Sloping Farmlands Conversion to Mixed Forest Improves Soil Carbon Pool on the Loess Plateau.

Vegetation restoration is considered a potentially useful strategy for controlling soil erosion and improving soil organic carbon (SOC) in arid and semiarid ecosystems. However, there is still debate regarding which vegetation restoration type is the best choice. In this study, four vegetation restoration types (i.e., grasslands, shrubs, forests and mixed forests) converted from sloping farmlands were selected to explore the SOC variation among the four types and to investigate which soil factors had the greatest effect on SOC. The results showed while the magnitude of effect differed between vegetation restoration type, all studied systems significantly increased SOC and labile organic carbon contents (p < 0.01), soil nutrients such as total nitrogen (TN) (p < 0.01), available nitrogen (AN) (p < 0.01), total phosphorus (TP) (p < 0.05) and available phosphorus (AP) (p < 0.05), soil enzyme activities such as phosphatase (p < 0.01), soil microbial biomass carbon (MBC) (p < 0.05), and basal respiration (BR) (p < 0.05), but had significant negative correlationswith polyphenol oxidase (p < 0.05). However, the effects of vegetation restoration of farmland converted to natural grasslands, shrubs, forests and mixed forests varied. Among the types studied, the mixed forests had the largest overall positive effects on SOC overall, followed by the natural grasslands. Soil nutrients such as N and P and soil microbial activities were the main factors that affected SOC after vegetation restoration. Mixed forests such as Robinia pseudoacacia and Caragana korshinskii are the best choice for farmland conversion on the central of the Loess Plateau.

Metabolomic Analysis Of Human Follicular Fluid: Potential Follicular Fluid Markers Of Reproductive Aging.

OBJECTIVE: To assess the difference in the metabolomics profiles of follicular fluid between older and younger reproductive-aged women. METHODS: The retrospective study was conducted at the Centre of Reproduction and Genetics, Affiliated Hospital of Shandong University of Traditional Chinese Medicine, Jinan, China and comprised patient data related to the period between July and October 2015. Follicular fluid was obtained from male-factor infertility women aged 28-35 years as the younger group A, and those aged 35-42 years as the older group B. The subjects were undergoing in vitro fertilization / intracytoplasmic sperm injection and were retrospectively analysed by ultra-performance liquid chromatography-high-resolution mass spectrometry. The fragments were structurally identified using debris' information obtained from fragmented ion scans to identify the different compounds. RESULTS: Of the 55 cases studied, 28(51%) were in group A with a mean age of 29.57 ± 2.92 years, and 27(49%) were in group B with a mean age of 39.19±2.95 years. Compared with the group A, four types of compounds, hormones, licithin, lysophospholipids, and protein degradation fragments, were expressed significantly differentially in group B (p<0.05 each). Nicotine glucuronide and phosphatidylcholine were found only in Group B follicular fluid. CONCLUSIONS: The components of follicular fluid and relative contents were found changed with ageing.

Influence of soil and water conservation measures on soil fertility in the Beijing mountain area.

Soil and water conservation (SWC) measures can be adopted to conserve soil and water and improve soil fertility. The degree to which SWC measures improve soil fertility is affected by the type of SWC measure, soil type, climate, etc. The purpose of this study was to study the effect of the main SWC measures implemented in the Beijing mountain area on soil fertility. Six runoff plots, including a fish pit (fallow) (FPF), fish pit (Platycladus orientalis L. Franco) (FPP), narrow terrace (fallow) (NTF), narrow terrace (Juglans regia L.) (NTJ), tree pan (Juglans regia L.) (TPJ), and fallow land (FL), were established to analyze the differences in soil fertility in the Beijing mountain area. Soil samples were collected in 2005 and 2015 from the six runoff plots. Soil particle size; soil total nitrogen (TN), total phosphorous (TP), total potassium (TK), alkali-hydrolysable nitrogen (Ah-N), available P (Av-P), and available K (Av-K); and soil organic matter (SOM) were measured. The soil integrated fertility index (IFI) was calculated. The results showed that the soil nutrient content and IFI significantly decreased from 2005 to 2015 in the FL plot and significantly increased in the five runoff plots with SWC measures. Compared to the other runoff plots with SWC measures, the FPP plot more significantly improved the soil nutrient content and IFI. The TN, Ah-N, Av-K, SOM, and IFI in the FPP plots increased by 98%, 113%, 61%, 69 and 47%, respectively, from 2005 to 2015. The IFI for the FPP, NTJ, and TPJ exceeded the average IFI of the farmland soil in the study region. The results indicated that the combination of engineering practices and vegetative measures effectively improved soil fertility. These results may be helpful for selecting SWC measures, land-use planning and monitoring and assessing soil fertility.