Study On The Characteristic Relationship Between Soil And Leaf Nutrient Elements Of Carya Dabieshanensis

Carya dabieshanensis is a kind of dried fruit and woody oil tree with economic value.Due to its high nutritional value and good cultivation efficiency,it has received the attention of forest farmers.In order to study the characteristics of nutrient elements in soil and leaf,provide a reference for the management of Carya dabieshanensis,the characteristics between soil and leaf nutrient elements and there relations hip were analyzed.Based on the investigation and according to the distribution characteristics of Carya dabieshanensis in the southern anhui mountains,203 soil samples and 198 leaves from 0?20cm were collected from 21 points to determine the nutrient content.The results are as follows:(1)The soil nutrient content in the Carya dabieshanensis was determined.The average pH value is 5.22,the range of variation is 4.18-7.11;The average value of soil organic matter is 50.90g/kg,the range of variation is 11.65?131.38g/kg;The average value of available nitrogen is 171.46mg/kg and the range of variation is 44.78?552.95mg/kg.The average content of soil phosphorus was 990.89 mg/kg,and the range of variation was 154.38?2462.08 mg/kg.The average available phosphorus content was 20.43 mg/kg,the range of variation was 1.98-8.70 mg/kg.The average value of soil potassium content was 8266.50mg/kg and the range of variation was 4354.22-15634.86mg/kg.The average value of available potassium was 70.03 mg/kg,and the range of variation was 20.54?126.52 mg/kg.The average values of calcium,magnesium,manganese,zinc,copper,nickel,lead,chromium and cadmium wer e:708.21mg/kg,2530.88mg/kg,744.38mg/kg,155.40mg/kg,31.57mg./kg,3.10 mg/kg,2.85 mg/kg,5.81 mg/kg,and 0.036 mg/kg,respectively.(2)The content of nutrient elements in Carya dabieshanensis leaves was deter mined.The average nitrogen,phosphorus,potassium,ecalcium and calcium content were 27934.22mg/kg,429.55mg/kg,7715.82mg/kg and 12023.66mg/kg respectively.The mean values of magnesium,manganese,zinc,copper and nickel contents were 3183.15mg/kg,715.13mg/kg,81.27mg/kg,14.24mg/kg and 5.64mg/kg,respectively.(3)The relationship between soil and leaf nutrient elements of Carya dabieshan ensis was analyzed.The results showed that the leaf total phosphorus is linear with soil total phosphorus,leaf available nickel and soil nickel.The equations are:y=0.089x+334.494(P<0.01)and y=0.394x+4.309(P<0.01),there is no significant linear relationship between other elements.(4)The relationship between the soil and leaf nutrient elements of Carya dabieshanensis with altitude was analyzed.The contents of leaf available potassium,soil nickel and leaf available nickel tended to increase with altitude.While the soil phos phorus,leaf available calcium,soil magnesium,leaf available magnesium and soil zinc content showed decreased.The content of soil total potassium,leaf phosphorus,soil calcium,soil manganese,soil copper and leaf available copper decreased first and then increased with altitude,the leaf effective manganese and available zinc content of leaves increased first and then decreased.(5)The fitting equation between soil organic carbon and pH value,available nitrogen,available potassium and calcium was established.There is a significant corre lation between soil organic carbon and soil pH value,and the power coefficient is exponential.The correlation coefficient is R2=0.0 1 59,its expression fitting equations for y=105.3x70.834(P<0.01).There is a significant significant negative correlation between soil organic carbon and soil Ca.The equation of the expression was y=0.00783+35.897x(P<0.01),correlation factor was 0.086.Soil organic carbon was significantly linearly correlated with available nitrogen and available potassium,and the R2 values were 0.482 and 0.219,respectively.The equation expressions were y=0.120x+8.866(P<0.01),y=0.239x+13.317(P<0.01).(6)The correlation characteristics between soil organic carbon and pH value,available nitrogen,available potassium and calcium were analyzed.According to the st ructural equation,the correlation diagrams of soil pH,available nitrogen,available p otassium,calcium and organic carbon were established.Soil pH value,available nitrogen,available potassium and calcium had a direct impacts on soil organic carbon.The path coefficients were-0.312(P<0.01),0.641(P<0.01),0.548(P<0.01),and-0.457(P<0.01),respectively.The soil pH value can affect soil organic carbon by affecting soil available nitrogen and available potassium,and the influence coefficients are 0.224(P<0.01)and 0.301,respectively.pH value,available nitrogen,available po tassium and calcium have direct effects on organic carbon,and pH also affects organic carbon indirectly through available nitrogen and available potassium.