Study On The Desalination Effect Of Suaeda Salsa On Saline-alkali Soil

Object : Suaeda salsa is a pioneer repair plant for biological improvement in Xinjiang.Suaeda salsa is planted on salt wasteland.The desalination effect and desalination period of salt wasteland are discussed,which has important promotion value for agricultural development and habitat restoration in Xinjiang.Methods : Through the initial cultivation experiment of Suaeda salsa in saline wasteland,three salinity levels of bucket cultivation experiment were determined as 1.0%,1.5%,2% and 146 groups of mild saline-alkali soil as the control group,which were denoted as S0,S1,S2 and CK;monitoring water and salt,dry matter,plant growth dynamics.The study revealed the variation law of plant growth dynamics,water-salt migration and desalination effect of Suaeda salsa in saline land,and compared and combined them according to the field experiment and bucket cultivation experiment.A scientific and efficient field planting strategy of Suaeda salsa was proposed.Conclusion:(1)The initial planting of salt wasteland had obvious changes in soil moisture,the surface soil moisture content was 6.23%-11.16%,and the water content increased first and then stabilized with depth.The moisture content of deep soil remained at 11%-15% alternating change.At the beginning of the growth period,the soil moisture content changes between 5% and 12%,and at the end of the growth period,the soil moisture content changes between 12% and 17%.Continuing planting field 0-20 cm soil moisture content changes significantly in 8.65%-13.78%,deep soil moisture content in addition to March mostly maintained at 8%-21%,20-150 cm soil moisture content in 14%-19% alternate change.Soil moisture content varied from 5% to 13% in March.(2)The salt content in the surface layer to the root zone of the initial planting soil gradually increased with depth,and then decreased to 100 cm,and then the salt content in each soil layer tended to be stable between 10 g/kg and 12 g/kg.The salinity in the surface layer was small;the minimum was 8.82 g/kg.The salt content of40-60 cm soil layer is the largest,the maximum is13.36g/kg.100-150 cm soil salinity stabilized at 9g/kg-12g/kg;the average desalination rate in 2021 was 31.19%;the average desalination rate in 2020 was 17.61%,and the average desalination rate in two years for Suaeda salsa planting was 24.40%.(3)The dry matter content of Suaeda salsa in the field was significantly changed,and increased with the growth period,and the dry matter content of aboveground part was proportional to that of underground part.The plant height and stem diameter of Suaeda salsa increased with the growth period.The maximum plant height and stem diameter were 83.36 cm,1.44 cm and 89.88 cm,1.56 cm in October in 2020 and2021,respectively.In 2020 and 2021,the aboveground biomass,ash and ash salt were 15494.89 kg/hm2,22.32%,4277.64 kg/hm2 and 17207.33 kg/hm2,24.45%,4616.41 kg/hm2,respectively.(4)The changes of water content and salt content under different treatments in bucket planting experiment were S2>S1>S0>CK,and the lowest salt content of water content in May was higher.At the last sampling in October,the salt content of each soil layer was small,and the highest salt content of 30 cm was up to 20.40 g/kg under different treatments.The change of CK salt content in bucket planting experiment was relatively gentle and finally stabilized at 1 g/kg-2 g/kg.(5)The growth changes of Suaeda salsa plants under the same treatment were significant,and the changes in different periods under different treatments were S1 > S0 > S2 > CK.The maxi mum dry matter mass and plant height of Suaeda salsa under S1 treatment were 46.45 g and 90.83 cm,respectively,which were 2.07 and 1.21 times higher than those under CK treatment,respecti vely.The growth cumulative percentage of Suaeda salsa increased more than 18.44% in August,S eptember and October.(6)The combination and verification of bucket planting test and field test showed that Suaeda salsa should be planted continuously for 4 years in salt wasteland to reach the suitable salinity range of economic crops.Therefore,Suaeda salsa can be cultivated in salt wasteland for four consecutive years.On the one hand,it can export salt in irrigation area.On the other hand,it can be used as vegetable development in adult plant stage of Suaeda salsa,and corn combined with Suaeda salsa can be used as livestock silage in early flowering stage.