黑石顶自然保护区常绿阔叶林优势植物地上部分的热值

对黑石顶自然保护区南亚热带低山常绿阔叶林地上部分各层次一些优势种和常见种的干重热值和去灰分热值的测定表明：植物的干重热值受灰分含量影响较大，植物去灰分热值随种类、器官而异，乔木层8种植物地上部分各器官平均去灰分热值在19．261-20．672kJg-1之间，各植物种的平均去灰分热值变化顺序如下：光叶红豆＞显脉新木姜＞福建青冈＞短花序楠＞生虫树＞小叶胭脂＞硬叶稠＞粘木。乔木层各器官的平均去灰分热值是：叶21．417kJg-1，幼枝19．929kJg-1，干树皮19．961kJg-1，干材18．664kJg-1。地上部分各层次相同器官平均去灰分热值有下列变化趋势：乔木层＞灌木层＞草本层，这一关系在植物叶的去灰分热值中表现尤为明显．

CALORIC VALUES OF ABOVEGROUND ORGANS IN EVERGREEN BROAD-LEAVED FOREST IN HEISHIDING NATURE RESERVE

The study of caloric values of different aboveground organs of some dominant and common species in south subtropical evergreen broad-leaved forest in Heishiding Nature Reserve, Guangdong Province, showed that the dry weight caloric values were affected obviously by the ash contents of plant species and of different organs of plant,and the ash-free caloric values varied with different species and organs. Mean ash-free caloric values for different organs of the same species among 8 species in the tree layer ranged from 19.261 to 20.672 kJ g-1, the ranking of Which in species being Ormosia glaberrima > Neolitsea phanerophlebia > Quercus chungii > Machilus breviflora > Cryptocarya concinna >Artocarpus styracifolius>Lithocarpus lohangwa >Ixonathes chinensis. Mean ash-free caloric values of the same organ for 8 species in the tree layer were 21.417 kJ g-1 for leaves, 19.929 kJ g-1 for twigs, 19.961 kJ g-1 for trunk barks, and 18.664 kJ g-1 for trunks.Ash-free caloric values of the same organ in different abovearound lavers tended to be in the following sequence; tree layer>shrub layer>herbaceous layer, which was shown markedly in ash-free caloric values in leaves.