农村住房结构是决定地震灾害脆弱性的重要因素.对全国农村住房结构的差异性及其影响因素进行分析,是科学评估农村房屋脆弱性的基础.首先,根据2000 年全国第五次人口普查(五普)结果,将农村房屋分为“钢混”、“砖混”和“传统结构”(包括五普中住房墙体材料的“木、草、竹”和“其他”2 个类型)3 种结构类型,建立了全国县级尺度农村住房数据库,共2699 个区县.探讨农村住房结构的空间差异,遴选可能与之相关的因素进行相关分析,然后通过主成分分析和因子分析归纳出影响各类房屋空间分布的主要因素.结果表明,砖混结构是全国大部分农村地区最主要的住房结构类型,尤其在中东部地区的比例很高,而传统结构住房在西部地区所占比例较高(接近50%),影响这两种结构住房空间分布的主要因素是气候、地域文化和农村经济发展水平,农民收入水平越高,砖混结构房屋比例越高.钢混结构在农村房屋中所占比例普遍很低,东中部地区比西部、东北略高,气候、非农就业和镇域经济发展水平是影响其空间分布的主要因素.为了降低农村地区地震脆弱性,建议中国农村政策应以提高农民收入水平为主,并积极推动农村人口向小城镇聚集,还需要在农村地区逐步推广房屋抗震规范.

Housing structure is a principal factor of seismic vulnerability in Chinese rural areas. Therefore, analyses on the economic, geographic and cultural factors underlying the spatial differentiation of housing structures are very important for assessing the vulnerability of different regions. In this paper, a database of rural housing structures of 2699 counties all over China was established based on the Fifth National Census in 2000, where housing structures were divided into three types by the materials of bearing structures, i.e., reinforced concrete, brick-mixed and traditional (including houses made up of wood, grass, bamboo or other materials that are not standard). Then, the spatial patterns of rural housing structures were examined at both regional and county scales. It was found that, brick-mixed structure was the most important housing structure type in rural China, and the proportion of traditional housing structure was very high in the western region (close to 50%). Further analysis revealed that the distributions of traditional and brick-mixed structure houses were significantly influenced by the climate, rural economy and culture. The increase of incomes of rural citizens would prompt the shift of rural houses construction from traditional houses to brick-mixed ones. The proportion of the reinforced concrete structure houses in rural areas was generally low, but higher in the eastern and central regions than in the western region. Factors affecting the distribution of reinforced concrete structure houses include the climate, non-agricultural employment and township economy. It is suggested that the primary purpose of rural policies should aim to increase farmers’income to lower the degree of the seismic vulnerability in rural areas. Besides that, promoting the concentration of population in towns instead of in rural areas and gradually disseminating and applying the anti-seismic standards of house-building are also needed.