中国红树林天然分布北缘区不同起源秋茄热值特征研究

Characteristics of caloric values of Kandelia obovata among different origins in north marginal region of natural mangrove,eastern China

在测定红树林天然分布北缘区不同起源秋茄各器官干质量热值(GCV)的基础上,分析了不同起源秋茄红树林热值器官差异和滩位差异、秋茄天然林热值的径级变化和纬度变化。结果表明:秋茄天然林各器官热值均高于人工林,且各器官能量分配趋于均等,不同起源各器官热值顺序呈现出高度一致性,高低排序依次为叶、花、枝、树墩、干、粗根、细根、中根。秋茄热值随滩位向外延伸呈现上升趋势,天然林热值对滩位的响应比人工林更为敏感。从径级差异看,大致为径级越大,热值越高,径级Ⅳ热值>径级Ⅲ>径级Ⅰ>径级Ⅱ,另外径级变化对秋茄不同器官的影响程度不一。与其他纬度相比,红树林天然分布北缘区秋茄热值较其他纬度秋茄热值低,并且各器官间热值差异不显著。

Based on determining the gross caloric values（GCV） of Kandelia obovata from different origins in north marginal region of natural mangrove wetlands, eastern China, the paper makes an analysis of the difference in caloric value among each organ and different intertidal positions of varied original K. obovata, and the changing law of caloric value with diameter class and latitude in natural forest. It came to conclusions that GCV among each organ of the K. obovata natural forests, trending to equal, was higher than that of plantation. High consistency in the order of caloric value of the various organs was emerged between natural and plantation K. obovata, which was leaf, flower, branch, stump, trunk, coarse root, fine root, medium root from the high to the low. Caloric value of K. obovata appeared upward trend with the extending outward of beach, and the trend of natural forests was more sensitive than that of plantations. In diameter class, the lager the diameter was, the higher the caloric value was（ diameter Ⅳ 〉 Ⅲ〉 Ⅰ〉 Ⅱ）. In addition, the change of diameter class made varying degrees of impact on each organ of K. obovata. Compared with latitudes in other region, the caloric value of natural K. obovata in north marginal region was lower, and also, the change of caloric value among various organs was not significant.