Study On The Effect Of New Submerged Planting Method

At present,there are three methods of planting submerged plants: cutting method,sinking method,and seeding method.Planting submerged plants using sink method.are convenient,but the survival rate is not as good as that of cutting method.In order to improve the survival rate of sinking cultivation,the experiment in this article attempts to use agar as the cultivation substrate for sinking cultivation.The agar is dissolved in hot water,and the agar is cooled to about 30 °C.At this time,the agar is in a solid and liquid mixed state and submerged plants are planted in it.The experiment explored the differences on the physiological characteristics of submerged plants and the changes in water quality,under different conditions of different agar concentrations,different agar planting depths,and agar doped with other substances(including coconut palm,molecular substances,etc.).In the test,the agar matrix will be mixed with small stones,so that the matrix can be fixed to the bottom of the water well.First,this article tested the influence of four kinds of planting matrix,including soil,agar,coconut fiber,and bentonite mixed in agar,on the planting of bitter grass,that is,inserting bitter grass into the soil,agar(the soil is at the bottom),and the mixture of coconut fiber and agar(the soil is at the bottom),the mixture of bentonite and agar(the soil is in the bottom layer),and the external environment such as water quality and light were controlled.The test results show that except for bentonite mixed with the agar group,the other groups of bitter grass can grow and reproduce very well.Analysis shows that there may be harmful trace elements in the bentonite,which inhibits the development of bitter grass.In addition,the water quality of each group of water can be purified to varying degrees.The above shows that it is feasible to use agar instead of soil for sink cultivation.Secondly,the experiments in this article compared the difference of five matrix on submerged plant cultivation,including A5(agar concentration 5 mg / L),A10(agar concentration 10 mg / L),A15(agar concentration 15 mg / L),A20(agar concentration20 mg / L),and S.The strength of different concentrations of agar itself is different,and the growth of H.verticillata and the water quality of the aquatic plants are also different.The test results showed that the H.verticillata of A10 and A20 groups grew better,but the water quality of these two groups was not the best.The purification of water quality was also closely related to the microorganisms attached to the plants.Thirdly,the differences in planting depth were compared in this experiment,including 0(direct planting in the soil),1(plants were planted in agar,the physiological bottom of the plant was 1 cm from the soil surface,and the following figures follow the reference),4 and 5,Each group showed obvious physiological differences.The comprehensive comparison of the two plant physiological indicators of fresh weight and average plant height showed that V.natans of the 4 groups performed more prominently,while the H.verticillata group had the highest average fresh weight of the 4 groups and the highest average plant height of the 2 groups.Different planting depths have a certain effect on plant growth,and appropriate planting depths can have positive effects on the development of V.natans and black algae.Then,the experiments in this article compare A(only agar,no soil at the bottom),C(only coconut palm,no soil at the bottom),AC(only agar-coco palm mixed substrate,no soil at the bottom),and AS(plants planted in agar,bottom)With soil),ACS(plants planted in coconut palm agar,soil at the bottom),S(soil only)on physiological performance of submerged plants and water quality.In the Ceratophyllum demersrm L.group,the growth performance of the A group was the worst,the ACS group performed the best,and the water quality was also the better performance of the ACS group;in the H.verticillata test group,the C group had the worst growth performance,and the ACS group had the best growth performance.The degree of water purification in the ACS group was also higher.The analysis suggests that the incorporation of coconut fiber increases the permeability of the matrix body.After the root system penetrates the agar layer,the soil layer can continue to provide sufficient nutrients for the plant.The stimulation of the barren matrix and the nutrient supplement after breaking through the agar layer make the plant better growth and reproduction.Finally,this article compares different strength enhancers incorporated into agar,including potassium chloride(0.2%,14.7% increase in shear strength),locust bean gum(4%,16% increase in shear strength),and gelatin(3%,Shear strength increased by13.6%),the concentration of raw material agar is 10 g/L,and its shear strength is about0.02 MPa.The experimental comparison found that the growth of the 2 groups in the V.natans group was better,and the growth of the other groups was similar;the growth of the 2 groups in the H.verticillata group was the worst,and the other groups were similar.According to the analysis,0.2% potassium chloride can supplement the nutrients required for the growth of V.natans,while it can inhibit the H.verticillata,and the growth of the other groups of plants is similar.Not only can incorporating suitable substances into agar enhance the shear strength of the matrix,but also it can promote the growth of plants.