伊犁野果林浅层土壤养分生态化学计量特征及其影响因素

Ecological stoichiometry of surface soil nutrient and its influencing factors in the wild fruit forest in Yili region,Xinjiang,China

对伊犁河谷野果林20个群落60个样方土壤及环境因子调查取样,研究了野果林0~10和10~20 cm土层土壤有机碳(C)、全氮(N)、全磷(P)及全钾(K)的化学计量特征及其影响因素.结果表明:伊犁野果林0~10 cm土层土壤C、N、P、K含量分别为73.15、7.00、1.14和14.74 g·kg^(-1),C∶N、C∶P、C∶K、N∶P、N∶K、P∶K分别为10.37、62.73、5.05、6.05、0.48和0.08;除K和C∶N外,0~10 cm土层均显著高于10~20 cm土层.P、K、C∶N及P∶K具有较高的稳定性(CV=8%~24%),其他指标具中等变异性(CV=28%~46%).土壤养分含量及化学计量比在不同取样地点、不同群落类型及不同坡向间均有显著差异.除C、N之间为幂函数关系外,土壤养分含量及其与化学计量比之间均为二次函数关系,体现了土壤养分化学计量特征之间的非线性耦合特征.坡向、降水量及温度是野果林土壤化学计量特征的主要影响因子.

Soil samples and environmental factors in 60 plots of 20 communities in the wild fruit for- est in Yili valley were investigated, and then the stoichiometric characteristics of soil organic carbon （C）, total nitrogen （N）, total phosphorus （P） and total potassium （K） in 0-10 cm and 10-20 cm layers and their influencing factors were studied. The results showed that soil C, N, P and K contents in 0-10 cm layer were 73.15, 7.00, 1.14 and 14.74 g · kg-1 , respectively. Soil C ： N, C ： P, C：K, N：P, N：K and P：K were 10.37, 62.73, 5.05, 6.05, 0.48 and 0.08, respectively. Ex- cept for K and C ： N, the stoichiometric values in 0-10 cm layer were significantly higher than that in 10-20 cm layer. Soil P, K, C：N and P：K presented high stability （CV= 8%-24%）, while oth- ers showed moderate variability （CV= 28%-46%）. Soil nutrient contents and their stoichiometric ratios differed markedly in different sampling sites, communities and slope aspects. Except the pow- er relationship between C and N, all the soil nutrient contents and their stoichiometric ratios repre- sented quadratic relationships, indicating nonlinear coupling among soil stoichiometric traits. Slope aspect, precipitation and temperature were the main factors influencing soil stoichiometry in the wild fruit forest in Yili region.