南川百合与泸定百合种群格局分形特征的分析

Studies on the fractal properties of the distribution patterns among populations of Lilium rosthornii and Lilium sargentiae

本文应用计盒维数和信息维数比较分析了南川百合与泸定百合种群的空间分布格局及其分形特征。研究显示，南川百合与泸定百合种群的计盒维数和信息维数均较小（〈1．5，远离2），说明其占据生态空间的能力和格局强度都不大，体现其在群落中的劣势伴生地位。在2006年，南川百合各种群的平均计盒维数（0．7232）比泸定百合（0．7734）小0．0502，而其平均信息维数（0．4179）却比泸定百合（0．2381）大0．1798，这些数据表明，南川百合种群占据生态空间的能力比泸定百合弱，但其种群格局强度要比泸定百合种群大得多。在高温干旱的2006年，这两种百合的计盒维数与2005年相比都有所减少，信息维数都有所增加，但南川百合种群计盒维数的减少比例（13．87％）大于泸定百合（8．97％），约为泸定百合的1．54倍，其信息维数的增加比例（6．830%）却小于泸定百合（33．02%），泸定百合种群信息维数的增加量是南川百合种群的4．98倍，这些数据表明，高温干旱天气对这两种百合的生长均有影响；泸定百合的抗热抗旱能力要高于南川百合，南川百合更易受高温干旱天气的伤害。由于人为干扰和气候等环境因子的变化，南川百合和泸定百合均出现濒危迹象，此外，因南川百合抗热抗旱性能不强、占据生态空间能力弱等，导致其更加处于濒危状态，应尽快加以保护。

The fractal properties and spatial patterns of Lilium rosthornii populations and Lilium sargentiae populations have been studied by box-counting dimension and information dimension. The results which the boxcounting dimensions and the information dimensions of Lilium rosthornii populations and Lilium sargentiae populations were low （〈1.5,far from 2= showed that the spatial occupation degrees and the degrees of pattern intensities of these populations were not high, and that these populations were in an accompaniment position in these communities. In the year 2006, these data which, compared with Lilium sargentiae populations, the mean boxcounting dimension of Lilium rosthornii populations decreased by 0.0502, and in the other hand ,the mean information dimension of Lilium rosthornii populations increased by 0.1798 suggested that, compared with Lilium sargentiae populations, the spatial occupation degrees of Lilium rosthornii populations were lower, and however, the scale variation degrees of pattern intensities of Lilium rosthornii populations were more high than that of Lilium sargentiae populations. In the year 2006 of broil and drought compared with the year 2005, the mean box-counting dimensions of Lilium rosthornii populations and Lilium sargentiae populations were lower than that in 2005, while the mean information dimensions of them were higher than that in 2005; and however, the decrease percent of the mean box-counting dimension of Lilium rosthornii populations （13.87%）, which was 1.54 times as high as that of Lilium sargentiae populations （8.97%）, was bigger than that of Lilium sargentiae populations, while the increment percent of mean information dimension of Lilium rosthornii populations （6.83%）was less than that of Lilium sargentiae populations（33.02%） which was 4.98 times as high as that of Lilium rosthornii populations. The data mentioned above indicated that the growth of Lilium rosthornii and Lilium sargentiae was influenced very much by the weather of high temperature and drought, and that hotness and drought resistance of Lilium sargentiae was more high than that of Lilium rosthornii, and then the growth of Lilium rosthornii damaged by high temperature and drought. To sum up, Lilium rosthornii and Lilium sargentiae all had a evidence of endangerment because of change of environmental factors such as human＇s disturbance and change of climate, and besides, Lilium rosthornii was resulted in a state of endangerment because of itself such as low hotness and drought resistance and low spatial occupation degrees, so they need be pretected as soon as possible.