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Assessment of soil quality in different vegetation types of wetland ecosystems is essential for soil functioning, such as nutrient cycling and vegetation growth, particularly the maintenance of wetland ecosystem sustainability. Wetland degradation can extremely influence soil quality. However, prediction of soil quality in terms of soil quality index in wetland soils remains obscure. In this study with the fundamental goal to assess soil quality, we have intended to assemble a range of soil quality indicators to characterize the soil quality index (SQI). The minimum data set (MDS) from the Principal component analysis (PCA) was used to determine the SQI. With such objectives, three vegetation types: Robinia pseudoacacia community (tree), Tamarix chinensis community (bush), and Suaeda salsa community (grass) were selected in the Yellow River Delta wetland, eastern of China. A total of 108 soil samples [3 sites (tree, bush and grass)—3 field plots—3 replicates—4 soil depth layers: 0–10 cm, 10–20 cm, 20–40 cm, and 40–60 cm] were collected for laboratory analyses. This study showed that there were high variations in soil physical and chemical properties among the three sites. Soil organic carbon (SOC), silt, clay, and pH at tree site, total soil porosity (TSP), soil organic carbon (SOC), pH, and soil bulk density (SBD) at bush site, and total soil porosity (TSP), silt, and soil electronic conductivity (SEC) at grass site were retained in the MDS. SOC and TSP were the key soil quality indicators. The values of the SQI at 0–10 cm soil depth at all three sites (2.236, 0.895, and 2.573 respectively) were the highest compared with other soil depths, indicating the best soil quality in the upper soil layers (0–10 cm). The values of the SQI at 0–10 cm soil depth at both tree site and grass site were similar, and they were higher than those at bush site. At tree site, the values of the SQI decreased with increasing soil depth, which indicated that soil quality became worse with depth. At bush site, the values of the SQI decreased with increasing soil depth (0–40 cm), while the values increased at 40–60 cm depth, indicating better soil quality in the deeper soil layers (40–60 cm). At grass site, the values of the SQI at 10–20 cm and 40–60 cm soil depth were lower than those at 20–40 cm soil depth, indicating better soil quality at 20–40 cm soil depth. It is concluded that the SQI can be compared more accurately in different vegetation types of wetland ecosystems based on its simplicity and quantitative flexibility. These findings are of importance because the assessment of the SQI allows to quantify different vegetation effects on soil quality.

Understanding impacts of land use/cover (LULC) and climate change ecosystem services (ESs) is critical to human well-being. However, existing studies seldom determined the relative contributions of LULC and climate change to ESs from a geospatial perspective, and the impacts of different LULC conversions on ESs remain unclear. This study established a framework for distinguishing the relative spatial contributions of climate and LULC change to water yield, net primary productivity (NPP) and soil retention and applied it to Zhejiang Province. The results showed that all ESs showed an increasing trend from 2000 to 2020. Changes in water yield and soil retention were dominated by climate change, accounting for 75.22% and 77.69% of the total study area, respectively, while the changes in NPP were dominated by LULC changes, accounting for 82.70% of the total study area. We further quantified the impact of three major forms of LULC changes (urbanization, deforestation, and afforestation) on ESs in their respective regions. Deforestation and urbanization reduced NPP by 192 gC/m2 and 115.75 gC/m2, respectively, while afforestation increased NPP by 220.10 gC/m2. Afforestation reduced the water yield by 84.27%, while deforestation and urbanization increased it by 37.94% and 62.42%, respectively. Deforestation reduced soil retention by 38.28%, while urbanization and afforestation increased it by 3.91% and 63.28%, respectively. Five suggestions for improving ES management were proposed based on our results. This study can provide a detailed reference for decision-makers seeking sustainable ecosystem management strategies.

In this study, an innovative method was used to assess the spatial and temporal patterns of the hydrological connectivity in soil profiles in the Yellow River Delta wetland. In this method, field dye-tracing experiments conducted in the study area (i.e., large [LWa] and small communities [LWb] of Phragmites australis and Suaeda glauca [JP]) were considered, and the root-soil interface in the region and the status of the wetland degradation were analyzed. The results revealed that the index of hydrological connectivity (IHC) significantly changed both spatially and temporally. The high IHC values reaching a 0.392 ± 0.209 gradient were concentrated in the middle and western parts of the study areas. The spatial distribution of the high hydrological connectivity has been extremely fragmented since 2010. The LWb (severely degraded wetland) and JP (extremely degraded wetland) were found to be more seriously degraded than the LWa (moderately degraded wetland) in the study area. The changes in the IHC were positively correlated with the principal component (PC) values of the wetland degradation. The IHC is a novel indicator of the status of wetland degradation. Furthermore, the soil holding capacity, soil non-capacity porosity, and soil ventilation were relatively important for the changes in the IHC. Compared with the soil properties, the hydrological responses of the roots systems can be neglected at the root-soil interface. Based on our results, we propose an alternative wetland restoration solution for the Yellow River Delta wetland: 1) a seepage layer in the surface soils (0–10 cm), shallow ploughing treatment, and litter or straw return to the soil surface should be conducted to increase the hydrological connectivity of the soil surface; 2) reeds should not be reaped every year to remove the nutrients from this area; and 3) appropriate freshwater inputs should be strengthened.

Labile fractions of soil carbon pools are sensitive to environmental changes, which would influence the stabilization of soil carbon. However, it is unclear whether the dynamics of labile organic carbon (LOC) and soil organic carbon (SOC) are coupled and how they influence each other in coastal wetland. The present work investigated the trends of soil carbon fractions among mangrove and Spartina alterniflora communities with different stand ages (1, 5, 10, and 15 years), at Quanzhou Bay Estuary Wetland Nature Reserve, China. We found that SOC in a mangrove ecosystem increased over time, while there was no significant trend in S. alterniflora dominated ecosystems. The highest LOC of mangrove appeared in 5-year-old communities, and then decreased with stand age. In S. alterniflora communities, content of labile fractions increased with the stand age. These trends indicated different soil carbon dynamics when comparing mangrove and S. alterniflora ecosystems. The development of mangroves promoted accumulation of recalcitrant carbon, while S. alterniflora ecosystems contributed to an increase of labile carbon. This phenomenon is probably caused by the characteristics of vegetation and the hydrological conditions. Mangroves contribute more refractory organic carbon to the soil carbon pool, while accumulation of LOC in S. alterniflora communities may inhibit the stabilization of SOC. Our study on the relationship of LOC and SOC implies that complex interactions occur among soil carbon pools and environmental conditions in coastal wetlands, suggesting soil carbon models should take into account decoupled dynamics of LOC and SOC.

Ecosystems are severely damaged with rising global temperatures, the rapid increase in population and the continuous exploitation and utilization of natural resources. The selection of conservation priorities is of great significance to regional ecological security and sustainable development. Here we identified conservation priorities by balancing ecosystem services trade-offs and analyzed the spatiotemporal changes in ecosystem services. Water yield, soil conservation, carbon storage, habitat quality, and ecological recreation were quantified using the InVEST model. By comparing conservation efficiencies under each scenario, we found the conservation efficiencies of the conservation priorities for water yield, soil conservation, habitat quality, carbon storage, and ecological recreation to be 1.05, 1.76, 1.30, 1.37 and 1.41, respectively. The conservation efficiencies of ecosystem services were consistently greater than 1 during the years 2000–2015. The implementation of the Grain-for-Green Programme and increased rainfall have improved ecosystem services and our results are of great significance to regional ecological and environmental protection and the improvement of ecosystem services.

Background: Myeloperoxidase (MPO) anti-neutrophil cytoplasm autoantibody (ANCA)-associated vasculitis commonly causes life-threatening pulmonary alveolar hemorrhage or fibrosis. Only a limited number of candidate gene variants have been explored, but hitherto, are not widely confirmed. In the present study, we investigated the importance of energy homeostasis associated gene (Enho) mutations and adropin deficiency in the development of MPO-ANCA associated lung injury. Methods: We analyzed the peripheral blood mononuclear cells from 152 unrelated patients and 220 population-matched healthy individuals for genetic variations in Enho. Functional studies with adropin knockout (AdrKO) on C57BL/6J mice were also performed. Findings: Sequencing revealed six patients with p.Ser43Thr and that five patients shared Cys56Trp amino acid substitution in Enho. Serum concentration of adropin was significantly lower in patients than that of the healthy subjects (P