Study On Safety Evaluation And Safeguard Technology Of Rural Domestic Water In Guizhou Mountainous Areas

Domestic water is the basic needs of people's livelihood.The karst area in southwestern China is the most concentrated area of global karst distribution,and it is also the “squatting land” of China's economic development.The economic development of rural areas is even more backward,and the rural water security is still far behind the other economically developed areas.Guizhou mountainous area is the most typical.The rural social and economic development in the mountainous areas of Guizhou is relatively backward.In the past,the rural water conservancy facilities were under-represented,and the waste water was not discharged to the standard.In recent years,with the continuous increase in water conservancy construction investment,rural living safety has improved,but the water safety standards are relatively loose and the foundation is weak,and the safety hazards are still serious.There is a relative lack of research on rural domestic water safety in Guizhou mountainous areas.Therefore,40 districts and counties under the jurisdiction of Qiandongnan Prefecture,Anshun City,Southwest Guizhou and Guiyang City are selected,which have great differences in natural environment and social and economic development,and uses the PSR model to construct an evaluation index system for living water in Guizhou mountainous areas.Combined with the PLS structural equation model,the rural residential water safety in the study area is quantitatively reflected from the county level,and the macro factors clearly affect the main influencing factors of rural domestic water safety in Guizhou mountainous areas.From the economic-society-environment dimension,this study analyzes the driving types and influencing reasons of rural domestic water safety in the study area,and tests the water quality of typical villages from the village level to understand the water quality safety status and main problems in Guizhou mountainous areas,and proposes several safe water security technologies and countermeasures that it is suitable for mountainous areas.The main conclusions are as follows:(1)The impact of state on rural domestic water safety is much greater than pressure and response,indicating that the natural situation and water resources of mountainous areas are not very ideal and are the main influencing factors.The proportion of rural population,disposable income of rural residents,the added value of primary industry to GDP,the density of surface river network,the average annual groundwater resources,the proportion of karst area,forest coverage,surface undulation,average slope,and the proportion of villages treated with domestic garbage concentration,the proportion of villages treated with concentrated domestic sewage,the proportion of tap water with purified drinking water source,and the proportion of unprotected well water and spring water have a greater impact on rural domestic water safety.The water quality of typical village water is mainly affected by the number of coliform bacteria,nitrate nitrogen and total bacteria.(2)From the distribution of the comprehensive safety index of rural domestic water in the study area in 2016,the districts and counties that are safer and critically safe account for 10% and 57.5% of the total number of districts and counties respectively,and the districts and counties with unsafe and extremely unsafe levels respectively.It accounts for 20% and 12.5% of the total number of districts and counties,most of which are at a critical safety level,followed by unsafe,and the overall safety of rural domestic water in the study area is less than ideal.Overall,Guiyang City,Qiandongnan Prefecture,Anshun City,and Southwest Guizhou Province have gradually deteriorated.Only Nanming District,Yunyan District,Baiyun District and Guanshan Lake District of Guiyang City are safer,and other districts and counties are critically safe,unsafe or extremely unsafe.(3)From the distribution of safety index of each sub-system of rural domestic water safety in the study area in 2016:The pressure safety index accounts for 10%,17.5%,35%,17.5%,and 20% of the districts and counties of the V-I level.The four districts and counties with the pressure safety index at the V level are located in Guiyang City,and the highest in Yunyan District is 0.3,the eight districts and counties with pressure safety index at level I are located in southwestern Guizhou,and the lowest in Wangmo County is 0.044.In districts and counties where the development of rural areas is better,the safety index of rural domestic water use pressure is higher.The number of districts and counties with state safety index at V-I level accounted for 20%,7.5%,22.5%,32.5%,and 17.5%,respectively,from Congjiang County to the highest of 0.288,and Anlong County with a minimum of 0.113.The rural household water use safety index of all districts and counties in southeastern Guizhou is higher,followed by Anshun City,Guiyang City,and Southwest Guizhou Province.In areas with better natural conditions and richer precipitation,the safer state of rural domestic water use is better.The number of districts and counties with a response safety index at the V-I level accounted for 17.5%,27.5%,22.5%,25%,and 7.5%,respectively,the highest in the Yunyan area was 0.267,and the lowest in the Wangmo County was 0.046.The rural life water safety response safety index varies widely.The response index is related to the level of rural economic and social development.The districts and counties with better development,the response is higher.Therefore,the response index of the districts and counties in Guiyang City is higher in the four cities and states.This should also be the rural domestic water in all districts and counties of Guiyang City.The main reason for the relatively high overall safety.(4)Reasons for the formation of rural domestic water safety and driving types from the economic-society-environmental dimension analysis,the districts and counties in the study area can be divided into three categories: balanced drive,economic and social drive,and environmental drive.In the balanced driving type,the rural economic water safety effected by social and environmental impacts are not much different,accounting for 50% of the total number of districts and counties in the study area.The areas with greater economic,social and environmental impacts are divided into balanced driving type I,affecting The smaller areas are divided into Equilibrium drive type II,which account for 22.5% and 27.5% of the total number of districts in the study area.The economic and social-driven regions are mainly affected by the backward development of economic and social development,which accounts for 25%;the environmentally-driven regions divide the regions with better social and economic development into environmentally driven subtypes,which are mainly affected by geographical environment.The impact of complex and fragile accounts for 25%.The safety of rural domestic water in most districts and counties of the study area is mainly affected by the backward economic and social development and the uneven environmental quality.(5)In response to the problems of rural water safety,propose technical measures for water purification treatment,domestic sewage treatment,culture and excrement disposal,strengthen water conservancy facilities construction,water resources protection and management,improve environmental management,promote ecological protection and regional industry integration development,and develop festivals watertype agriculture,strengthening the environmental protection awareness of rural residents and other environmental protection.