Comparison Of Drought Resistance Of Eight Color Tree Species In Beijing Shallow Mountain Areas

Shallow mountain area is the interlaced area between mountainous areas and plains.In recent years,due to its unique geographical advantages,it attracts many tourists,but at the same time there are problems such as small seasonal changes and poor landscape effects.Based on the climatic characteristics and environmental characteristics of shallow mountain areas in Beijing,the paper selects Toona sinensis Roem.,Amygdalus davidiana(Carriere),Pistacia chinensis Bunge,Acer trancatum Bunge and Cotinus coggygria Scop,Koelreuteria paniculata Laxm.,Syringa amurensis Rupr.and Acer negundo Linn..We researched the physiological and biochemical characteristics of plants and their response to drought stress by indoor pot planting simulations experiments.Aiming to provide technical support for the selection of ornamental trees in shallow mountain areas in Beijing.The results of the study are as follows:Indoor drought stress experiment:The soil water content was 60%,40%and 20%of the field water capacity,respectively.By determining the physiological indicators of chlorophyll,catalase,peroxidase,superoxide dismutase,malonaldehyde,soluble protein,nitrogen concentration,phosphorus concentration,and potassium concentration,it is preliminarily concluded that all the trees have different responses to drought stress.Under severe drought stress,the highest POD but CAT activities and the lowest POD activity were detected in Syringa amurensis Rupr..It shows that the lilac in the protective enzyme system mainly relies on POD and CAT to scavenge free radicals,smaller the damage of the membrane.In different drought stress,Acer trancatum Bunge had higher soluble protein content,indicating that Acer had better osmotic regulation ability.From the aspects of plant adaptability to drought and drought productivity,the membership function method was used to comprehensively evaluate the drought resistance of various tree species in the indoor pot simulation experiment.It is concluded that the drought resistance of the eight tree species was Acer trancatum Bunge>Acer negundo Linn.>Koelreuteria paniculata Laxm.>Cotinus coggygria Scop>Pistacia chinensis Bunge>Amygdalus davidiana(Carriere)>Syringa amurensis Rupr.>Toona sinensis Roem.under mild drought stress.Under moderate drought stress,the drought resistance of Eucalyptus was ranked first,and the drought resistance of eight tree species was Koelreuteria paniculata>Cotinus coggygria Scop>Acer trancatum Bunge>Toona sinensis Roem.>Syringa amurensis Rupr.>Acer negundo Linn.>Amygdalus davidiana(Carriere)>Pistacia chinensis Bunge.In severe under drought stress,the drought resistance of various tree species changed again:Acer trancatum Bunge>Acer negundo Linn.>Koelreuteria paniculata Laxm.>Cotinus coggygria Scop>Syringa amurensis Rupr.>Toona sinensis Roem.>Pistacia chinensis Bunge>Amygdalus davidiana(Carriere).According to the adaptability of each tree species to drought and the productivity of drought resistance in the three stress stages,we finally determined that the drought resistance of the eight tree species in the pot simulation experiment was Acer trancatum Bunge>Koelreuteria paniculata Laxm.>Acer negundo Linn.>Cotinus coggygria Scop>Syringa amurensis Rupr.>Toona sinensis Roem.>Pistacia chinensis Bunge>Amygdalus davidiana(Carriere).