摘要目的 应用地理信息系统(GIS)分析重庆市居民户非碘盐的空间分布规律.方法 建立2001-2010年重庆市各区(县)非碘盐数据库,利用GIS技术,通过ArcGIS 9.3软件分析重庆市居民户非碘盐的空间分布和空间白相关性.结果 2001-2006年重庆市居民户非碘盐率波动在2.35％ ～ 5.78％,2007-2010年非碘盐率降到2.00％以下.2001-2006年重庆市居民户非碘盐全局空间自相关分析结果:Moran's Ⅰ指数分别为0.145578、0.078801、0.108033、0.091957、0.127749、0.214302(Z值分别为3.066275、1.977321、2.541619、2.309972、2.900446、3.874203,P均＜0.05),在整个重庆市区域非碘盐空间格局呈现非随机分布,存在明显的聚集区域;局部空间自相关分析结果:确定丰都、涪陵为重庆市非碘盐的高危区域(P均＜ 0.05),另于2001、2005、2006年确定出垫江、渝北、江北、武隆、巴南5个区(县)为高危区域(P均＜ 0.05),所有高危区域的非碘盐分布均表现为正相关.2007-2010年重庆市非碘盐全局空间自相关分析结果,Moran's Ⅰ指数分别为0.018361、0.016186、0.040769、-0.059691(Z值分别为1.093310、0.787361、1.071811、-0.583820,P均＞0.05),在整个重庆市区域非碘盐空间格局呈现随机分布；局部空间自相关分析结果:存在局部高危地区,垫江、丰都非碘盐分布表现为正相关,江津、石柱表现为负相关.结论 重庆市居民户非碘盐的空间分布由2006年以前的聚集分布演变成2007年以后的随机分布,但存在高值区域,后者应作为监测重点.

abstractsObjective To analyze the spatial distribution characteristics of non-iodized salt at household level based on geographic information system (GIS) in Chongqing.Methods The database of non-iodized salt at county level from 2001 to 2010 was established in Chongqing.By using GIS technology,the spatial distribution and spatial autocorrelation were analyzed by ArcGIS 9.3 software.Results The rate of non-iodized salt was fluctuated between 2.35％-5.78％ during 2001-2006 and the rate was reduced to less than 2.00％ after 2007.The result of spatial autocorrelation analysis on non-iodized salt from 2001 to 2006 indicated that Moran's Ⅰindex was 0.145578,0.078801,0.108033,0.091957,0.127749,0.214302,respectively(Z value was 3.066275,1.977321,2.541619,2.309972,2.900446,3.874203,respectively,all P ＜ 0.05).The spatial distribution of non-iodized salt had marked spatial cluster through Chongqing region from 2001 to 2006.The result of local spatial autocorrelation analysis from 2001 to 2006 indicated that Fengdu and Fuling were two high-risk areas(all P ＜ 0.05).Dianjiang,Yubei,Jiangbei,Wulong and Banan were also confirmed as high-risk areas in 2001,2005 and 2006(all P ＜ 0.05).The results also indicated that the distribution of non-iodized salt in the seven high-risk areas was positively correlated.The result of spatial autocorrelation analysis on non-iodized salt from 2007 to 2010 indicated that Moran's Ⅰ index was 0.018361,0.016186,0.040769,-0.059691,respectively (Z value was 1.093310,0.787361,1.071811,-0.583820,respectively,all P ＞ 0.05).The spatial distribution of non-iodized salt was at random on the whole from 2007 to 2010.However,there were four local high-risk areas.The distribution in Fengdu and Dianjiang was positively correlated,while that in Jiangjin and Shizhu was negatively correlated.Conclusions The distribution of non-iodized salt at households level in Chongqing is changed from spatial distribution before 2006 to random distribution after 2007,but there are high value areas,which should be taken as the focus of monitoring.