Relationship Between Soil Chemical Properties And Typical Plant Species Under Forests Of Platycladus Orientalis And Pinus Tabuliformis In Beijing Mountainous Area

This study takes the second phase of forestry project in sandification combating program for areas in the vicinity of Beijing and Tianjin from 2013 to 2018 as the research object,and selects 196 sample plots for investigating and analyzing.According to the slope exposure and main afforestation tree species,these plots can be divided into four categories for a standard investigation: forest of Platycladus orientalis on sunny and shady slope,and forest of Pinus tabuliformis on sunny and shady slope.The typical shrub and grass species under the forest were identified.The relationship between soil chemical properties(soil organic matter,p H,total nitrogen,total phosphorus,total potassium,available nitrogen,available phosphorus,available potassium)and plant species was analyzed via SPSS,while suitable models for representative plants and simulating their distribution were constructing via Max Ent Model.The results show that:(1)The correlation between soil chemical properties and plant species under forest was significant,and there are large differences between different species.(2)We established the suitability model of Grewia biloba under forest of Platycladus orientalis on sunny slope.The contents of available phosphorus and organic matter in soil contributed most to its distribution.When the content of available phosphorus is less than4.5mg/kg,and the content of soil organic matter is within13~62g/kg,the suitability index is over0.5,while the suitable area accounting for54.9%of the total area of that forest.(3)The contents of available phosphorus and organic matter in soil contributed most to distribution of Selaginella sinensis under forest of Platycladus orientalis on shady slope.When the content of available phosphorus is less than5.2mg/kg,and the content of soil organic matter is more than 14g/kg,the suitability index is over0.5,while the suitable area accounting for58.4%of the total area of that forest.(4)The contents of total phosphorus and available phosphorus in soil contributed most to distribution of Dendranthema chanetii under forest of Pinus tabuliformis on sunny slope.When the content of total phosphorus is less than 0.5 g/kg,and the content of available phosphorus is less than 4.3 mg/kg,the suitability index is over 0.5,while the suitable area accounting for 44.1% of the total area of that forest.(5)The contents of total phosphorus and available potassium in soil contributed most to distribution of Spiraea trilobata under forest of Pinus tabuliformis on shady slope.When the content of total phosphorus is less than 0.5 g/kg,and the content of available potassium is less than 125 mg/kg,the suitability index is over 0.5,while the suitable area accounting for 67.3% of the total area of that forest.