Research On Water Quality Of Landscape Water In Guangzhou City Park And Study On Water Purification Effect Of Submerge Plants

Most of the construction of urban park landscape water bodies are mainly static water bodies with poor fluidity and prominent eutrophication.However,high-quality and low-carbon ecological landscape water bodies have become an important part of urban ecological environment construction.At present,emergent water and Floating Plant are mainly planted in park water bodies,and the water quality purification and maintenance effects are not significant.Submerged plants have strong ability to repair water bodies and high ecological value,which is more effective for constructing low-carbon ecological water bodies.Therefore,in order to find out the water quality status of landscape water bodies in major parks in Guangzhou city and the application status of submerged plants in park landscape water bodies,this study selected 6representative landscape water bodies in Guangzhou city parks as research objects,aiming at improving and maintaining the water quality of landscape water bodies in city parks,combined with experiments,and provided theoretical reference suggestions for improving the water quality of landscape water bodies in Guangzhou city parks from the aspects of water quality guarantee of replenishment,reasonable construction of submerged plants,matrix allocation of submerged plants,and management of landscape water bodies.The main research results are as follows:(1)Water quality status of landscape water in Guangzhou City Park: During the 4-month testing period,the water quality of Xiaogang Park was Class IV;The water quality of Dongshan Lake Park is Class V,NH4+-H has changed greatly,and TN concentration exceeded Class V in the November test.The water quality of haizhu lake Park is Class V,with great changes in various indexes during the month,of which TN concentration exceeded Class V in the November test.Of all the detected values in Xiangxue Park,only TN exceeded the Grade V water quality standard.During the testing period of White Cloud Lake Park,the water quality was Grade V;The monitoring results of Liuhua Lake Park are all worse than Grade V,with the exception of DO and p H,which are all beyond the standard of Grade V water quality.(2)Different water substrates have certain auxiliary effects on water purification.Simulation experiment of bitter herb water purification under different substrates: T1(control group): sediment+water+ Vallisneria natans,T2:sediment+two layers of non-woven fabric+sand+water+ Vallisneria natans,T3:sediment+two layers of non-woven fabric+corncob+sand+water+ Vallisneria natans,T4: sediment+two layers of non-woven fabric+activated carbon+sand+water+Vallisneria natans,T5: sediment+two layers of non-woven fabric+corncob+activated carbon+sand+water+ Vallisneria natans.According to the five physiological indexes of Sophora alopecuroides,adding organic substances into the matrix can promote the growth of plants,and the growth state of Sophora alopecuroides is the best in T3 and T5 test groups.Compared with the control group,the water purification effect of the four groups of tests is higher than that of the control group,and the T4 test group has the best water purification effect.In the last purification rate comparison,T5 has the fastest removal rate and the best purification effect.(3)Different submerged plants have different water purification effects under different configurations,and the water purification effects are quite different.Simulation experiments of submerged plant water purification under different configurations: T1(control group): bottom mud,T2: bottom mud+water+Vallisneria natans + Hydrilla verticillata + Ottelia alismoides,T3: bottom mud+water+ Ottelia alismoides + Hydrilla verticillata,T4: bottom mud+water+Vallisneria natans + Hydrilla verticillata,T5: bottom mud+water+ Vallisneria natans+ Ottelia alismoides.Among the four combinations,T4 has the best removal effect of chromaticity,NH4+-N and TN,with the removal rates of 91.18%,51.85% and48.11% respectively.T5 has the highest turbidity removal rate of 89.73%.T3 had the highest removal rate of TP,39.92%.According to the water purification effect of each test group and the water quality status,the most effective combination of water purificationis Kucao+Hydrilla verticillata+Glomerulosa,followed by Kucao+Hydrilla verticillata.(4)Suggestions for the improvement of landscape water quality in Guangzhou city parks: firstly,it is necessary to ensure the water quality of replenishment water.The incoming water and the collecting water of the 6 parks are all connected with the rivers in Guangzhou city.Therefore,submerged plants can be planted in the connected rivers to make them undergo plant purification treatment first.Secondly,it is necessary to construct a reasonable submerged plant ecosystem,that is,to construct a reasonable submerged plant ecosystem,that is,to carry out ecological management on the water environment and improve the landscape effect of the water environment.Furthermore,the matrix configuration in the water environment needsto be improved.Adding biomass coke to the matrix can accelerate the purification of the water body,but it also needs submerged plants to play a major role in maintaining good circulation of water quality.Finally,it is necessary to strengthen the management and maintenance of the landscape water body,mow the plants in time to prevent withered plants from entering the water,and timely salvage the garbage,dead branches and hay in the water to prevent the secondary pollution of the water body.