基于大尺度条件探讨若干因素对植物热值的影响

热值作为植物的重要属性，具有一定的稳定性，是衡量植物第一性生产力、植物营养价值的重要参考指标，也是生态系统研究过程的重要参数之一。然而在热值的研究过程中，人们往往针对某种植物，或者某地区的某些植物来展开研究，很少在大尺度上对植物热值进行系统的研究。本研究搜集1989―2010年维普《中文期刊数据库》(http://www.cqvip.com)中公开发表的相关研究论文，对39个样地的547种植物的热值进行归类总结，在大尺度上探讨植物器官、科、生活型及经纬度对热值的影响。结果表明，不同生活型植物热值的顺序为乔木＞灌木＞草本，并且这种变化趋势不因植物种类和植物分布地区的变化而变化；草本与灌木植物叶片的热值最高、根系最低，而乔木则以枝条最高、根系最低；以草本和灌木植物为主的科，其热值要低于以乔木为主要组成的科，本研究所涉及的各科植物以藜科植物热值最低，杜鹃花科最高；植物的热值随着纬度的增加而升高。

Effects of several factors on plant calorific value based on large-scale conditions

Calorific value is one of the most important plant properties and is stabe normally.It is an important index on evaluating the plant primary productivity and plant nutrition,and also plays an important role in the process of ecology.In the researches of the plant calorific value,people paid much attention on just single plant species or some plant species grown in particular areas,but few people did some researches on large-scales conditions.We collected the published papers about the plant calorific value in PSTP(http: //www.cqvip.com) from 1989 to 2010,classified and summarized the calorific values of 547 plants in 39 plots,which attempted to discuss the effects of plant organ,family,life form,longitude and latitude on plant calorific values based on the large-scale conditions.The results showed that the order of calorific value of plants was Arbor>shrub>herbaceous,which did not show a variation tendency with the changes of the plant species and distribution.The calorific values of blades of herbaceous and shrubs were the highest,while those of roots were the lowest.For arbor,the calorific value of shoots was the highest,that of roots was also the lowest.The calorific value of a family which had mainly herbaceous and shrubs was lower than that of the family with most of arbors.The study also indicated that Chenopodiaceae plants had the lowest calorific value;Ericaceae had the highest value.The calorific value of plants also increased with increasing latitude.