We compared and analyzed the primary anatomical structures for stem of Carum carvi on five different alti-tudes by paraffin section methods,and observed the structure with unidimensional and two-dimensional (area)index properties,in order to find out the change rule of structures for stem of C .carvi with the rising of elevation,which could provide basic information for the development and utilization of C .carvi .The test showed that stem primary structure consisted of cortex and vascular cylinder.With the altitude increasing,the thickness of epidermis and pith, the width of pith ray and the area of aerenchyma gradually increased,but the ratio of vascular tissue to fundamental tissue gradually reduced;the number of layers and thickness of cortex,the number and thickness of vascular bundle gradually decreased,however,the development degree of vascular bundle and the diameter of duct gradually increased. The thickening of epidermis could reduce the losing their body heat and decrease the damage from strong ultraviolet rays;The increasing of ratio of fundamental tissue was conducive to store more physiological regulatory substances, increase of cold resistance abilities in the plant;The development of aerenchyma could reduce the diffusional resist-ance of the alr inside the plant,channel being formed along aerial parts to underground part,and also could increase the plant's buoyancy,reduce the proportion of plants.The varying of anatomical structures for stem of C .cavri during different elevation reflected plant adaptations for environment.But in this experiment,some special phenomenon was observed,the number of layers and thickness of cortex in C .carvi stem,this phenomenon was reported in the aerial stem structures of Kobresia pygmaea and its mechanical tissue of aerial part had a decline meanwhile underground part had a rise.Whether this kind of phenomenon exists or not,we must further carry on study about anatomical structures for root of C .carvi .In this study,we also found that the number and thickness of vascular bundle gradual-ly decreased,however the development degree of vascular bundle and the diameter of duct gradually increased with the increasing of the altitude.The possible reason was that its low temperature and short frostless period were under the high altitude conditions,the plant developed more completely under the high altitude areas than the low altitude areas in same growth period.It also reflected plant adaptations for environment.And the problem about development degree of the same plant in different altitudes still need further research.%采用石蜡切片法，分别对5种不同海拔高度藏茴香茎初生解剖结构进行比较研究，并用一维和二维(面积)的度量指标进行观测，以期探索随海拔升高，藏茴香茎结构的变化规律，从而探讨藏茴香对高寒气候的适应性，为藏茴香这一食用、药用植物资源开发利用提供基础资料。结果表明：藏茴香茎的初生结构由表皮、皮层、维管柱构成，随着海拔升高，藏茴香茎的表皮厚度、髓厚度、髓射线宽度以及通气组织的面积逐渐增加，而维管组织与基本组织的比值不断缩小，皮层的细胞层数、厚度逐渐下降；维管束的数量、厚度不断降低，但维管束的发育程度和导管的直径有逐渐增加的趋势。藏茴香茎表皮的不断增厚，可以减少植物体内热量的散失，并有效地降低强紫外线对植物造成的伤害。基本组织比例的增加，有利于贮藏更多的生理调节性物质，增加植物的抗寒能力；通气组织逐渐发达，可极大地降低空气在植物体内的扩散阻力，形成氧气由地上部运输到地下部的通道，还可增加植物体的浮力，减轻了植物体比重，对植物体起到了良好的支撑作用。藏茴香茎解剖结构随海拔的变化，体现了植物对环境的适应性。研究中发现的随着海拔升高，茎皮层的细胞层数和厚度以及茎中维管束的数量和厚度均下降，但维管束的发育程度和导管直径增加的现象，还有待于进一步研究。
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