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Crown width (CW) is an important individual tree variable commonly used to assess tree vigor and the production efficiency of stands. However, our understanding of the effects of climate and the combined effects of climate with competition on the variation of CW remains unknown. Therefore, this study developed CW models by nonlinear mixed-effects (NLME) to explore these effects. Data were obtained from Korean pine (Pinus koraiensis Siebold and Zucc.) plantations in five forestry agencies in northeastern China. The results showed that stand basal area (BA), height to crown base (HCB), isothermality (BIO3), and annual precipitation (BIO12) were significantly related to the variations of CW. CW increased with increasing BIO12, while decreased with increasing BA, HCB, and BIO3. The hierarchical partitioning (HP) analysis showed that the relative importance of BIO3 was larger than BA, HCB, and BIO12. In addition, we found that competition altered the variations of CW responses to climate. Competition, tree size, and climate CW model (CC-CWM) performed the best performance in model fitting and prediction accuracy. Therefore, CC-CWM was selected to predict CW under future climate change. By comparing the eleven sampling methods with eighteen sample sizes, it was reasonable to select six medium-trees to estimate the random effect parameters. Our study provides evidence of the effects of climate and the combined effects of competition and climate on the variations of CW, potentially useful for the development of rational and scientific forest management decisions under future climate changes. [ABSTRACT FROM AUTHOR]

Soil environmental quality assessment traditionally focuses on a single objective. Therefore, related results only reflect the pollution of the assessment objective and ignore the interaction and relationships between soil, ecology, and human health. In this study, we collected and filtered data about heavy metal content (Cr, Pb, Cd, Hg, As, Cu, Zn, and Ni) in city soils from more than 1000 published papers. Spatial multi-criteria decision-making theory was used to establish the combined evaluation model of soil environmental quality using the geochemical accumulation, ecological risk, non-carcinogenic risk, and carcinogenic risk indexes. Our results showed that the pollution degree and elements causing most pollution were significantly different when these different methods were used for assessment. The proposed framework was able to unify the overall pollution trend in regional soil environmental quality assessment and could output more robust and reasonable assessment results of soil, ecology, and human health. The random forest model was used to analyze the potential sources for excessive accumulation of heavy metal elements in soils, and the results showed that the main potential sources were the proportion of secondary industry and urbanization rate, each with an average contribution ratio of 20%. This study provides comprehensive and specific information for the prevention and control of soil heavy metal pollution in China. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to examine the overlaps between the Diagnostic and Statistical Manual-5 (DSM-5) Personality Disorders (PDs) in a high-risk clinical population and to explore a transitional model for implementing DSM-5 PDs.Method: A sample population of 982 outpatients with at least one diagnosed PD was selected from 3,075 outpatients of the Shanghai Mental Health Center. The diagnostic process comprised of a personality diagnostic questionnaire and a structured clinical interview.Results: 685 (22.3%) patients were diagnosed with at least one of six PDs (antisocial, avoidant, borderline, narcissistic, obsessive-compulsive, and schizotypal) under the alternative DSM-5 model for personality disorders proposed in Section III of the DSM-5. Nearly 20.3% of the subjects with PD met criteria for at least two PDs (of the 685 PD patients/6 PD model). Cluster and principal component analyses suggest a transitional model for the 7 specific PD categories (among the 722 PD patients, the overlapping rate was 24.1%) will be more appropriate for PD diagnosis in China.Conclusions: Using the simplified PD categories in the alternative DSM-5 model for personality disorders will reduce the overlaps in PD diagnoses in Chinese psychiatric practice, and should be preferred over the DSM-5 PD diagnostic system. [ABSTRACT FROM AUTHOR]