Soil Material Deposition And Enrichment Characteristics Of Three Clustered Plants In Degraded Desert Grassland

Stipa breviflora,Oxytropis aciphylla Ledeb and Cynanchum komarovii Al.Iljinski are three common plants in degraded grassland of desert steppe,and can stably exist and maintain their grazing disturbance.The relative advantage of the population.These three types of clumps constitute the skeleton of such grassland communities,and are also the vegetation base for the relatively stable grassland under the disturbance of grazing.Soil is the basic factor determining the distribution pattern of plants.At the same time,plants also affect the distribution of soil.There is obvious mutual interaction between them.Shallow soil is the concentrated area and key area of interaction between plants and soil processes.The spatial distribution patterns of shallow soil sedimentation and enrichment in three small scales(inside and outside the plant)were studied,which contributed to the deep understanding of the stability mechanism of degraded grassland in desert steppe.In this study,the free grazing grassland was used as the object,and the fenced grassland was used as the control.The grain components of the three species of the plant,Stipa breviflora,cat head thorn,and old melon head(0-14 cm),were compared.).organic carbon(SOC)and total nitrogen(TN)deposition and enrichment distribution pattern.The main findings and conclusions are as follows:In terms of the whole soil layer,the encapsulation increased the soil clays of Stipa breviflora and Oxytropis aciphylla Ledeb by 16.69%and 46.33%,respectively,and the sand grains decreased significantly by 13.40%and 36.99%.and the particles decreased significantly by 3.50%and 9.34%.The SOC of P.stipitis was significantly increased by 0.57%(P<0.05),and the SOC was synchronous with the change of cosmid.The encapsulation did not significantly change the overall distribution pattern of soil particle composition,SOC and TN in the old melon head cluster(P>0.05).The grazing disturbance only significantly increased the enrichment rate "E" of the old melon head TN(P<0.05).2 cm fine stratification of soil material deposition,(1)The increase of mucilage in the enclosed area of Stipa breviflora,In the grazing area,the soil layer of 0-12cm is stable,the content of 12-14cm soil layer is significantly increased,and the sand envelope area decreases,and the grazing area increases and decreases,SOC 0-2cm soil surface polymorphism is prominent in the grazing area,and the presence of planting plexus under this condition is beneficial to increase the content of TN intermediate soil layer in planting plexus.(2)The change of soil layer did not affect the Oxytropis aciphylla Ledeb distribution of SOC and TN;As the soil layer deepens,the depth of change of particle composition in the surrounding area is 0-6cm.and the grazing area is below 8cm,especially outside the vegetation;SOC-table aggregation is prominent,and TN is prominent under grazing interference.(3)Enclosure significantly changed the distribution of soil clay and silt content in Lower Cynanchum komarovii Al.Iljinski soil layer,the clay content decreased significantly and the silt content increased significantly(P<0.05),and had no significant effect on soil sand,SOC and TN(P>0.05);with the deepening of the soil layer,the clay content increased continuously with the deepening of the soil layer,and the silt and sand showed a trend of continuous gradual decrease,and relative.The trend of change in fencing area is small.Soil material enrichment under 2 cm fine stratification,(1)The presence of vegetation under enclosure did not inhibit soil degradation,but was beneficial to the increase of soil sand content in 2-12 cm soil layer.Fence enclosure did promote the phenotypic enrichment of SOC in Stipa breviflora bushes,while soil depth had no significant effect on SOC enrichment under grazing disturbance(P>0.05);and TN had no significant effect on SOC enrichment under enclosure conditions(P>0.05).Under grazing disturbance,the "E" value of 4-8 soil layer decreased significantly(P<0.05).(2)The Oxytropis aciphylla Ledeb vegetation in enclosed area had no significant effect on the enrichment of soil mechanical composition(P>0.05);on the contrary,under grazing disturbance,soil clay fraction decreased with the deepening of soil layer.The existence of vegetation clumps did play an effective role in enriching SOC content.Under the two grassland utilization modes,the change trend of soil layer change on "E" value was obviously different especially under 8 cm soil layer,the enclosed area increased first and then decreased,while the grazing area had the opposite change trend.(3)In enclosed area,the "E" values of mechanical composition of soil in individual soil layers were different,but they did not reach a significant level(P>0.05);on the contrary,the presence of vegetation in grazing area was beneficial to the enrichment of fine particulate matter in surface soil of Cynanchum komarovii Al.Iljinski vegetation.The relative enrichment of SOC enclosed area was stronger than that of grazing area,but it did not reach a significant level(P>0.05).Under grazing disturbance,the "E" value of TN enrichment increased first and then decreased,and the "E" value of 4-6 cm soil layer was the largest.Summarize the above research results and get the following conclusions:The effects of the three plants on the soil were significantly different under the two methods of enclosing and grazing.Grazing and enclosing had no significant effect on the distribution of granules in the old melon head,but significantly affected the distribution of soil granules in the cat thorn and Stipa breviflora,especially in the Oxytropis aciphylla Ledeb cluster.The value is about 40%.The increased SOC of the cosmids also increased simultaneously,but had no significant effect on TN.Plant clusters have significant species differences in SOC and TN enrichment.