Effects Of Simulated CO₂ Concentration Increase And Precipitation Change On The Physiological And Ecological

The increase of CO₂ concentration caused by greenhouse gas emissions and the change of precipitation pattern caused by it,the frequent occurrence of extreme precipitation events seriously restricts a series of physiological and ecological processes of plants.In recent years,the climate in southwestern China has shown a trend of warming and drying.The frequent occurrence of drought caused by the increase of CO₂ concentration has had a more severe impact on plant physiology and ecology.In this study,the medicinal and food homogenous plant M.which is widely distributed in China,was used as the research object.The CO₂ artificial climate box control test method was used to simulate 4 precipitation gradients?0%,-30%,-55%,-75%?and 2 CO₂concentration gradients?400±10ppm,750±10ppm?and their synergistic effects on the physiological and ecological characteristics of Mentha haplocalyx Briq,through the adjustment of it growth,photosynthesis,relative water content,nutrient content,osmotic adjustment.The measurement and analysis of a series of parameters of substances,antioxidant systems,secondary metabolites and volatile oil provide a scientific theoretical basis for predicting the physiological and ecological adaptability of M.to future environmental changes.The main findings are as follows:?1?The increase of CO₂ concentration mainly promotes the growth of plant height in the precipitation,and comprehensively promote the growth of M.?2?The increase of CO₂concentration mainly adjusts the chlorophyll fluorescence fluorescence parameters of mint is enhanced.?3?The increase of CO₂concentration eases the decrease of the relative water content of M.promoted.Prevent water loss caused by reduced precipitation.?4?Elevated CO₂ concentration promotes the accumulation of nitrogen,phosphorus,and increased CO₂ concentration and reduced precipitation.?5?Increased CO₂ concentration and changes in precipitation Osmotic adjustment by precipitation,releasing SOD and POD enzymes Actively scavenges free radicals.?6?The increase of CO₂concentration is conducive to accumulating the content of menthol content approaches zero...