Breakthrough and New Projects for Reform of Household Registration System

Under the comprehensive deepening reform and promoting new urbanization,China launched a new round of reform of household registration system.Reform has a major breakthrough in five areas:to implement new urbanization strategy of human-centric,to achieve equalization of basic public services gradually,to break up land rights and rural migrants,to provide protection for family migrants,and to increase financial support by governments.But the reform still faces many difficulties,how to determine the conditions settled by city size is difficult to implement effectively,financial transfer payment system reform is facing enormous diffi culties,as well as the size of the urban population is diffi cult to determine etc.

基于树木年轮宽度的秦岭太白红杉(Larix chinensis)生长变化规律研究

采用相关性分析法、时间序列ARIMA模型及检验,探讨太白红杉BAI(Basal Areas Increment)与地形因子(海拔、坡度和坡向)的关系及其生长规律。结果表明:太白红杉平均BAI与海拔和坡度呈负相关关系,南坡BAI生长趋势较北坡增幅大;太白红杉第1次生长高峰出现在20a左右,大高峰约16 a^20 a左右出现一次,小高峰约4 a^6 a左右出现一次,历史最低值和最高值出现在1840年和1997年;太白红杉BAI与地形因子海拔和坡度呈较显著负相关关系,较适宜的海拔和坡度范围分别是在3 050 m^3 150 m和10°~20°;生长规律为幼龄太白红杉BAI处于快速增长的阶段,中龄后太白红杉BAI增速减缓,但整体生长趋势呈现较平稳上升的态势。