| In this paper,six kinds of tree species,include Liquidambar formosana Hance,were used as experimental materials to study the effects of water stress,then through rehydration,chlorophyll fluorescence,chlorophyll,tissue water content,relative conductivity And 5 categories of indicators as a means o f research,fuzzy membership function and coefficient of variation on the drought resistance of the tree were evaluated,the results show that:(1)Based on the net photosynthetic rate,transpiration rate,water use efficiency and stomatal conductance,the drought resistance ability of each tree species was as follows: Podocarpus nagi(Thunb.)>(Sischofia javanica Bl.)> Schefflera octophylla(Lour.)Harms)>Cassia siamea Lam.> Liquidambar formosana(Ormosia pinnata(Lour.)Merr.).O n the photosynthetic characteristics of indicators after the recovery of water from large to small: iron knife wood> Hainan red beans> autumn maple> duck feet wood> bamboo> Fengxiang.(2)The actual quantum yield Y(II)and relative electron transport rate(ETR)of chlorophyll fluorescence index(PSI)were positively correlated with the physiological growth of plant,while non-regulated energy dissipation Y(NO)and non-photochemical quenching coefficient NPQ Physiological growth was negatively correlated.Based on the chlorophyll fluorescence characteristics of the comprehensive tree species,the comprehensive evaluation of chlorophyll fluorescence index of different tree species can be obtained.The drought resistance ability is as follows: bamboo grass> autumn maple> Liquidambar formosana>The recovery ability of different tree species was significantly different,and the recovery ability was as follows: duck foot wood> Hainan red bean> sweet orange> iron knife wood> autumn maple> bamboo.(3)Chlorophyll a and chlorophyll b were negatively correlated with the degree of drought.The chlorophyll a,chlorophyll b,the trend of drought resistance,the ranking of drought resistance is as follows: bamboo> Hainan red beans> autumn maple> duck foot wood> iron knife wood> Liquidambar formosana.After the resumption of its ability to restore the rankings are as follows: Liquidambar formosana> Dendrobium> Ducks feet> Hainan red beans> bamboo> autumn maple.(4)The relative water content of leaves of different tree species showed a decreasing trend under drought stress,and continued to rise after rewatering.The relative water content of leaves was negatively correlated with drought degree.On the relative changes in water content can be derived from the drought resistance rankings are as follows: duck feet> Hainan red beans> bamboo> autumn> maple> iron knife wood.After the resumption of water after the recovery of the rankings are as follows: iron knife wood> sweet potatoes> autumn maple> bamboo> duck feet> Hainan red beans.(5)Under the drought stress,the relative conductivity of the leaves increased gradually,and then decreased gradually after rehydration,and the relative conductivity of the leaves was positively correlated with the degree of drought.O n the relative conductivity of the blade of this indicator,the drought resistance ranking: Liquidambar formosana> Hainan red beans> iron knife wood> autumn maple> duck feet wood> bamboo.In the recovery capacity after rehydration ranked: bamboo> Hainan red beans> autumn maple> iron knife wood> duck feet wood> Liquidambar formosana.(6)Through the fuzzy membership function and the coefficient of variation,the different indexes of different tree species were sorted and sorted,and the drought resistance of different tree species was evaluated comprehensively.The drought resistance of different tree species could be obtained from: > Duck feet wood> iron knife wood> Liquidambar formosana.(7)Based on fuzzy membership function and coefficient of variation,the different indexes of different tree species were sorted and sorted,and the recovery ability of different tree species was evaluated comprehensively.The recoverability of different tree species could be obtained from: Iron knife> bamboo> autumn maple> Liquidambar formosana. |
