Effects Of Different Restoration Measures On Saline-alkali Grassland Vegetation And Soil Characteristics

Inner Mongolia prairie is an important development base of animal husbandry in China,but in recent years due to the increasing frequency of human social activities,which leads to the decrease of grassland area and the increase of vegetation degradation.In particular,the salinization of grasslands in low-wetlands is becoming more and more serious in recent years,besides,its annual expansion rate is 2.00 ×105hm2,which has seriously affected the sustainable development of grassland animal husbandry in the pastoral areas in our country.With regard to that,from 2017 to 2019,the saline-alkali grasslands in the Zhalute Banner,located on the Tongliao city in Inner Mongolia,which were respectively repaired with the measures of sanding+rebroadcast,organic fertilizer+rebroadcast,desulfurized gypsum+rebroadcast,and humic acid+rebroadcast.By the research way of comparing,to study the effects of different restoration measures on vegetation characteristics of grassland plant,forage nutrient quality and soil physical and chemical properties,and discussed the effects of different restoration measures on the vegetation restoration of saline-alkali grasslands,which provides an effective,low-cost,and marketable restoration method for the restoration of Horqin saline-alkali grassland.The main research conclusions are as follows:(1)The community height,coverage,density and above-ground biomass of moderate and severe saline-alkali grasslands have been significantly improved after restoration.Among them,the above-ground biomass of the treasures of sanding+rebroadcast and organic fertilizer+rebroadcast respectively increased by 141.82%,35.75%,64.55%,and 97.38%;Saline-alkali soil plants decreased in the species composition of the community,and fine forages increased,all of which indicates that the restoration measures have a significantly positive impact on the saline grassland vegetation.(2)The four restoration measures significantly improved the dry matter,crude protein and relative feeding value of grassland forage(P<0.05).In particular,repair measure of sanding+rebroadcast has the best effect of increasing,The crude protein content of moderately and heavily salinized grasslands respectively reached 14.11%and 19.73%in the following year(2019)after restoration.In addition,the relative feeding value respectively reached 110.97 and 112.99.It can be seen that the remediation measures have better remediation effects on heavily saline-alkali grasslands.(3)Those various restoration measures all have significantly improved soil nutrients,physical properties,and salinity of saline-alkali grasslands.In addition,which increases the soil organic matter,available phosphorus,available potassium and other nutrients,and decreases the soil bulk density,pH,and alkalinity.In particular,the repair measure of organic fertilizer plus rebroadcast has the best effect.(4)Those various restoration measures all can promote the restoration of saline-alkali grassland ecosystem.The community characteristics,crude protein content and relative forage value of heavily saline-alkali grassland are higher than those of moderately saline-alkali grassland,The increase rate of soil organic matter in heavily saline-alkali grassland is higher than that in moderately saline-alkaline grassland.The general rule is that the recovery effect of severe salinization is greater than moderate salinization.(5)The treatment effect of sanding+rebroadcast is the best among other repair measures,the second is the repair measure of organic fertilizer+rebroadcast,so we can know that both of these two restoration measures can be used in the restoration of saline-alkali grasslands and other similar grasslands in Horqin area.