ICP—AES在濒危植物长序榆营养生态学中的应用

设立九龙山自然保护区（JL1、JL2）和松阳（SY）3个代表性样地，采用电感耦合等离子体原子发射光谱法（ICP—AES），测定了长序榆根、茎、皮和叶内的金属元素含量，并与土壤中对应的金属元素进行了相关性研究。结果表明，长序榆不同器官内的金属元素含量存在一定的差异，各元素含量在不同器官中的变化趋势和变异程度呈现不一致现象。大部分元素的含量虽然在种群间存在一定的差异，但差异没有达到显著水平；Mn、Ni、Ba3种元素的含量在种群之间存在显著差异。Mg、Mn、Ba、Ni、T15种元素的含量相对于植物体内其他元素与土壤各元素间相关性显著，Ca和Th均有很大的富集系数，表明长序榆植株内金属元素的分布和土壤元素存在相关性，且土壤中一些能被长序榆高度富集的微量元素的作用不能被忽视，需更加深入地研究。同时也表明，ICP—AES法在濒危植物金属元素含量与土壤的相关性研究方面具有广泛的应用前景。实验基于营养条件对物种濒危机制和保育策略进行的研究，将为濒危植物的保护开辟一条新的途径。

Application of ICP-AES in nutritional ecology of endangered plants Ulmus elongata

Ulmus elongata, an endemic species in China, has being one of the grade Ⅱ national key conservation rare and endangered plants. Based on the investigation, JL1, JL2 and SY three sampling plots were established. To well understand the element distribution of Ulmus elongata and its relationship with soil metal elements in those three populations, fourteen metal elements of root, stem, skin and leaf of Ulmus elongata sample were measured by ICP-AES. The results showed that： the content of elements among different organs were obvious different and its change tendency and variation degree were disaccord. Element contents among different populations were different. There were significant differences of the contents of Mn, Ni and Ba among different populations, but the differences of the most elements were not significant （ P 〉 0.05 ）. The correlation between plant metal elements Mg, Mn, Ba, Ni, Tl and soil metal elements was significant. The enrichment coefficients of metal element such as Ca and Th were much larger than the others, which indicated that absorption of Ca and Th by Ulmus elongata was of a certain peculiarity. There was a correlation between plant metal elements of Ulmus elongata and soil metal element. The effect of microelement should not be ignored in the growth and development process of Ulmus elongata, which was worthy of a thoroughly survey and study. Also, the results showed that ICP-AES could be used widely for analysis of the correlation between elements of endangered plants and soil physical and chemical properties in the future, and indicated that the new method would have practicability and reliability to a certain degree. Based on the nutrient conditions, the feasibility advices for the studies on the endangered mechanism and conservation strategy of rare plants were given. It would lay a foundation for further study on the conservation and breeding of endangered species and would have a broad prospect of applications.