家户土地对洪涝灾害的经济响应研究湖南省洞庭湖区案例分析

通过对湖南省洞庭湖区家户经济与洪涝灾害关系展开的野外调查,和从行政门部与保险公司 获得的有关社会经济统计资料、案例资料,进行了衣户经济行为与土地经济行为的分析。结果表 明,家户对洪涝灾害的抵御能力主要受其经济能力的制约,土地一方面受到来自增加家户收入的压 力,另一方面受到来自必须给水以一定空间的压力,所以在尽量满足给水以一定空间的基础上,努 力提高单位土地的产出率,从而提高家户的经济收入,对这一湖区的农民家庭经济与洪涝灾害问题 的解决具有重要意义。     

稀土对沙田柚叶片营养和果实品质与产量的效应

试验结果表明,适量施用稀土可提高沙田柚树体对营养元素的吸收,促进养分平衡,从而可提高沙田柚座果率和产量,而且对柚果还有增糖降酸的效果。因此,适时适量施用稀土对提高沙田柚产量和品质均有积极的意义。     

洪涝灾害后城镇景观长距离输水系统水文风险评估

对输水系统运作过程存在风险采取准确评估,可有效维护洪涝灾害后城镇景观设施完整性.该文提出一种基于MS-AR模型的长距离输水系统水文风险评估方法,首先分析输水节点结构重要性与网络结构抗毁性的耦联关系,推算平均节点结构重要度,明确节点对系统损坏贡献水平,利用节点结构重要度离散性质表示输水系统网络结构抗毁性,获取长距离输水系...     

人工BSCs对稀土尾砂理化性质及抗蚀性的影响

以赣州市定南县岭北镇一座离子型稀土矿尾砂为研究对象,通过采集现场生物土壤结皮与尾砂,采用碎皮接种法在尾砂上培育人工生物土壤结皮(BSCs),以不接种BSCs的尾砂作为对照组,对比分析人工BSCs对离子型稀土矿尾砂的改良作用.在结皮发育300d后,分析了结皮下层尾砂的pH值,容重,有机质含量,全量和速效养分含量,机械组成...     

PARAMETER UNCERTAINTY IN RAINFALL-RUNOFF MODELING FOR POLDER SYSTEM DESIGN1

ABSTRACT: An approach is developed for incorporating the uncertainty of parameters for estimating runoff in the design of polder systems in ungaged watersheds. Monte Carlo Simulation is used to derive a set of realizations of streamflow hydrographs for a given design rainstorm using the U. S. Soil Conservation Service (SCS) unit hydrograph model. The inverse of the SCS curve number, which is a function of the antecedent runoff condition in the SCS model, is the random input in the Monte Carlo Simulation. Monte Carlo realizations of streamfiow hydrographs are used to simulate the performance of a polder flood protection system. From this simulation the probability of occurrence of flood levels for a particular hydraulic design may be used to evaluate its effectiveness. This approach is demonstrated for the Pluit Polder flood protection system for the City of Jakarta, Indonesia. While the results of the application indicate that uncertainty in the antecedent runoff condition is important, the effects of uncertainty in rainfall data, in additional runoff parameters, such as time to peak, in the hydraulic design, and in the rainfall-runoff model selected should also be considered. Although, the SCS model is limited to agricultural conditions, the approach presented herein may be applied to other flood control systems if appropriate storm runoff models are selected.     

长江流域洪灾与生态破坏的关系浅析:Ⅱ生态破坏导致洪灾加剧

与长江１９５４ 年洪灾相比较,１９９８ 年洪灾具有“中水量、高水位、大灾害”的特征。流域内原始森林的过量采伐、大量湖泊的消亡、河道的普遍淤塞等生态系统的破坏引起了长江产流、汇流、洪水调蓄、行洪等水文条件的严重恶化。这是长江流域洪灾频繁,灾情加重的主要原因。     

外源稀土在根际与非根际土壤中的存在形态

采用根际袋法研究了稀土在春小麦根际土壤与非根际土壤中存在形态的差别.结果表明,外源稀土进入土壤后,在根际土壤与非根际土壤中主要以残渣态形式存在,各形态含量的大小顺序为:残渣态>碳酸盐结合态>可交换态>铁锰氧化物结合态>有机质结合态.小麦根系活动明显影响根际土壤中的稀土存在形态,根际土壤中的可交换态和铁锰氧化物结合态含量明显大于非根际土壤中的含量,而碳酸盐结合态有所下降,有机质结合态无明显变化.     

FLOOD DAMAGES IN CHANGING FLOOD PLAINS: A FORENSIC‐HYDROLOGIC CASE STUDY1

ABSTRACT: Hydraulic modification of flood plains by human activity is the primary cause of rising flood damages throughout the world. As flood‐plain hydraulic roughness increases, so does the water level for a fixed flow rate. This raises the flood damage associated with a flood of given return period, and thus, magnifies the flood risk. This article presents an approach that integrates climatic, hydrologic, and hydraulic principles and presents models to discern the probable causes of flood damage in a basin that undergoes flood‐plain development. The article documents key factors that govern flood damage and presents a case study that illustrates the principles of forensic hydrology in an impacted flood plain. The study demonstrates flood level rise caused by hydraulic alteration of a flood plain between 1969 and 1995 and apportioned the increased water level among agricultural and structural factors located in the study area.     

Fiji's worst natural disaster: the 1931 hurricane and flood

At least 225 people in the Fiji Islands died as a result of the 1931 hurricane and flood, representing the largest loss of life from a natural disaster in Fiji's recent history. This paper explores the causes of disaster and the potential for recurrence. The disaster occurred because a rare event surprised hundreds of people—especially recently settled Indian farmers—occupying highly exposed floodplains in north‐west Viti Levu island. The likelihood of a flood disaster of such proportions occurring today has been diminished by changed settlement patterns and building materials; however, a trend towards re‐occupancy of floodplains, sometimes in fragile dwellings, is exposing new generations to flood risks. The contribution of this paper to the global hazards literature is set out in three sections: the ethnicity, gender and age of flood fatalities; the naturalness of disasters; and the merit of choice and constraint as explanations for patterns of vulnerability.     

加强国土规划建设与城市防灾的协同性分析

我国经济持续发展主要体现之一就是大规模的基础工程、道路交通和城市建设。近年来,各种灾害频繁发生,造成了巨大的人身和财产损失,也给"国土规划建设"和"城市防灾规划"工作提出了更迫切更严峻的挑战。我国拥有广大面积的洪泛区[2],洪灾是制约我国社会和经济可持续发展的重要因素;我国又是淡水资源极度缺乏的国家,雨水是淡水,应变灾害为资源。调整区域土地的使用性质和格局,国土规划建设是今后一个时期内科学发展、可持续发展的基础,做好国土规划建设刻不容缓。把国土规划建设结合其它城市灾害提出具体的措施,整体提高我国城市防灾规划水平,以达到节约投入,节省时间,根治水患、长期受益的目的。