Precise quantifi cation of climate-growth relationships can make a major contribution to scientifi c forest management.However,whether diff erences in the response of growth to climate at diff erent altitudes remains ...Precise quantifi cation of climate-growth relationships can make a major contribution to scientifi c forest management.However,whether diff erences in the response of growth to climate at diff erent altitudes remains unclear.To answer this,264 trees of Larix kaempferi from 88 plots,representing diff erent altitudinal ranges(1000-2100 m)and tree classes were sampled and used to develop tree-ring chronologies.Tree-ring growth(TRG)was either positively(dominant)or negatively(intermediate and suppressed)correlated with climate in diff erent tree classes at diff erent altitudes.TRG was strongly correlated with growing season at low altitudes,but was less sensitive to climate at middle altitudes.It was mainly limited by precipitation and was highly sensitive to climate at low altitudes.Climate-growth relationships at high altitudes were opposite compared to those at low altitudes.TRG of dominant trees was more sensitive to climate change compared to intermediate and suppressed trees.Climate factors(annual temperatures;moisture,the number of frost-free days)had diff erent eff ects on tree-ring growth of diff erent tree classes along altitudinal gradients.It was concluded that the increase in summer temperatures decreased water availability,resulting in a signifi cant decline in growth rates after 2005 at lower altitudes.L.kaempferi is suitable for planting in middle altitudes and dominant trees were the best sampling choice for accurately assessing climate-growth relationships.展开更多
目的探讨基于Pearson相关系数的中国大陆地区护士工作环境与离职意愿的相关性。方法计算机检索PubMed、Embase、Ovid、ISI Web of Science、Springerlink、the Cochrane Library、Science Direct、Scopus、Google、CBM、VIP、万方数据库...目的探讨基于Pearson相关系数的中国大陆地区护士工作环境与离职意愿的相关性。方法计算机检索PubMed、Embase、Ovid、ISI Web of Science、Springerlink、the Cochrane Library、Science Direct、Scopus、Google、CBM、VIP、万方数据库和CNKI,对纳入研究的文献采用R软件进行meta分析。结果共纳入12篇文献。meta分析显示,工作环境总分与离职意愿的合并相关系数r为-0.3151(95%CI:-0.3505~-0.2955。2013—2015三年间工作环境与离职意愿相关程度变化不大。男护士工作环境与离职意愿的相关程度相对较低(r=-0.2198)。结论中国大陆地区医院工作环境与护士离职意愿存在中等程度负相关,近3年这种关系基本维持不变。医院管理部门应从工作环境方面着手,采取措施降低护士离职意愿,制定措施时应考虑性别的问题。展开更多
基金funded by Fundamental Research Funds of CAF (CAFYBB2022ZA00103)National Natural Science Foundation of China (General Program)(31971652)+1 种基金National Natural Science Foundation of China (32001308)Fundamental Research Funds of CAF (CAFYBB2022ZC001)
文摘Precise quantifi cation of climate-growth relationships can make a major contribution to scientifi c forest management.However,whether diff erences in the response of growth to climate at diff erent altitudes remains unclear.To answer this,264 trees of Larix kaempferi from 88 plots,representing diff erent altitudinal ranges(1000-2100 m)and tree classes were sampled and used to develop tree-ring chronologies.Tree-ring growth(TRG)was either positively(dominant)or negatively(intermediate and suppressed)correlated with climate in diff erent tree classes at diff erent altitudes.TRG was strongly correlated with growing season at low altitudes,but was less sensitive to climate at middle altitudes.It was mainly limited by precipitation and was highly sensitive to climate at low altitudes.Climate-growth relationships at high altitudes were opposite compared to those at low altitudes.TRG of dominant trees was more sensitive to climate change compared to intermediate and suppressed trees.Climate factors(annual temperatures;moisture,the number of frost-free days)had diff erent eff ects on tree-ring growth of diff erent tree classes along altitudinal gradients.It was concluded that the increase in summer temperatures decreased water availability,resulting in a signifi cant decline in growth rates after 2005 at lower altitudes.L.kaempferi is suitable for planting in middle altitudes and dominant trees were the best sampling choice for accurately assessing climate-growth relationships.
文摘目的探讨基于Pearson相关系数的中国大陆地区护士工作环境与离职意愿的相关性。方法计算机检索PubMed、Embase、Ovid、ISI Web of Science、Springerlink、the Cochrane Library、Science Direct、Scopus、Google、CBM、VIP、万方数据库和CNKI,对纳入研究的文献采用R软件进行meta分析。结果共纳入12篇文献。meta分析显示,工作环境总分与离职意愿的合并相关系数r为-0.3151(95%CI:-0.3505~-0.2955。2013—2015三年间工作环境与离职意愿相关程度变化不大。男护士工作环境与离职意愿的相关程度相对较低(r=-0.2198)。结论中国大陆地区医院工作环境与护士离职意愿存在中等程度负相关,近3年这种关系基本维持不变。医院管理部门应从工作环境方面着手,采取措施降低护士离职意愿,制定措施时应考虑性别的问题。