Study On The Fertility Betterment Improvement Effect Of Willow On Seashore Saline Soil

Because of poor physical and chemical properties, for instance，more salt、high pH、badstructure、innutirtion, seashore saline soil has a great inlfuence on plant growth and soil use.Therefore, as a back-up of the useful land resources, how to make the improvement andutilization of seashore saline soil is an important signiifcance to alleviate the shortage of landresources and improve ecological environment. Bamboo willow as the Salicaceae Salix plants,mostly has a strong salt tolerance. By willow seedlings or planting tiral in typical seashore salinesoil, to research the willow how to make an influence on physical properties、chemical propetriesand biological properties of seashore saline soil. Through combination of soil fertility evaluation,to analyze the effects of seashore saline soil fertility by planting willows on the seashore，toprovide a basis for seashore saline soil use and plant improvement. The main results are asfollows:1.Cutting willow seedlings and creating willow plantations in seashore saline soil canimprove soil physical properties. In0?20cm、20-40cm soil, the bulk density of seedling land andforest land are markedly decreased by6.53%、10.99%and13.92%、10.00%compared with CKin late autumn respectively, in early summer the soil bulk density is decreased by14.50%、17.24%and14.93%、17.02%. In late autumn, the maximum moisture capacity of seedlings landin0²0cm、20?40cm、40?60cm soil increases10.31%、11.06%、10.79%respectively comparedwith CK，the capillary capacity and ifeld capacity increase11.28%、13.19%、7.31%and7.51%、5.91%、4.91%，the increasing extent is less than that in early summer; forest land is slightlyhigher than seedlings land, and the variation characteristics is basically the same. In upper layersoil，capillary porosity and total porosity of seedlings land respectively are over CK6.58%、3.14%in late autumn markedly, forest land which are10.34%，10.24%，trend is the same withearly summer.2.Seedlings and afforestation improve chemical properties of seashore saline soil and theeffect in upper layer is better than the lower one. Soil pH of Seedlings land and forest land in lateautumn in0?20cm soil respectively is decreased by3.21%、6.70%that than CK signiifcantly, and3"₁.69%、5.24%in early summer. Total salt content is respectively3.33g.kg\2.67g.kg in earlysummer which is signiifcantly decreased by79.19%、87.50%than CK, the trend in late autumnand early summer is basically same, but change amplitude is slightly less than early summer. Thesoil organic matter content of seedlings land in late autumn and early summer in three layerrespectively are over CK39%、51%、50%and51%、57%、53%signiifcantly. Increased amplitudeof forest land is slightly smaller than that of the seedlings land. In addiiton，the two kinds ofupper layer nitrogen content in late autumn signiifcantly increases1.33times>2.63times than CK,the content of available phosphorus increases0.69times、1.12times，trend in the early summer is basically same.3.Seedlings and afforestation have a signiifcant impact on the quantity of soil microbial、microbial biomass carbon and enzyme activities, and the effect of upper layer is greater than thelower. In late autumn, the quantity of bacteira、actinomycetes and fungi in0?20cm soilsigniifcantly increase l.lOtimes、8.35times and0.54times on seedlings land and1.26times、8.20times、0.55times on forest land compared with CK. Microbial biomass carbon increases0.30times and0.42times in seedlings land and forest land，and activity of phosphoatase、sucrose、urease and catalase increase2.04times、0.59times、0.41times、0.31times and4.77times、0.78times、0.51times、0.31times. In20?40cm soil，the quantity of microbial increases0.69times、2.41times、0.86times on seedlings land and0.71times、2.35times、0.90times on forest landcompared with CK. Microbial biomass carbon increases0.17times and0.27times on seedlingsland and forest land. Enzyme activity increases0.29times>0.51times、0.63times、0.43times and0.88times、0.14times、l.OOtimes、0.39times. In early summer it changes basically the same as thelate autumn, and the change amplitude is greater than the late autumn.4.Through the evaluation of soil index, the index of integrated soil fertility are as follows:forest land（late autumn）> forest land（early summer）> seedling land（early summer）> seedlingland（late autumn）> CK（autumn）> CK（early summer）, therefore, afforestation makes largerimprovement on seashore saline soil fertility, it is because of the influence of the forest with largetree crown, well-developed roots and much litter.Thus, a certain extent，cutting willow seedlingsand afforestation in the seashore saline can improve soil properties and soil fertility.