Assessment of soil quality in an arid and barren mountainous of Shandong province, China.

Forest soils are important components of forest ecosystems, and soil quality assessment as a decision-making tool to understand forest soil quality and maintain soil productivity is essential. Various methods of soil quality assessment have been developed, which have occasionally generated inconsistent assessment results between soil types. We assessed the soil quality of five communities (herb, shrub, Quercus acutissima, Pinus thunbergii, and Q. acutissima-P. thunbergii mixed plantation) using two common methods of dry and barren mountains in the Yimeng Mountain area, China. Sixteen soil physical, chemical and biological properties were analysed. The soil quality index was determined using the established minimum data set based on the selection results of principal component analysis and Pearson analysis. Silt, soil total phosphorus (P), soil total nitrogen (N), L-leucine aminopeptidase, acid phosphatase and vector length were identified as the most representative indicators for the minimum data set. Linear regression analysis showed that the minimum data set can adequately represent the total data set to quantify the impact of different communities on soil quality (P < 0.001). The results of linear and non-linear methods of soil quality assessment showed that the higher soil quality index was Pinus forest (0.59 and 0.54), and the soil quality index of mixed plantation (0.41 and 0.45) was lower, which was similar to the herb community (0.37 and 0.44). Soil quality was mostly affected by soil chemical properties and extracellular enzyme activities of different communities, and the different reasons for the low soil quality of mixed plantations were affected by soil organic carbon (C) and total C. Overall, we demonstrate that the soil quality index based on the minimum data set method could be a useful tool to indicate the soil quality of forest systems. Mixed plantations can improve soil quality by increasing soil C, which is crucial in ecosystem balance.

Transoral Endoscopic Thyroidectomy Vestibular Approach Versus Endoscopic Thyroidectomy Via Areola Approach for Patients With Unilateral Papillary Thyroid Carcinoma: A Retrospective Study.

BACKGROUND: Endoscopic thyroidectomy via areola approach (ETA) has been widely used in thyroidectomy for many years as it can effectively avoid a scar in the neck. Transoral endoscopic thyroidectomy vestibular approach (TOETVA) is newly applied and has gained popularity quickly. This study is to compare the safety and effectiveness of TOETVA and ETA. MATERIALS AND METHODS: A total of 95 patients who underwent TOETVA or ETA with unilateral papillary thyroid carcinoma were enrolled in this study from March 2019 to February 2020. The basic information (such as gender, age), intraoperative hemorrhage, postoperative drainage volume, hospital durations, intraoperative and postoperative complications, operative time, central lymph node dissection time, total number of central lymph nodes, and number of metastatic central lymph nodes were compared. RESULTS: The operative time of the TOETVA group was significantly longer than the ETA group (148.11±19.78 vs. 135.90±12.77 min, P<0.05). However, the result was opposite when central lymph node dissection time was compared (10.31±2.93 vs. 12.48±3.55, P<0.05). TOETVA had an advantage on total number of central lymph nodes over ETA (7.82±3.35 vs. 5.26±2.45, P<0.05). No differences were found between the 2 groups on other data. CONCLUSION: TOETVA and ETA have the similarity on surgical safety and effectiveness. TOETVA has its advantage on central lymph node dissection and might be a reasonable alternative for ETA and open surgery in the future.