"深圳-巴彦浩特"地理样带土地利用与水旱灾害研究

在建立1990-2000年“深圳-巴彦浩特“地理样带水旱灾害数据库的基础上,结合样带1995、2000年两期的土地利用数据,分析了样带水旱灾害的区域差异,及其与样带土地利用时空格局的关系.结果表明,样带水旱灾害呈现较强的南北差异,北方以旱灾为主,南方以水灾为主;土地利用结构对样带水旱灾害有较强的影响,土地利用类型复杂的县市有较高的水旱灾害发生率,而土地利用类型单一的县市则受水旱灾害影响较小.水灾主要出现在样带南部多种土地利用类型混杂的县市,特别是城镇建设用地比例较高的地区,水灾相对更为频繁;旱灾在缺乏灌溉水源且以耕地和草地为主要土地利用类型的区域发生频率较高.

A study on land use and flood-drought disasters in Shenzhen-Bayanhaote geographic sampled zone in China

Based on the flood and drought disasters database for period from 1990 to 2000 and the land use data of 1995 and 2000 in the Shenzhen-Bayanhaote sampled zone,this paper analyzes the regional disparity of flood and drought disasters and it's relation with spatiotemporal pattern of land use in the sampled zone.The results indicate that:(1)The land use changes were evidently affected by rapid urbanization.The percentage of farmland has decreased from 34.2% to 17.26%,while the urban land has expanded from 0.09% in 1995 to 0.28% in 2000,and the bare land has increased from 7.57% to 18.2% in the same period.(2)The flood and drought disasters in the south are obviously different from those in the north of the sampled zone.Drought disasters mainly take place in the north,while flood disasters mainly in the south.(3)Land use structure has a strong influence on the flood and drought disasters in the sampled zone.There is higher incident rate of the flood and drought disasters in the counties where the land use types are complex.Flood disasters mainly take place in south counties of the sampled zone where the land use types are various and farraginous,especially in the area which has a high ratio of urban land,flood disasters occur more frequently.Drought disasters have high incident rate in areas that are lack of water and mainly are farmland and grassland.