense and to investigate spatial-temporal heterogeneities by estimating the vegetation collection velocity of coarse (PM10) and fine particles (PM2.5) during different seasons and heights. PM concentration and meteorological data were collected on both leeward and windward sides of trees during the daytime in both summers and winters from 2013 to 2015. Concentration and meteorological monitors were installed at three heights, bottom (1.5 m), middle (3.5 m), and top (5.5 m) of the canopy. The results showed: During daytime, the collection velocity changed and PM2.5 collection velocity was much higher than that of PM10. Furthermore, the maximum collection velocities of L. chinense and S. chinensis occurred at 14:00–16:00 both in summer and winter. Moreover, the collection velocity had a positive correlation with wind speed and temperature. The blocking capacities of L. chinense and S. chinensis varied from season to season, and the concentrations of particulate matter indicate the middle canopy of both species as the most effective part for TSP blocking. Furthermore, these two species are more effective blocking in PM2.5 than PM10. The blocking capacity of S. chinensis is generally better. The vegetation collection is the major process of PM removal near the ground and sedimentation was not taken into consideration near the ground. [ABSTRACT FROM AUTHOR]

• Decomposition rates were measured among different salinity and inundation conditions. • Suaeda glauca decomposed faster than Phragmites australis in Yellow River Delta wetland. • Faster litter decomposition rate occurred in inundation environment. • The combined effect of salinity and inundation can significantly accelerate S. glauca litter decomposition rate. • Environment parameters and litter quality can interact and in turn affect the decomposition rate during the decay process. The main factors controlling plant litter decomposition rates are litter quality and environmental factors. We investigated how different salinity and inundation conditions influence the decomposition rate and how litter quality affects dynamic change during the decomposition process in the Yellow River Delta wetland in northeastern China. To do this, we designed a field experiment using the litter bag method to study two selected dominant halophyte species (Phragmites australis and Suaeda salsa). We found litter decomposed faster when inundated across a range of salinities. Both the water chemical oxygen demand and NH 3 -N concentration were inversely correlated with salinity. The ratio of nitrogen to phosphorous showed an upward trend during the process of decomposition. The decomposition rate increased during the later stage of the process. Under inundation conditions, the decomposition rate of only S. salsa showed a positive correlation with salinity. The study results suggest that moderately higher salinity would increase anaerobic decomposition owing to the combined effect of salinity and inundation. The implications of our findings may be used to further assess the impact of environmental parameters and litter quality on the decomposition rate in estuarine wetland and can help determine a strategy for wetland reparation and remediation. [ABSTRACT FROM AUTHOR]

Salt marshes are changeable and important ecosystems that currently face various threats, including global climate change and human activities. The influence of these factors can result in the degradation of salt marshes. Tidal creeks, which are an important source of nutrients and other substances for salt marsh vegetation, play an important role in the health of salt marshes. In this study, the morphological characteristics of tidal creeks and the characteristics of two typical plants, Suaeda glauca (SG) and Phragmites communis (PC), in the Yellow River Delta, China were investigated to determine the effect of tidal creeks on these plants. Aerial photography and field measurements of tidal creeks were carried out from May to July 2018 in the study area. At the same time, nine line-intercepts were set in the vertical direction of tidal creeks to investigate plants. The results showed that different grades of tidal creek exerted no significant influence on the growth of either S. glauca or P. communis. However, unlike grade, the size of a creek and the distance from it had marked effects on these plants. The cross-sectional area of a tidal creek had a significant positive impact on the density of S. glauca (r = 0.39, p = 0.02). For P. communis , the depth of a tidal creek had a strong correlation with this species' density (r = 0.51, p = 0.04) and height (r = 0.63, p = 0.01). Meanwhile, there was a negative relationship between the distance from tidal creeks and the height of S. glauca (r = −0.52, p = 0.02). Conversely, the height (r = 0 0.90, p = 0.00) and density (r = 0.62, p = 0.01) of P. communis were positively affected by its vertical distance from tidal creeks. We found that the subtidal zone near a tidal creek was more conducive to the recovery and growth of S. glauca , and that areas further away from a tidal creek, located in the intertidal and subtidal zones, were more conducive to the recovery and growth of P. communis. The parameters associated with tidal creeks in the subtidal zone (cross sectional area 4.55 m2, distance 0–10 m) were beneficial for the growth of S. glauca. For P. communis , relevant features in the intertidal and subtidal zones (depth 0.40–0.45 m, distance 20–60 m) are useful. Our results suggest that attention should be paid to the effects of size and distribution of tidal creeks during the process of salt marsh restoration. This work also provides practical guidance for the restoration of native salt marshes in China. • Depth of a tidal creek had a strong positive correlation with P. communis. • Cross-sectional area of a tidal creek had a significant positive impact on S. glauca. • Both S. glauca and P. communis had obvious correlations with the distance from tidal creeks. • Areas located in the subtidal zone near a tidal creek was more conducive to S. glauca. • Relevant features in the intertidal and subtidal zones are useful for P. communis. [ABSTRACT FROM AUTHOR]