Leaf Functional Traits Of Oasis Plants And The Responses To Soil Moisture And Salinity In Extreme Arid Regions

Extremely arid oasis is a sensitive area of global change,especially water shortages and changes in hydrological processes had led to strong heterogeneity in the oasis soil environment.How plants adapt to high soil heterogeneity is a key scientific issue in the maintenance of oasis plant diversity.So investigating plant leaves,the most sensitive organ traits and their response to soil water and salt factors,is helpful to reveal the fundamental strategies of plant adaptation under environmental heterogeneity conditions.In this study,the common plant leaves of Ejina,a typical desert oasis,were selected as research objects,and eight leaf functional traits of 25 plants were selected,including leaf thickness(LT),leaf dry matter content(LDMC),specific leaf area(SLA),leaf carbon content(LCC),leaf nitrogen content(LNC),leaf phosphorus content(LPC),leaf carbon to nitrogen ratio(C/N)and leaf nitrogen to phosphorus ratio(N/P).The correlation between functional traits and their characteristics at the community level,life style,and dominant species were discussed,and the response of leaf functional traits to different soil water and salt environments was discussed.The results showed that:(1)At the community level,leaf functional traits adapted to extreme drought conditions through a certain degree of variation and a synergistic-balanced functional combination,and had a certain degree of difference in soil water and salt factors response,in which the salt content was under the environment.The effects of leaf functional traits were more critical.(2)At the life style level,the eigenvalues of most leaf functional traits were significantly different among different life styles,showing different nutrient utilization strategies,and different adjustment methods were adopted to adapt to the changes of water and salt factors.(3)At the level of dominant species,Sophora alopecuroides,Tamarix ramosissima and Populus euphratica were studied.Except for LCC and LDMC,the coefficient of variation of most leaf functional traits was large,and there were some differences in trait combinations,and the soil water and salt stress was resisted by adjusting different traits.In conclusion,studies at various scales had shown that the leaf functional traits of oasis plants adapted to extreme drought by forming a specific synergistic-balanced functional combination form,and responding to the stress of water and salt factors in the soil by adjusting functional traits.