Analysis Of The Relationship Between Vegetation Coverage And Soil Nutrients In The Frozen Soil Region Of The Greater Xing'an Mountains

In order to study the relationship between vegetation cover and soil nutrients in the permafrost region of the Greater Xing'an Mountains,this paper focuses on the change of soil environment,and takes the frozen soil area passed by the Sino-Russian crude oil pipeline as the research area,and uses the two remote sensing images of 2014 and 2019 as the basis Data,combined with the actual collection of soil samples for monitoring data,and the use of GIS technology to analyze the relationship between vegetation coverage and soil nutrients,and study the changes in soil nutrients under different vegetation coverage in permafrost regions,with a view to evaluating and predicting for many years Permafrost ecosystems provide scientific basis for their stable structure and function under the global climate change environment.The main conclusions are as follows:(1)Based on the Landsat remote sensing data of the study area in 2014 and 2019,using ENVI5.3 to extract the vegetation coverage information of the study area,it was concluded that the average vegetation coverage of the study area decreased from 84.03%in 2014 to 72.10%in 2019.This phenomenon may be caused by the combined effect of human development activities and permafrost vegetation on natural factors such as climate change and permafrost melting.(2)At altitude,the content of organic matter is the largest in the range of 400?500m;the maximum value of pH is in the range of 0?300m;the maximum content of total nitrogen is 400?500m;On the slope,the highest pH value is on a steep slope(5.51);the highest value of organic matter content is 81.42g/kg on a flat slope,and the minimum value is 37.53g/kg on a steep slope;The value is also located on a gentle slope at 6.12g/kg.The maximum total phosphorus content is 1.28g/kg.(3)There are 6 communities in the study area,including 74 species and 65 genera.The ranking relationship of the Simpson index is high,medium high,low,medium,and extremely low.The Shannon-Wiener index and biomass differed significantly on different coverage quadrats.(4)The pH range of soil nutrients in the study area is 5.17?6.21,the organic matter content is 12.95?216.12g/kg,the total nitrogen content is 0.51?8.57g/kg,and the total phosphorus content is 0.23?1.85g/kg.The soil in the soil area is weakly acidic and the soil fertility is very high.There is a significant negative correlation between soil pH and vegetation coverage,that is,pH decreases with increasing vegetation coverage.Except for medium and high vegetation coverage,the organic matter content was significantly different at all levels,and all showed a positive correlation.Except for the middle vegetation coverage,the total nitrogen content has significant differences in other grades,and is positively related to the vegetation coverage.The total phosphorus content was significantly different under very low,medium,high,and high vegetation coverage,and the difference was small at other levels.(5)From 2014 to 2019,the average organic matter content in the high vegetation coverage area increased by 43.96%,the medium and high vegetation coverage area increased by 17.91%,and the medium coverage increased by 21.11%.Low and very low coverage decreases.Soil total nitrogen content increased by 20.18%,46.79%,and 48.18%in high,middle-high,and medium-coverage areas,and decreased by 3.12%and 37.08%in low and very low coverage.Soil total phosphorus content increased by 6.75%in high vegetation coverage areas,and increased by 28.57%,18.13%,and 5.89%in medium-high,medium,low,and extremely low vegetation coverage,respectively.The change in pH from 2014 to 2019 is mainly reflected in the decrease in high,medium high and very low vegetation coverage areas,and the increase in medium and low vegetation coverage areas.