Losses and destabilization of soil organic carbon stocks in coastal wetlands converted into aquaculture ponds.

Coastal-wetlands play a crucial role as carbon (C) reservoirs on Earth due to their C pool composition and functional sink, making them significant for mitigating global climate change. However, due to the development and utilization of wetland resources, many wetlands have been transformed into other land-use types. The current study focuses on the alterations in soil organic-C (SOC) in coastal-wetlands following reclamation into aquaculture ponds. We conducted sampling at 11 different coastal-wetlands along the tropical to temperate regions of the China coast. Each site included two community types, one with solely native species (Suaeda salsa, Phragmites australis and Mangroves) and the other with an adjacent reclaimed aquaculture pond. Across these 11 locations we compared SOC stock, active OC fractions, and soil physicochemical properties between coastal wetlands and aquaculture ponds. We observed that different soil uses, sampling sites, and their interaction had significant effects on SOC and its stock (p < .05). Reclamation significantly declined SOC concentration at depths of 0-15 cm and 15-30 cm by 35.5% and 30.3%, respectively, and also decreased SOC stock at 0-15 cm and 15-30 cm depths by 29.1% and 37.9%, respectively. Similar trends were evident for SOC stock, labile organic-C, dissolved organic-C and microbial biomass organic-C concentrations (p < .05), indicating soil C-destabilization and losses from soil following conversion. Soils in aquaculture ponds exhibited higher bulk density (BD; 11.3%) and lower levels of salinity (61.0%), soil water content (SWC; 11.7%), total nitrogen (TN) concentration (23.8%) and available-nitrogen concentration (37.7%; p < .05) than coastal-wetlands. Redundancy-analysis revealed that pH, BD and TN concentration were the key variables most linked with temporal variations in SOC fractions and stock between two land use types. This study provides a theoretical basis for the rational utilization and management of wetland resources, the achievement of an environment-friendly society, and the preservation of multiple service functions within wetland ecosystems.

[Effects of Straw and Biochar Amendments on Characteristics of Soil Fungal Community and Organic Carbon Pool in Jasminum sambac Garden].

In order to elucidate the changes in the soil fungal community and soil organic carbon components of a Jasminum sambac garden after straw and biochar application, we measured the organic carbon components and soil fungal community of the 0-15 cm soil layer in a J. sambac garden, which was divided into a control group, straw treatment group, and biochar treatment group. The carbon pool management index （CPMI） was also calculated. The results showed that the diversity of the soil fungal community was decreased after straw and biochar application, and the structure of dominant fungal genera was changed in each treatment. The soil fungal community structure in the biochar treatment was significantly different from that in the straw treatment and control groups. Redundancy analysis （RDA） showed that soil fungal community structure was mainly affected by soil bulk density, C∶N, salinity, and TN. Secondly, compared with that in the control group, soil labile organic carbon （LOC） in the straw treatment group was significantly increased by 87.44% （P<0.05）, whereas soil dissolved organic carbon （DOC） and microbial biomass carbon （MBC） in the biochar treatment group were significantly increased by 22.27% and 23.17% （P<0.05）, respectively. Further, compared with that in the control group, the carbon pool activity （L） under straw treatment was significantly increased （P<0.05）, and the carbon pool index （CPI） under biochar treatment was significantly increased （P<0.05）. Spearman correlation analysis showed that the distribution characteristics of soil organic carbon active components were regulated by the dominant fungi. FUNGuild functional prediction results showed that saprophytic and its facultative nutritional fungi had an important impact on soil organic carbon active components and carbon pool management index after straw and biochar application.

Enhanced Fenton-like process over Z-scheme MoO3 surface decorated with Fe2O3 under visible light.

Photocatalysts consisting of Z-scheme heterojunctions are commonly used in wastewater treatment due to their exceptional reactivity in photocatalysis and highly efficient visible-light utilization. In this work, Fe2O3-decorated MoO3 rods were synthesized through a two-step method and their photodegradation of methylene blue (MB) was evaluated. The Fe2O3/MoO3 rods were characterized by XRD, SEM, micro-Raman, XPS, UV-Vis DRS, and PL to investigate their structural, morphological, and optical properties. The results indicate that the photodegradation efficiency of Fe2O3/MoO3 improved through a reduction in the gap energy and persistence of a 1D hexagonal prism structure. The degradation rate of MB was enhanced from 31.7 to 91.5% after irradiation for 180 min owing to electron-hole separation and Fenton-like process. Formation of the OH radical is a key factor in the photodegradation reaction and with the addition of H2O2 the efficiency can further improve via a Fenton-like mechanism. Furthermore, the Z-scheme mechanism concurrently delineated. The Fe2O3/MoO3 rod composites were also found to retain high photocatalytic efficiency after being reused five times, which may be useful for future applications.

[Characteristics of Soil Carbon, Nitrogen, Phosphorus, and Ecological Stoichiometry in Vegetable Fields and Orchard in the Coastal Area of Fuzhou].

The soil ecological stoichiometric characteristics of different agricultural land use types have a certain indicator function for characterizing the level of soil nutrient supply and are of great significance to the management of nutrient resources in farmland ecosystems. In order to reveal the soil carbon (C), nitrogen (N), and phosphorus (P) contents and their ecological stoichiometric characteristics in different vegetable fields and orchard agricultural land use types, this study took vegetable fields (taro field and jicama field) and orchards (citrus tree orchard, watermelon field, and pear tree orchard) as the research objects in the coastal area of Fuzhou City. The contents of soil C, N, and P and their ecological stoichiometric characteristics in different vegetable fields and orchard agricultural land uses were measured and analyzed. The soil C and N contents were in the order of orchard>vegetable field (P<0.05). The C content in the citrus tree orchard was the highest (4.44 g·kg-1), and the N content in the watermelon field was the highest (1.46 g·kg-1). The soil P content was vegetable field>orchard (P<0.05), and the jicama field had the highest P content (0.19 g·kg-1). The soil carbon and nitrogen ratio (C/N), carbon and phosphorus ratio (C/P), and nitrogen and phosphorus ratio (N/P) were orchard>vegetable field (P<0.05). Among them, the citrus tree orchard had the highest C/N (7.40) and C/P (61.43), and the watermelon field had the highest N/P (10.27). Soil N content was significantly and negatively correlated with bulk density and conductivity (r=-0.49, r=-0.28, P<0.05), and there was a significant and positive correlation with soil water content (r=0.61, P<0.05). C/P and C/N were significantly and positively correlated with SOM (r=0.71, r=0.64, P<0.01). In the process of crop planting and management in the coastal area of Fuzhou City, it is necessary to reasonably add nitrogen fertilizer to compensate for the N limitation, and slow-release nitrogen fertilizer is better for promoting the sustainable supply of nitrogen nutrients in the growth and development of crops.

Effects of combined applications of straw with industrial and agricultural wastes on greenhouse gases emissions, temperature sensitivity, and rice yield in a subtropical paddy field.

The incorporation of post-harvest crop straw and application of industrial and agricultural wastes to paddy soils increase rice crop yields and soil fertility. However, the impacts of combined applications of straw and waste products on greenhouse gas (GHG) emissions and global warming potential (GWP) of paddy soils are unclear. Therefore, we conducted a field experiment in subtropical rice in China to test the effects of applications of straw, straw+biochar, straw+shell slag, straw+gypsum slag, straw+silicon, and straw+steel slag on rice yields, GWP, and greenhouse gas emission intensity (GHGI). The results showed that, compared to the control, cumulative emissions of carbon dioxide (CO2) from paddy soils were 15.2, 16.9, and 36.6 % lower following application of straw+steel slag, straw+silicon, and straw+gypsum, respectively, and cumulative emissions of methane (CH4) were 5.0 and 62.1 % lower following application of straw+steel slag and straw+gypsum, respectively. Meanwhile, relative to the addition of straw alone, application of straw+steel slag and straw+gypsum reduced GHG emissions largely due to reductions in CO2 emissions, further declining the GWP of CO2 and GHGI. In addition, temperature sensitivity (Q10) of CO2 emissions was highest following application of straw+silicon and lowest following application of straw+gypsum. There were no treatment effects on mean dissolved porewater concentrations of CO2, CH4, or nitrous oxide (N2O) and soil emissions of CO2 were negatively correlated with mean dissolved concentrations of CO2, CH4, and N2O. Rice yields were reduced following application of straw+gypsum and unaffected by the other treatments. Thus, relative to the addition of straw alone or control, we suggest the combined application of straw+steel slag may improve the sustainability of paddy rice production, because it reduces GWP, while maintaining yields.

Effects of slag and biochar amendments on microorganisms and fractions of soil organic carbon during flooding in a paddy field after two years in southeastern China.

Incorporating amendments of industrial waste such as biochar and steel slag in cropland has been used to enhance the storage of soil organic carbon (SOC) while sustaining crop production. Short-term laboratory and field studies have identified important influences of biochar on active SOC fractions associated with soil microbial activity in paddy soils, but the long-term effects remain poorly understood. To address these knowledge gaps, we examined the effects of slag, biochar, and slag+biochar treatments on total SOC concentration, active SOC fractions and soil microbial communities in a paddy field two years after incorporation. Across both two seasons, the addition of slag, biochar, slag+biochar increased soil salinity by 26-80%, 1.3-37% and 42-79%, and also increased soil pH by 0.8-5.7%, 2.1-2.4% and 4.0-6.3%, respectively, relative to the control. SOC concentration was higher in the slag, biochar, and slag+biochar treatments across both rice seasons by 4.3-5%, 0.5-17% and 4.3-7%, respectively. Soil C-pool activity and C-pool management indices in the late paddy season were significantly lower in the slag+biochar treatment than the control by 26.3 and 21.3%, respectively, indicating that the amendments contributed to the stability of SOC. The C concentrations of the biochar and slag amendments affected bacterial abundance more than fungal abundance and affected C cycling. Our study suggests that combined slag and biochar amendments may increase bacterial abundance that may maintain SOC storage and reduce the abundances of potential SOC decomposers in key functional genera, indicating strong coupling relationships with changes of soil properties such as salinity, pH, and SOC concentration. These outcomes due to the amendments (e.g. slag+biochar) may increase microbial C-use efficiency and support the stability of active SOC fractions, with opportunities for long-term C sequestration.

Obstetric and Gynecologic Outcomes after the Transvaginal Repair of Cesarean Scar Defect in a Series of 183 Women.

STUDY OBJECTIVE: To analyze retrospectively the effect of hysteroscopy combined with transvaginal repair on the cesarean section diverticulum (CSD) and explore the clinical significance of this procedure. DESIGN: Retrospective study. SETTING: University-affiliated hospital and a gynecology hospital. PATIENTS: A total of 183 patients with scar diverticulum after cesarean section were recruited from the Southern Medical University Affiliated Maternal & Child Health Hospital of Foshan and Shenzhen In Vitro Fertilization Gynecological Hospital. INTERVENTIONS: In this study, we reported a surgical method for repairing uterine scar through uterine therapy and explored its clinical efficacy and pregnancy outcome. MEASUREMENTS AND MAIN RESULTS: The time of operation, volume of bleeding, and duration of hospitalization were recorded. The size of the scar diverticulum and the remaining myometrium were examined by B-mode ultrasonography before and after the operation. The length of the menstrual cycle and pelvic pain were recorded during follow-up to check the recovery of patients after surgery. The pregnancy of patients with pregnancy needs was recorded to check the pregnancy outcome. All 183 patients successfully completed the repair of the transvaginal uterus scar diverticulum with the help of a hysteroscopy examination. The mean (± standard deviation) operation time was 58.61 ± 18.56 minutes. The mean blood loss was 36.97 ± 22.32 mL. The mean hospital stay was 6.08 ± 1.89 days. In 57.14% of patients, the CSD completely disappeared, whereas the volume of CSD shrank by at least 50% in 88.95% of patients. The mean menstrual period of patients after surgery was 7.72 ± 2.68 days, which was significantly shorter than that recorded preoperatively (13.45 ± 3.69 days) (t = 19.62, p = .00). The pelvic pain disappeared in 81.08% of the patients. The mean postoperative thickness of the remaining muscular layer was 5.30 ± 1.27-mm, which was significantly higher than the preoperative value of 2.25 ± 0.92-mm (t = 28.21, p = .00). The mean postoperative thickness of the remaining muscular layer of patients with improved menstrual cycle was 5.40 ± 1.27-mm, which was significantly higher than the thickness of 4.88 ± 1.11-mm in patients without improved menstrual cycle (t = 2.31, p = .025). A total of 124 patients attempted to become pregnant, 83 of whom were successful. The pregnancy rate was as high as 66.95%, which included 2 scar pregnancies, 4 ectopic pregnancies, and 87 intrauterine pregnancies. No uterine rupture occurred. CONCLUSION: The transvaginal repair of the uterine diverticulum improved the symptoms and probability of a successful pregnancy effectively. This process is a surgical procedure to increase the thickness of the residual uterine muscle wall effectively.

Association between angiotensinogen T174M polymorphism and ischemic stroke: A meta-analysis.

BACKGROUND: Numerous studies have evaluated the association between the angiotensinogen (AGT) T174M polymorphism and ischemic stroke(IS) risk. However, the specific association is still controversial. MATERIALS AND METHODS: In order to explore this association more deeply, we performed a meta-analysis. All of the relevant studies were identified from PubMed, Embase, and Chinese National Knowledge Infrastructure database up to October 2014. Statistical analyses were conducted with STATA 12.0 software. Odds ratio (OR) with 95% confidence interval (CI) values were applied to evaluate the strength of the association. RESULTS: Six studies with 1290 cases and 1125 controls were included. No significant variation in IS risk was detected in any of the genetic models in the overall (MM vs. TT: OR = 1.64, 95% CI = 0.51-5.28; MT vs. TT: OR = 0.93, 95% CI = 0.66-1.31; dominant model: OR = 1.08, 95% CI = 0.69-1.72; recessive model: OR = 0.61,95% CI = 0.20-1.91). Taking into account the effect of ethnicity, further stratified analyses were performed. The results showed that AGT gene T174M polymorphism might be associated with IS risk in Asians (MM vs. TT: OR = 3.28, 95% CI = 1.79-6.02; recessive model: OR = 0.31, 95% CI = 0.17-0.57). CONCLUSION: In conclusion, the AGT T174M polymorphism may be a susceptible predictor of the risk of IS in Asians. Further, large and well-designed studies are needed to confirm this conclusion.

Analysis of 265 autopsies of sudden death in children.

OBJECTIVE: To investigate the causes of death and characteristics of sudden death in children and to offer scientific bases for prevention and cure, and medicolegal expertise of sudden death in children. MATERIAL: A retrospective study was carried out on the 265 cases of sudden death in children under 14 years old from 1960 to 2003 in three key hospitals of Haikou city, Hainan Province, China. RESULT: Of the 265 cases, 164 were male and 101 were female (1.6:1). Most of them were babies aged 1 month-1 year (37.0%). The three most common causes of sudden death in children were diseases such as lobular pneumonia, aspiration pneumonia and viral pneumonia. CONCLUSION: Most of the reported cases of sudden death in children were babies aged 1 month approximately <1 year and males were much more than females in the ratio of 1.6:1. The main diseases causing sudden death were the diseases of the respiratory system, especially pneumonia.

Extraosseous osteogenic sarcoma.

Extraosseous osteogenic sarcoma is a very rare malignant neoplasm. Out of the more than 400 cases of soft tissue sarcomas on file in our hospital, only 2 were extraosseous osteogenic sarcomas. Both were situated in the thigh. The first case was initially diagnosed as a hematoma and treated by marginal excision. The diagnosis of high-grade osteosarcoma primarily arising in soft tissue was made from histopathologic examination. Radiotherapy of 60 Gy in 30 fractions was given postoperatively. The second patient, primarily diagnosed as having a soft tissue sarcoma, was treated by wide excision. The final pathologic report was high-grade extraosseous osteogenic sarcoma. Adjuvant chemotherapy was given postoperatively. Both patients are alive without local recurrence and distant metastasis at postoperative 90-month and 107-month follow-up, respectively.