黔中石漠化区不同海拔顶坛花椒人工林生态化学计量特征

了解黔中石漠化区不同海拔顶坛花椒(Zanthoxylum planispinum var.dintanensis)人工林的生态化学计量特征,有助于深入认识其养分循环规律和元素丰缺状况。对顶坛花椒人工林叶片、凋落物和土壤C、N、P、K含量进行了测定,分析了生态化学计量特征及之间的关系。结果表明:(1)顶坛花椒人工林叶片OC、TN、TP、TK分别为228.11—446.81、0.96—5.69、2.17—5.60、6.42—17.74 g/kg,凋落物OC、TN、TP、TK依次为239.19—415.25、1.70—4.62、1.83—2.63、1.80—4.26 g/kg,土壤OC、TN、TP、TK分别为29.69—53.17、2.99—6.41、0.18—1.52、15.01—21.14 g/kg,土壤养分呈现低N高P格局;(2)叶片、凋落物、土壤C、N、P、K生态化学计量随海拔的分异规律不完全一致,其变化特征能够表明C、N来源多样,P、K来源相对固定;(3)土壤养分含量与叶片养分含量、生态化学计量之间多表现出显著相关,表明叶片养分主要来自土壤;总体上,土壤养分含量及其生态化学计量与凋落物养分含量具有弱的相关性,与凋落物养分生态化学计量具有强的相关性,表明凋落物和土壤之间存在一定的养分转换强度但是并非完全继承。

Ecological stoichiometry of Zanthoxylum planispinum var. dintanensis plantation at different altitudes in rocky desertification area of central Guizhou

Understanding the ecological stoichiometry of Zanthoxylum planispinum var. dintanensis plantation at different altitudes in the rocky desertification area of central Guizhou is helpful to know the regularity of nutrient circulation and the status of element abundance and deficiency. In this study, the contents of C, N, P, and K in the leaves, litter and soil of the Zanthoxylum planispinum var. dintanensis plantation were determined. The ecological stoichiometry and the relationship between them were analyzed. The results showed that: (1) the organic carbon (OC), total nitrogen (TN), total phosphorus (TP), and total potassium (TK) of the leaves of Zanthoxylum planispinum var. dintanensis plantation were 228.11-446.81, 0.96-5.69, 2.17-5.60, 6.42-17.74 g/kg, respectively. The OC, TN, TP, and TK of litter were 239.19-415.25, 1.70-4.62, 1.83-2.63, 1.80-4.26 g/kg, respectively. The OC, TN, TP, and TK in the soil were 29.69-5.17, 2.99-6.41, 0.18-1.52, 15.01-2.14 g/kg, respectively. The soil nutrients showed the pattern of "low N and high P". (2) The differentiation of C, N, P, and K in leaves, litter, and soil was not exactly consistent with the difference of altitude. Its change characteristics showed that the sources of C and N were diverse, but the sources of P and K were relatively fixed. (3) There was a significant correlation between nutrient content and the ecological stoichiometry in soil and leaves, which indicated that the nutrients in the leaves were mainly from the soil. In general, soil nutrient content and its ecological stoichiometry had a weak correlation with litter nutrient content, but strongly correlated with litters nutrient ecological stoichiometry. It indicated that there was a certain nutrient conversion strength between litter and soil but not complete inheritance.