雪岭云杉林土壤-叶片碳、氮化学计量特征对NDVI及环境因子的响应

Responses of Stoichiometric Characteristics of Soil and Leaf Carbon and Nitrogen in Picea schrenkiana Forests to NDVI and Environmental Factors

为了阐明不同生长环境下,土壤对植物营养元素的供应以及植物的生长状况,我们以天山雪岭云杉林为研究对象,运用多元回归分析探究了不同海拔高度上土壤和叶片碳(C),氮(N)化学计量特征对环境因子的响应,以及土壤C,N含量对叶片C,N含量的影响。结果表明:土壤C含量的变化范围是15.86~84.14 g/kg,平均值为43.18 g/kg;土壤N含量的变化范围是0.13~0.54 g/kg,平均值为0.28 g/kg;土壤C∶N的变化范围是70.86~343.90,平均值为164.27;叶片C,N含量的变化范围是321.90~598.96,0.69~17.07 g/kg,平均值分别为471.98,6.71 g/kg;叶片C∶N的变化范围是28.49~217.10,平均值为83.22。叶片C含量、土壤N含量对海拔的响应显著,除此以外,其他均与海拔之间无显著的响应。多元回归分析表明年均温度(MAT)和年降水量(MAP)对土壤C,N影响显著,但主要贡献来自于MAT,坡向和NDVI对土壤C,N的影响均显著,土壤C∶N对MAT、MAP、坡向、NDVI的响应均不明显;叶片C,N与MAT,MAP之间的相关性不显著,NDVI对叶片C有显著的影响,土壤C,N对叶片C,N的影响显著,叶片C,N与环境因子及土壤C,N化学计量特征均无显著相关性。

In order to clarify the supply of nutrient elements and the growth status of plants in different growing environments,we studied the response of stoichiometric characteristics of soil and leaf Carbon(C),nitrogen(N)to environmental factors at different altitudes,and the effect of contents of soil C,N on contents of leaf C and N by using multiple regression analysis.The results showed that the variation range of soil C were 15.86~84.14 g/kg and the average was 43.18 g/kg,and the variation range of soil N were 0.13~0.54 g/kg,and the average was 0.28 g/kg,the variation range of soil C∶N was 70.86~343.90 and the average value was 83.22;and the variation ranges of leaf C,N were 321.90~598.96 g/kg and 0.69~17.07 g/kg,respectively,and the average values were 471.98,6.71 g/kg,respectively,the variation range of leaf C∶N were 28.49~217.10,and the average was 83.22;there were no significant differences in stoichiometric characteristics of C and N of soil and leaf with elevation except for soil N and leaf C;the multiple regression showed that annual mean temperature(MAT)and annual precipitation(MAP)had significant effects on soil C and N,but the main contribution came from MAT,and the effects of aspect and NDVI on soil C and N were significant,but the response of soil C∶N to MAT,MAP aspect and NDVI was not insignificant,the correlation between leaf C,N and MAT,MAP was no significant,but there was significant correlation between leaf C and NDVI;There was significant response of leaf C,N to soil C,N,however,there was no significant correlation between leaf C∶N and environmental factors and soil C and N stoichiometry characteristics.