四种园林植物的热值与养分特征

测定了蔷薇科植物美人梅、樱花和木兰科植物白玉兰、广玉兰不同组分的热值、养分和灰分含量, 探讨4种植物不同发育阶段根系、枝干和叶等器官的热值分配特征及其影响因子. 结果表明: 4种植物不同组分干质量热值和去灰分热值在17.02～21.93 kJ·g^-1和18.42～22.57 kJ·g^-1之间; 叶片和细根具有较高的干质量热值和去灰分热值, 去灰分热值随着根系和茎干（枝）的发育呈减小趋势. 美人梅和樱花的干质量热值和去灰分热值总体上高于白玉兰和广玉兰. 细根干质量热值和去灰分热值与其养分和灰分含量呈极显著相关(P<0.01). 随着根系的发育, 干质量热值和去灰分热值与有机碳含量的相关性逐渐降低, 不同器官干质量热值与全氮含量相关性最强.

Characteristics of caloric value and nutrient content of four garden tree species.

In this study, the caloric value, nutrient content, and ash content in the stem, leaf, and root of four garden tree species Prunus mume Meiren, P. serrulata, Magnolia denudata and M. grandiflora were determined to explore the distribution characteristics of caloric value in different tree organs at different development stages, and related affecting factors. The results showed that the gross caloric value (GCV) and ash free caloric value (AFCV) in different organs of the tree species ranged from 17.02 to 21.93 kJ g(-1) and from 18.42 to 22.57 kJ g(-1), respectively. Leaf and fine root had relatively higher GCV and AFCV than stem, and AFCV had a decreasing trend with the development of stem and root. P. mume Meiren and P. serrulata had higher GCV and AFCV than M. grandiflora and M. denudate. Both GCV and AFCV of fine root were significantly correlated with its nutrient and ash contents (P <0.01). With the development of root, the correlations of GCV and AFCV with organic carbon content declined gradually, while the GCV of different organs had the strongest correlation with total nitrogen content.