[Variations in soil enzyme stoichiometry and microbial nutrient limitations in Camellia oleifera plantations with different ages]. / ä¸åŒæž—é¾„æ²¹èŒ¶æž—åœŸå£¤é ¶åŒ–å­¦è®¡é‡ç‰¹å¾åŠå¾®ç”Ÿç‰©å »åˆ†é™åˆ¶å› ç´ .

The alteration of stand age instigates modifications in soil properties and microbial communities. Understanding the impacts of stand age on soil enzyme stoichiometry and microbial nutrient limitations in Camellia oleifera plantation is crucial for nutrient management. Taking C. oleifera plantation across four age groups (<10 a, 15-25 a, 30-50 a, >60 a) in a subtropical red soil region as test objects, we examined the response of soil enzyme stoichiometry and microbial nutrient limitations to change in stand age and analyzed the pathways for such responses. The results showed that, compared to that of stand age <10 a, enzyme C:N in the 15-25 a was increased and enzyme N:P was significantly reduced. Microbial biomass carbon (MBC), microbial biomass nitrogen (MBN), and microbial biomass phosphorus (MBP) exhibited a trend of initially decreasing and then increasing with stand age. MBN and MBN:MBP were significantly higher in the <10 a compared to that in the 30-50 a. MBC:MBN was significantly higher in the 30-50 a and >60 a compared to the <10 a and 15-25 a. Results of redundancy analysis revealed that soil nutrients, microbial biomass and their stoichiometry explained 92.4% of the variations in enzyme stoichiometry. Partial least squares path modeling (PLS-PM) results demonstrated that soil organic carbon (SOC) had a positive effect on microbial C limitation; MBN, MBN:MBP, MBC:MBP, SOC, and total nitrogen had a nega-tive overall effect on microbial P limitation, whereas soil C:N had a positive overall effect on microbial P limitation. There was a significant positive correlation between microbial C and P limitations. With increasing stand age, microbial nutrient limitation shifted from N and P limitation (<10 a) to C and P limitation (15-25 a, 30-50 a, >60 a).

[Evaluation and cumulative characteristics of heavy metals in soil-Uncaria rhynchophylla system of different functional areas].

Soil and Uncaria rhynchophylla in different functional areas were selected for the study,the content of heavy metals such as As, Cd, Cu, Cr, Pb, and Hg in soil and U. rhynchophylla was discussed, the characteristics of their accumulation in the U.rhynchophylla was analyzed, the contamination levels of heavy metals in soil in different functional areas was evaluated. The results showed that content of Cu, As, Pb and Cr in soil was being cropland>woodland>wasteland, content of Cd was being woodland>cropland>wasteland, content of Hg was being cropland>woodland>wasteland. According to quality standard of soil environment, soil Cd in woodland, cropland and wasteland all exceeded the state-level standards, soil Cd in woodland exceeded the secondary standard, soil Hg in cropland and wasteland all exceeded the state-level standards. According to technical conditions of green food producing area, soil Cd in woodland exceeded the limit value of standard. According to Green Trade Standards of Importing Exporting Medicinal Plants Preparations,the content of heavy metals of U.rhynchophylla in cropland,woodland and wasteland were correspond to the specification. From the single factor pollution index, the soil in woodland was polluted by Cd. From the comprehensive pollution index, the soils in different functional areas were not contaminated by heavy metals. The enrichment coefficient of heavy metals such as As, Cu, Cr, and Pb in hook of U.rhynchophylla was being wasteland>woodland>cropland, the enrichment coefficient of Cu in hook of U. rhynchophylla in wasteland was more than 1. Except Cu, the enrichment coefficient of other heavy metals was low.

Betatrophin Acts as a Diagnostic Biomarker in Type 2 Diabetes Mellitus and Is Negatively Associated with HDL-Cholesterol.

Objective. By assessing its circulating concentrations in type 2 diabetes mellitus (T2DM) patients, we aimed to explore the associations of betatrophin with various metabolic parameters and evaluate its diagnostic value in T2DM. Methods. A total of 58 non-diabetes-mellitus (NDM) subjects and 73 age- and sex-matched newly diagnosed T2DM patients were enrolled. Correlation analyses between circulating betatrophin levels and multiple metabolic parameters were performed. Receiver operating characteristic (ROC) curve analysis was used to assess the diagnostic value of betatrophin concentration in T2DM. Results. Circulating betatrophin levels were approximately 1.8 times higher in T2DM patients than in NDM individuals (median 747.12 versus 407.41 pg/mL, P < 0.001). Correlation analysis showed that betatrophin was negatively associated with high-density lipoprotein cholesterol (HDL-C) levels in all subjects. ROC curve analysis identified betatrophin as a potent diagnostic biomarker for T2DM. The optimal cut-off point of betatrophin concentration for predicting T2DM was 501.23 pg/mL. Conclusions. Serum betatrophin levels were markedly increased in newly diagnosed T2DM patients and further elevated in obese T2DM subjects. Betatrophin was negatively correlated with HDL-C levels. Our findings indicate that betatrophin could be a potent diagnostic biomarker for T2DM.