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

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.

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

Soil samples and environmental factors in 60 plots of 20 communities in the wild fruit forest 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. Except 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 others 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 power relationship between C and N, all the soil nutrient contents and their stoichiometric ratios represented 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.