Leaf Reflectance Spectra And Seed Germination Of Two Species Of Polygonaceae In Different Polluted Areas Of Jinchang

There are many sources of heavy metals in the soil,such as mining,electroplating and other industrial discharge,sewage irrigation,agricultural chemical use,gas deposition,etc.Heavy metals are highly toxic,easy to accumulate in the soil,affecting soil quality,and then transferred to plants.The growth and development of plants is transferred to animals or humans through the food chain,endangering human health.The growth and development status of plants can be used as an indicator of whether the ecosystem is polluted.When the plants are poisoned by heavy metals,they will inhibit the activity of the enzymes,hinder the synthesis of chlorophyll,and cause the leaves to appear green,while the changes in the pigment content of the leaves of the plants,It will cause a change in its spectral characteristics,the spectral reflectance of the visible and near-infrared portions will increase or decrease,and the red edge inflection point will appear “red shift” or “blue shift”.In general,the more severe a plant is contaminated,the greater the spectral characteristics change.Therefore,it is necessary to study the relationship of heavy metals in plant-soil.Cuprum is a micronutrient element essential for plant growth and development,and plays an important role in protein synthesis,photosynthesis,respiration and plant metabolism.Excessive copper content will affect the normal metabolic function of plants,and will cause harm to the nutrient absorption,growth,yield and quality of plants.Nickel is one of the essential micronutrients in certain lower organisms and plants,and is also a carcinogenic toxic element.Excessive nickel in the soil can retard plant growth and development.When the accumulation of nickel in the human body reaches a certain level,it will become viral.In this paper,we studied the variation of the spectral curves of two herbaceous plants,Salsola collina and Halogeton glomeratus,in three different heavy metal contaminated areas in Jinchang,and the heavy metal content and plant heavy metals in the rhizosphere soil.The relationship between content and chlorophyll content and reflectance spectral parameters was established,and a linear regression model was established.Sensitive parameters were selected and the heavy metal elements in the leaves were inverted by these sensitive parameters.The purpose is to reveal therelationship between heavy metals and plant photosynthetic efficiency;Effects of seedling heavy metals on growth and physiology of Salsola collina and Halogeton glomeratus seedlings by indoor seed germination experiment.The results show:(1)The effects of heavy metals Ni and Cu on the germination of Salsola collina and Halogeton glomeratus seeds were similar.The concentration of heavy metals was too high to inhibit germination.When the concentration of Cu solution was 200 mg/L and the concentration of Ni solution was 250 mg/L,the seeds were seeded.The damage was severe and the difference was significant compared to the control.(2)The effects of two heavy metals on the physiological indexes of the seedlings of Salsola collina and Halogeton glomeratus were also similar.When the seedlings of Salsola collina and Halogeton glomeratus are subjected to heavy metal stress,SOD,proline and soluble sugar can remove excess reactive oxygen species in the body to a certain extent,regulate the osmotic potential,and have the ability to endure heavy metals;when the concentration of Cu solution is 200 mg/L and Ni solution was 250mg/L,the accumulation of MDA increased,which was significantly different from the control,and the normal growth of the seedlings was inhibited.(3)Chlorophyll has an indication effect on soil and the pollution of Ni and Cu in Salsola collina and Halogeton glomeratus.(4)It can be used to monitor Ni and Cu pollutionin the soil of Salsola collina by establishing a ground spectrum model of Ni and Cu content in soil and red edge position,red edge amplitude,red valley position,blue edge position and green peak position;by establishing the ground spectrum model of Ni and Cu content in the soil and the location of the red valley of the Halogeton glomeratus and the Normalized Pigment Chlorophyll Index NPCI,it can be used to monitor the Ni and Cu pollution in the soil of the Halogeton glomeratus.(5)Red Valley location can be used as a spectral indicator for the growth of the herbaceous plants of Nitrogen under the pollution of Ni and Cu.It has a good indication for the growth of the herbaceous plants and the pollution of Ni and Cu under the pollution of Ni and Cu.