Vulnerability And Disaster Risk Of Disaster Bearing Body Based On Land Use

Against the background of global warming and sea level rise,natural disasters of all kinds occur frequently,and huge losses caused by typhoons are experienced every year from coastal areas to inland areas.The Beibu Gulf Economic Zone is one of the regions with frequent typhoons in China.Carrying out research on vulnerability and disaster risk assessment of disaster bearing bodies in the Beibu Gulf Economic Zone can provide technical support for optimizing land use layout and strengthening disaster prevention and mitigation in the Beibu Gulf Economic Zone.This paper takes 38counties and districts in the Beibu Gulf Economic Zone as the research unit,and selects indicators such as land use type,elevation,slope,average wind speed,process rainfall,road network density,per capita GDP,disposable income of urban residents,urbanization rate,local financial income,etc.from 2010 to 2020;The combined weight method,VSD model,comprehensive index method and other methods are used to calculate the hazard of the disaster-causing factors,the vulnerability of the disaster-bearing body and the disaster risk of the disaster-bearing body in each district and county,and the impact factors of the disaster risk of the disaster-bearing body in each district and county are calculated through the barrier model;Finally,the GIS technology is used to analyze the time and space of the evaluation results and present the final results.The final research results are as follows:Select the typhoon path density,average wind speed and process rainfall to build the hazard assessment index system of the disaster cause.The research shows that in2010,the high risk area and low risk area were the main areas,with the area accounting for 30.13%and 26.52%respectively;In 2015,the area of the lower hazard area was the largest,reaching 16709.37km~2;In 2020,it will be dominated by low-risk areas,covering an area of 23916.22km~2,accounting for 33.31%.In terms of spatial distribution pattern,in 2010 and 2015,the level of dangerous areas decreased gradually from the southern coastal areas to the inland areas in a ring;In 2020,hazardous areas at all levels are mainly distributed in blocks,but some areas along the southern coast are still in high-risk areas.Select natural attribute indicators such as land use type,elevation,slope,road network,river network,and proportion of cultivated land area from three aspects of exposure,sensitivity and adaptability of the disaster-bearing body,and socio-economic indicators such as population density,regional financial income,regional gross domestic product,urbanization rate,per capita GDP,residents’disposable income,number of beds in medical institutions,number of students in ordinary secondary schools,number of students in ordinary primary schools;Build a VSD evaluation model for the vulnerability of the disaster-bearing body to evaluate the vulnerability of the disaster-bearing body.The evaluation results are as follows:In 2010 and 2015,the area of high vulnerability zone was mainly 40352.2 km~2 and 27977.5 km~2,respectively;In 2020,it will be dominated by lower vulnerable areas,accounting for 35.52%of the area.The spatial distribution of vulnerability levels is relatively obvious,with higher vulnerability levels in the northwest and southern coastal areas and lower vulnerability in the southeast.Couple the hazard of the disaster causing factor and the vulnerability of the disaster-bearing body to conduct a spatial-temporal analysis of the disaster risk,and use the obstacle model to calculate the impact factors of the disaster risk.The results of the research on the disaster risk in the Beibu Gulf region are as follows:in 2010,high-risk areas dominated,accounting for 46.79%of the area;In 2015,it will focus on lower risk areas and high risk areas;In 2020,it will focus on lower risk areas;The disaster risk of Beibu Gulf has a downward trend over time.The area of risk areas at all levels has four different trends of change:first falling,then rising,then falling,continuing to rise,and continuing to fall.Low-risk areas fall first and then rise,lower risk areas and medium-risk areas rise first and then fall,higher risk areas continue to rise,and high risk areas continue to decline.The typhoon disaster risk gradually weakened from the coastal areas to the inland areas.In 2010 and 2015,the disaster risk level gradually weakened from the three coastal cities to the inland areas,and in 2020,it continued to decline from the central area to the east and west.Combined with the hazard of the disaster causing factors and the main obstacle factors of the exposure degree of the disaster-bearing body,the main influencing factors of the disaster risk are wind speed,land use type,river network density,proportion of cultivated land area and slope.