Analysis Of Factors Affecting Spatial Distribution Of Soil Phosphorus In Gutian Mountain National Nature Reserve

Phosphorus is the necessary nutrient element for plant growth.The overall level of phosphorus in China is low and the spatial and temporal distribution is different.In this paper,24 ha evergreen broad-leaved forest in Gutian Mountain National Nature Reserve was used as the research object to analyze the factors affecting the spatial distribution of phosphorus nutrients in the study area.To understand the soil fertility of evergreen broad-leaved forest and to cope with the mechanism of phosphorus deficiency,it provides theoretical support for the protection of evergreen broad-leaved forest and plantation management in subtropical regions of China.The soil samples of 893 samples in the plot were collected according to the specific situation of Gutian Mountain,and the soil physical and chemical properties of soil total phosphorus,available phosphorus and available phosphorus were analyzed.And the autocorrelation of soil phosphorus in soil samples was examined.The soil phosphorus elements obtained from the actual investigation were subjected to Ordinary Kriging and then re-sampled to four spatial scales:10×10m,20×20m,40×40m,50×50m these four spatial scales.The woody plants with DBH greater than or equal to 1 cm were collected as their community data.The topographic factors such as elevation,slope,aspect and convex and concave are measured,and the spatial factor is expressed by the neighborhood coordinate matrix.Finally,the variation partitioning method was used to decompose the variance of phosphorus(total phosphorus,available phosphorus and available phosphorus)at 20 × 20 m scale into micro-terrain,plant community structure and spatial factor.The results of this study are as follows:(1)Spatial autocorrelation analysis shows that under specific spatial particle size conditions:The strong spatial autocorrelation of soil total phosphorus showed strong spatial autocorrelation at 10-140 m in the spatial size of 10×10m.In the space of 20×20m,the spatial autocorrelation showed a significant spatial autocorrelation at 10-70 m and 150-200 m.In the space of 40×40m,the spatial autocorrelation showed a significant spatial autocorrelation at 10-40 m,70-110 m and 190-200 m.In the space of 50×50m,the spatial autocorrelation is positive in the distance of 10-30 m,60-90 m and 150-170m;In the analysis of available phosphorus space autocorrelation,a strong spatial autocorrelation was observed at a distance of 10-200 m at a spatial particle size of 10×10m.In the space of 20×20m,the spatial autocorrelation is shown in the range of 10-200 m.In the space of 40×40m,the spatial autocorrelation showed a strong spatial autocorrelation at a distance of 10-80 m.In the space size of 50×50m,the strong spatial autocorrelation is shown in the distance of 10-60 m.In the spatial correlation analysis of available phosphorus in the soil,the soil available phosphorus ratio showed a strong spatial autocorrelation at a distance of 10-200 m at a spatial grain size of 10×10m.And a strong spatial autocorrelation is shown at a distance of 10-140 m at a spatial particle size of 20×20m.The spatial autocorrelation was significant at the distance of 10-80 m at the spatial particle size of 40×40m.Under the spatial particle size of 50×50m,the spatial autocorrelation is significant at the distance of 10-50 m.(2)Ordinary Kriging interpolation obtained spatial pattern distribution map,through the soil phosphorus spatial pattern distribution we can find: The overall distribution of soil total phosphorus,available phosphorus and available phosphorus was continuously distributed in the north-south direction,and the distribution of total phosphorus,available phosphorus and available phosphorus in the soil in the western,middle and eastern areas of the plot distribution area was concentrated,Between the eastern and central regions,the distribution of soil phosphorus between the central and western regions is less.The ratio of total phosphorus,available phosphorus and available phosphorus in soil was heterogeneous at a specific spatial grain size,The distribution of total phosphorus,available phosphorus and available phosphorus in soil was also different under the change of spatial grain size,but the overall trend was very similar.Compared with the distribution pattern of soil available phosphorus and available phosphorus,the distribution of total phosphorus in soil was distributed evenly.Compared with the soil total phosphorus,the spatial distribution pattern of available phosphorus was changed,and the spatial distribution pattern of available phosphorus was similar.(3)In the analysis of the influencing factors of the spatial distribution of soil phosphorus,the variance of the variance of the spatial variables was 58% of the total phosphorus,45.9% of the available phosphorus and 38.2% of the available phosphorus,indicating that both the total phosphorus,available phosphorus and available phosphorus The proportions showed a strong spatial heterogeneity;Topographic factors can account for 45.4% of the total phosphorus variance,33.3% of the available phosphorus variance,and 28.0% of the available phosphorus ratio deteriorated.The effect of topographic factors on total phosphorus is greater than that of available phosphorus.The plant community can explain 70% of the total phosphorus variance,52.2% of the available phosphorus variance,and 42.4% of the available phosphorus ratio,which is larger than that of the spatial factor and the terrain factor,indicating that the plant community is more closely related to the spatial distribution of phosphorus.In the analysis of variance of total phosphorus,21.6% of the total phosphorus variance was not explained.In the analysis of variance of available phosphorus,the total variance of available phosphorus was not explained.In the analysis of variance of available phosphorus,36.7% The variance is not explained.The variability decomposition indicated that plant community,spatial factor and ground factor had a great effect on soil phosphorus nutrient distribution.In addition to the factors affected by this study there are other factors,then what factors affect the distribution of the number of explanations,worthy of future discussion and analysis.