Study On Several Halophytes For Improvement Of Secondary Salinization In Soils

China's facility horticulture has developed rapidly and its area ranks first in the world.Facilities gardening has become an important production method for increasing agricultural output and increasing farmers'income.However,the unreasonable use of fertilizers and the backwardness of management have led to the occurrence of secondary salinization of soil,resulting in a decline in crop yields and deterioration in quality.Crops in some facilities are no longer able to grow normally and even threaten the safety of the surrounding environment.Therefore,it is imperative to improve secondary soil salinization in facilities.At present,there have been many advances in the use of halophytes to improve the saline-alkali soil,but research has focused on natural saline-alkaline lands.In this study,the secondary soil salinized greenhouse soil in Maanshan City was investigated and tested,and Ca?NO3?2 that caused secondary salinization was used for the short-term and the three salt plants of Salicornia europaea,Suaeda salsa and Mesembryanthemum crystallinum.Long-term stress test study,the results are as follows:1.The pH of the soil in the greenhouse decreased by about 0.93 units compared to the adjacent open land,and the soil acidification occurred.Ca²⁺and NO₃^-are the main salt segregants that cause secondary salinization of greenhouse soil in He County.2.Treatment with 80 mg/L Ca?NO3?2 inhibited the accumulation of dry and fresh weight of the Mesembryanthemum crystallinum,had no significant effect on the growth of Salicornia europaea And promote the growth of Suaeda salsa.3.Most of the ion concentrations in Salicornia europaea,Suaeda salsa and Mesembryanthemum crystallinum were highest in the early period of fertility,and then decreased with the advancement of fertility.The concentration of Na+,Cl-,and SO42-in three kinds of halophytes is very high,which is significantly different from other ions and is the main part of salt in vivo.